Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: Bald_Eagle1 on August 06, 2011, 03:44:56 AM

Title: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 03:44:56 AM
Hi,

I live around 0.5 mile from the FTTC cabinet to which I am connected (by road, not in a straight line).

I had FTTC installed in June with an pre-install estimated line speed of only 15 Mbps.
Due to the distance from the exchange, I was only ever able to download at 1 Mbps via ADSL. Hence the switch to FTTC.

However, I enjoyed a FTTC profile of around 35 Mbps, with download speeds consistently at 32-33 Mbps for the first couple of weeks.

I have had a few problems since then, such as no phone or broadband service at all for a 4 day spell.

The loss of service was "fixed" by BT (externally) at the end of July & my profile was remotely reset & the BT modem was replaced 4th August due to an "overheating" issue.

The profile was reset at 25 Mbps & downloads of 22-23 Mbps were achieved for a just a few hours.
The engineer asked BT why my profile was not reset to the original 35 Mbps.

BT's response was that it could never have been that high, & I could never have achieved 32-33 Mbps download speeds due to the distance from the cabinet.
This was despite the engineer quoting actual download speeds from my printouts over the phone to BT.

I suffered a few modem disconnections during Friday 5th August, with the phone line also sounding crackly.
The broadband connection appears stable & the phone is quiet again now though.

Currently, my download speeds are only around 14 Mbps, with a profile of 15 Mbps.

My questions are:-

1) Can anyone give me a realistic estimate of the stable profile / download speeds that I should be able to achieve with a copper line length of around 0.5 mile to the cabinet?

2) As both BT & my ISP deny any resposibility for the current drastic loss of speed of almost 20 Mbps, can anyone give me any advice on what I could say to make them at least investigate again?

3) Are my expectations too high? i.e. do all FTTC installations start off at high speeds, with some connections stabilising at a much lower speed?

4) Is it likeley that, with a bit of patience, my profile & download speeds will increase back to 30 Mbps or so?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 06, 2011, 09:42:53 AM
Hi Paul,

Our worthy and frequent BT contributor Razpag will be best to answer detailed questions as he has actually installed many services already.

However it seems apparent that the seemingly eternal tensions between BT Openreach, BT Wholesale and your ISP are continuing apace. As you've had a much higher speed, unless you have a restricted package with stated much lower speeds, I believe you should demand of your ISP that they restore your original conditions as the service is not now fit for purpose.
YOU will have to pester your ISP as nobody else will.
As you'll see elsewhere here patience is in invaluable virtue - nil desperandum !!!!

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 06, 2011, 10:06:03 AM
Ha ha ha, thanks for the glowing introduction Walter  ;D

Hmmm, where to start ?? Well, in laymans terms or at base level if you prefer, if you've 'synched' at 35 Meg previously, then there is no reason at all why you shouldn't achieve that figure again !!

When I read your thread title and opening paragraph, I have to adnit I was also thinking roughly 30+ Meg connection speeds. An exact figure cannot be given as it depends on the make-up (and condition) of the D-side cable from the Cabinet to your premises.

You will see I make a point of mentioning 'the condition' of the D-side network, as it does appear you may have had a 'HR' type fault causing a noisy line, which in turn will drop your connection speeds quite dramatically. There's a lot of folk on here who can elaborate on HR faults if needed.

In answer to your Q's though .........

1) It can only ever be an estimate without being 'on-site', but anything over 30Meg should be easily achievable unless your D-side network is made up of wet string. (Disclaimer- this is your quoted figure of 0.5 Miles, it may actually be more or less).

2) I would ask your ISP to look over the RRT (Repair Reactive Tool) which should show all figures related to your circuit. This will back up your claims of a 35 Meg connection.

3) Increments (up and down) of speed are expected over the initial stabilisation process. However, nowhere near 20 Meg !!!!!

4) If a fault has been repaired (as in the HR fault), then full recovery of the Throughput Speeds (surfing speed) will take place over a period of time, usually between 3-10 days. But, I generally find the 'Synch speed' recovers instantly ?! In other words, if the fault is fixed you synch should adjust back to MSR (Maximum Stable Rate) instantly. The only reason this may not happen is if a 'hard cap' has been put in place by your ISP.

Hope this helps bud ?? ;D
 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 10:15:40 AM
Hi,

My ISP is Plusnet (owned by BT, but that never seems to add any weight in resolving line problems).

Unlike many ISPs, Plusnet are usually pretty good at listening to & dealing with "technical" problems. However, they say that as my line faults were "fixed", & I was achieving download speeds higher than the estimated 15 Mbps, there is nothing they can do to report a fault to BT:-

"Thank you for getting back to us. I am sorry to hear the speed is not at the previous your had it but your actual estimated line speed is still lower than what you are currently achieving. Due to this we cannot push this any further as the line is performing over an acceptable rate for the length of your line.

I have included the estimate below for you :

Our test also indicates that your line currently supports a fibre technology with an estimated WBC FTTC Broadband where consumers have received downstream line speed of 14.6Mbps.

Your line speed will fluctuate above and below this.  I do apologise for any inconvenience caused."


From BT's speed tester this morning:-
 
"Download speed achieved during the test was - 13704 Kbps
 For your connection, the acceptable range of speeds is 10535-15050 Kbps .
 Additional Information:
 IP Profile for your line is -15050 Kbps"

also:-

"We were unable to identify any performance problem with your service at this time."


Regards,

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 03:13:11 PM
Hi razpag,

Thanks for your response.

Yes, I have previously synced at around 35 Mbps - from BT's speed tester:-

 "Download speed achieved during the test was - 32359 Kbps
 For your connection, the acceptable range of speeds is 22767-32525 Kbps .
 Additional Information:
 IP Profile for your line is -32525 Kbps"

I take it (maybe incorrectly) that an IP profile of 32525 Kbps comes from a sync speed of around 35000 Kbps (35 Mbps).
That was the sync speed the original installation engineer told me I had achieved.

Even if my understanding is incorrect, actual download speeds were between 32 & 33 Mbps.

Very briefly, what is a HR type fault?

1) By road it is around 0.5 mile. In a straight line it is much less (not relevant though). The line is at the very least 10 years old, probably quite a bit older. It does zig-zag quite a bit too.
Just for curiosity, if the line was indeed much longer than 0.5 mile (say a full mile due to the zig-zagging), could I have ever synced at 35 Mbps? I have seen a few charts, but they do appear to contradict each other somewhat.

2) A short while ago this morning, my ISP confirmed they will be taking no further action as my service is being delivered within specification. I wrote back with a long (very long) response, particularly mentioning the crackly phone line.
As my phone provision is also via my ISP as a phone / broadband bundle, I am not allowed to contact BT regarding line "faults".

3) I expected some speed fluctuations (contention, traffic management, condition of mainly overhead line being affected by temperature/rain etc.).

4) There has been no mention of a hard cap by my ISP.
Two days after the fault "repair", according to a report from my ISP, it was confirmed that Interleaving was automatically set at "HIGH" for the downstream & at "ON" for the upstream.
The report also confirmed Downstream Speed 12.857 Mbps, Upstream Speed 0.79800004 Mbps.
Since then, the BT modem has been replaced & my profile reset (only at 24 Mbps though).
Would Interleaving affect sync speeds, or just throughput speeds? The engineer who replaced the modem & organised the profile reset had never heard of Interleaving so couldn't comment.
He also said he couldn't check anything in the cabinet as he wasn't allowed to access cabinets.
Do BT engineers have differing access levels? The original installation engineer did struggle a bit to get me set up, flitting between my home & the cabinet, saying he eventually found a dodgy connection in the cabinet.

Would the profile reset have turned off any interleaving anyway?


From what I have read up on so far (elsewhere), it appears that profile speeds via FTTC are very quickly lowered following "faults", but can take much more than 10 days to recover (sometimes being stuck forever at the lower rates).
Unlike ADSL, ISPs (& remotely located BT staff???) apparently now have no control whatsoever over profile speeds / interleaving etc., having to rely entirely on the DLM in the cabinet itself?

So many questions from a newbie!!!
Don't worry, once I'm an "expert" I will give back my own "two penn'orth".

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 06, 2011, 03:25:01 PM
Paul,

If you haven't already done so, you need to request that your PlusNet Help Assistant request is escalated to bob Pullen, their chief trainer, stating again that your line has performed significantly faster and that it appears to be exhibiting a High Resistance type of fault.

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 03:39:09 PM
Thanks Waltergmw,

Are you a Plusnetian too?

I have dealt with Bob Pullen in the past when, very rarely, matters appear to get stuck.
Not much can really go wrong with an ADSL provision of 1 Mbps, that actually gives you 1 Mbps.

This whole FTTC thing is a whole new ball game though.

There are others too, such as Adam, Jojo, Matt that I could ask via Community forums.

I didn't really want to go too public & come across as a right old whinger (not yet anyway).

Thanks also for clarifying what a HR fault is.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 06, 2011, 03:42:58 PM
I have read this thread with interest and there is one thing that stands out.
Quote
However, they say that as my line faults were "fixed", & I was achieving download speeds higher than the estimated 15 Mbps, there is nothing they can do to report a fault to BT:-
That absolutely stinks of the old upto 8megs. I know we are talking higher figures with the FTTC but the mention of achieving what they (Plusnet owned by BT) feel is an acceptable connection rate. I would say you are on an uphill struggle to improve things. It's like trying to run through treacle once things like that get mentioned.
If Walters suggestion works then it will be wonderful, however I doubt very much that you will get any favourable response as it will leave the door wide open for anyone in the same or similar situation contacting the person mentioned.
Good luck all the same.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 04:12:13 PM
Cheers silversurfer44,

I have been tempted to contact that person a few times already, but have intentionally held off until now as he does seem to pick up a lot of unnecessarily messy "issues".

I don't know how/why he does it for the money (whatever he gets - it won't be enough).

As FTTC is a relatively new(ish) technology, I have been giving people the benefit of doubt that we don't yet fully understand it.
By carefully (& repeatedly) explaining my own issues to them (backed up with hard facts), I hoped they would take my feedback as a learning curve for us all.

I am however now wondering whether or not I made the right decision in switching my BT phone line provision to an ISP provider (albeit BT owned) as reaction times to phone line "faults" appear to have slipped a little.

I have struggled up a few hills in my time & I ain't giving up on this one.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 06, 2011, 04:31:09 PM
Hi
As a matter of interest what is your current SNR margin? and what was it when you were synching at 30 +Mbits
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 04:41:02 PM
Hi jeffbb,

I have no idea.

The BT provided VDSL modem has no access for numpties like end-users.

The Netgear WNR1000 v 3 router that goes with it doesn't provide this information either (unless I just can't find it).

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 06, 2011, 06:50:21 PM
Hi Paul,

I help a lot of folks out in the sticks of the Surrey Hills so I have some experience of several ISPs.

It will be well worth finding out as much as we can of your perceived line length a) from here http://www.kitz.co.uk/adsl/adslchecker.php

and b) if you would kindly PM me with the phone number (not to be used or disclosed elsewhere) I may be able to obtain some other data.

I also fully support SS44's comments. This type of reply is IMHO quite unacceptable on an expensive FTTC service. It makes a total mockery of all the Ofcom calculations recently published. Nor does it help good engineers such as RP to get authorisation to investigate what might be a reasonably simple fault to investigate.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 07:03:51 PM
Hi waltergmw,

These are the results, but they are from the exchange for ADSL checking purposes.
Distance:- Direct:    4.28 km
  (appx)* By Road: 4.99 km

For FTTC, as I understand it, the relevant distance is from the end-user to the cabinet.

I know from the BT engineers which cabinet I am connected to, & by road it is around 0.5 mile.
The overhead line does also take a bit of a zig-zag route.

Paul.

P.S. PM sent.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 06, 2011, 07:45:27 PM
Hi again Paul,

You're absolutely correct re the distance you need. I suspect somebody in PlusNet has not yet woken up to the fact that it's PCP to home distance than now needs to be measured, but I for one don't have access to that information. (@ RP do you know the new FTTC to EU distances or can you only measure them with your JDSU or whatever?)
My check suggests you have a bRAS rate of 15050 Kbps, that you have a 21CN line from MROLD and that your line length as recorded by BT is a mere 5283m !!!!!!!!!!!!!
I also believe you are connected to PCP 51 and that all lines in that postcode are similarly connected. You might have an uplift of 18.21 times your exchange speed (Take that with a pinch of salt) and that your installation was supposed to be complete in phase 2 of BT's FTTC programme.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 08:00:32 PM
Hi Walter,

Yes, the BT engineers (various) have confirmed it is indeed PCP 51.

If needs be, I could PM you with my actual home location if it would help determine actual line length from the PCP.

That is exactly the same as reported in this morning's BT speedtest, with a 13704 Kbps achieved download speed.

What are/were the dated for BT's FTTC programme?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 06, 2011, 08:12:08 PM
Hi Paul,

I haven't the historical times but I think we may know someone who does ! (RP ?)

The only way I know is either a pair of walking boots with a tape measure and then a map.

Or in our case, SCC have a fantastic interactive mapping system which provides such distances so you might just try your .gov website.

For those in Surrey ours is:-

http://www.surreycc.gov.uk/sccwebsite/sccwspages.nsf/LookupWebPagesByTITLE_RTF/Surrey+Interactive+Map#

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 06, 2011, 09:39:40 PM
Hi walter,

We might just be getting somewhere now.

5283 m = 3.28270 miles, or 3 miles & 497.5 yards.

I have always reckoned that I live about 3 miles from Oldham town centre (by road).
The Oldham exchange is quite near the town centre.
Adding say 0.25 mile or so for any deviation of the cable route, the overall line length that you found is possibly quite close to reality.

So, if we could find out the line length that PCP 51 is from the exchange, we could work out a realistic line length from the cabinet to my home. This should then help us determine realistic FTTC profile/download speeds (assuming the line & any connections are in reasonable condition).
At least I would have a realistic line length that I could quote to Plusnet.

After BT reset my profile on Thursday at 24 Mbps, stating it was the maximum profile for my broadband, my IP profile from BT's speed tester was 23464 Kbps.

It may just be coincidence, but isn't this quite close to the "up to 24 Mbps" speeds for ADSL2+ available via the 21CN that BT state that I am connected to?

Is FTTC also delivered via 21CN?

Is it therefore feasible that BT actually reset my profile to the maximum value, but based on the wrong technology/information in their database, & therefore my current profile of only 15050 Kbps has been has been automatically reset due to the intermittent RH fault & distance from the cabinet against the wrong criteria?

If that is the case, maybe all it will now take to sort this out once & for all will be a simple phone call to my ISP?

It all sounds too simple, but sometimes simple explanations can be easily overlooked when dealing with technology.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 06, 2011, 11:38:38 PM
Hi Paul,

Do you know a friendly neighbour or two directly beside the PCP who would be prepared to lend his / their number(s)?

The reason I suggest at least two is that the line distance recorded sometimes seem to vary with the wind direction. (Joke!)

I would certainly mention the 21CN readings to your ISP. As 21CN is a marketing term rather than a full technical description I have no idea if it is applied to a FTTC service but perhaps RP might comment tomorrow.

In our area we have noticed that the 21CN migration can be observed (without FTTC being available) by the DSLAM now being identified as Infineon rather than a number of other makers and the BT speed test is expanded to give both download and upload speeds etc. We also observe that the bRAS / IP Profile changes immediately a significant sync speed has occurred. I see that FTTC users are instructed to use the same test but I've not seen the results of a FTTC speed test.

Another item that is unclear is the use of the Circuit Identifier. Given that your internet traffic is now transported, along with all the others, in IP packets from the FTTC backwards it may mean very little except for the phone which is still connected directly to the exchange. Taking this one stage further it might be possible to have noise or other effects from the FTTC phone link cable plus the E side cable being reflected into the VDSL2 signal. I shudder to think of all the other crossed pairs / transposed wiring possibilities but if an engineer has been investigating your circuit, I assume he might have had to isolate your pair by disconnecting it, just as is done in a normal joint sleeve when fault finding. Do also remember that there are now two cabinets and two extra link cables to consider. Furthermore, even though this equipment is relatively young, there are presumably a totally different set of procedures in place to allow a different port on the FTTC DSLAM to be changed. To save messing about in the FTTC it is possible that engineers just make those adjustments using the two link cables in the PCP, assuming every new link double-pair is tested during FTTC commissioning. When a FTTC is being commissioned the link cables in the PCP are stripped back leaving each pair floating, but all the link pairs in the FTTC are all punched down into their respective IDC connector blocks (as I call them). As the PCP ends cannot be connected it might mean that each set of double-pairs cannot be tested ?  More comments if possible from RP please. (EDIT Extra lines added)

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 12:08:20 AM
Hi Walter,

No, I don't know anyone near the PCP & I don't think the residents would take very kindly to a total stranger turning up out of the blue & asking for their phone number.

This morning's BT speed test attached.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 07, 2011, 08:52:26 AM
Hi lads.

Your synch speed of 15Meg is the lowest the DLM is allowed to take you. When we have a FTTC Install, we test at the PCP first to make sure we're getting the right produst on the right port ..... IE- 40Meg DS and 10Meg US, or 40/2. These are the only 2 products currently available from my own observations. If all is well at the PCP, we then ring the EU to confirm they still want to go ahead with the installation, and if so, to inform them their services will be 'down' for 'x' ammount of time. Once the PCP work is done, we travel to the EU's and perform another speedcheck via our JDSU/EXFO testers. If the product is sub 15 Meg at the EU's, we then have to ring a particular helpdesk number to inform them, and I'm not sure what happens next ?? The reason I don't know is that I've never had this happen to me.

Going back to your query B.Eagle, if you have had 35 Meg before, you will definitely be able to get it again. You have historical data according to your posts, to back up your claims, and the ISP's RRT data should also uphold your claims.

I'm not sure from your postings whether you've had a fault, or if you have, whether it's been cured ?? If the ISP reset you to 24 Meg on Thursday, and you are now back at 15Meg, I would say that you may still have a fault present. Personally, I wouldn't get tied up in line lengths, split pair cabling, HR's etc etc .... if you have hard proof that you were connected at 35Meg, then this is the angle to hit them with. Let 'us' worry about the other stuff. 
I always state it's damned near impossible to 'remote fault' over the web. I would persist in your quest, because you are not receiving what you should if your previous connection was at 35Meg !!!!!!

It's a shame you're in Oldham, as I work very close to you, sometimes crossing into Oldham itself in busy periods. Unfortunately, it's not part of my patch whatsoever. Shame, as if you'd got a job raised I could have possibly got it 'pinned' to me. I find it slightly worrying that the other engineer didn't know what Interleaving is as well ??. Madness.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 02:02:29 PM
@ razpag,

The faults have been:-

1) Overheating modem, but might just have been a pre-cursor to a line fault

2) Massive drop in download speeds & for a while drop in upload speeds.

3) Complete loss of broadband & phone for 4 days (supposedly fixed)

4) Intermittent disconnections & crackly phone line since it was "fixed" therefore still a reportable fault?

5) Interleaving set at HIGH for downstream, but I'm not sure if that would affect my sync/profile speeds.

6) Modem replaced & profile reset, but was it actually set for the correct FTTC service, or incorrectly reset for ADSL2+?

I have lots of proof regarding previous download speeds.

The line length stuff was just my attempt to prove what theoretical speeds I shoud be able to sustain, & to possibly highlight that BT & Plusnet both (incorrectly?) think my line is too long to sustain anything higher than 15 Mbps.

I have attempted to escalate these issues to Bob Pullen at Plusnet.
If I ever receive another notice of an engineer's vist, I'll keep you posted, on the off-chance that you might just be able to intervene as you do seem to have a much better understanding of these issues than some of the previous engineers.

I accept it is nigh on impossible to diagnose faults over the web.
I certainly couldn't do it with my job (Building Surveying).
People still ask me to do it though e.g. "what's causing the rising damp in my house & how much will it cost to fix it?"
More often than not, it is just condensation, but I can't prove it one way or the other without a site visit & quite a bit of physical investigation.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 07, 2011, 03:53:21 PM
I really do sympathise with your predicament. Most, if not all, ISP's support services are a nightmare to deal with. I know this from the sometime tirade of abuse I receive, upon visiting the EU's premises.

Back to your problem though, and you have the answer right there in your own post .............

4) Intermittent disconnections & crackly phone line since it was "fixed" therefore still a reportable fault?

THAT is the reason your speed is right down to the bottom (15 Meg). We can carry on discussing the science behind AC Balance, Power Spectral Density and Longtitudinal pair Balance, or how to access DMT/BPT graphs and tweaking your SNR, but until you ring your SP (telephony provider) and tell them you have a noisy (crackly) line, we may as well talk about the price of Cockles on Morecambe promenade.

Ring them now. Get a 'Network Fault' (not a Broadband fault) raised for a 'LTOK noisy line'.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 04:52:20 PM
Back to your problem though, and you have the answer right there in your own post .............

4) Intermittent disconnections & crackly phone line since it was "fixed" therefore still a reportable fault?

Ring them now. Get a 'Network Fault' (not a Broadband fault) raised for a 'LTOK noisy line'.

I did try, believe me!

The problem might be the "intermittent" part.
Currently, the phone line is quiet again & I have not suffered any disconnections since Friday.

When I phoned on Friday, the Plusnet agent said he would run some tests & post the results on my now very long ticket.
He hasn't done that, or he certainly has not posted any results or comments on my ticket.
So I posted an update myself yesterday to express my "disappointment".
I have not received a response yet, so that is why I have escalated it to Plusnet's Bob Pullen.

My other fear is that it now appears that both BT & Plusnet believe I have a very, very long line from the cabinet to my home.
I believe that Walter can confirm how close I am to the cabinet (geographically speaking).
Even when adding a massive margin for line detours (there are some), the actual distance appears to be way, way less than 1000 metres.

Hence the reason for BT resetting my profile at only 24 Mbps? (ADSL2+ speeds).
Either that, or the BT person who reset it remotely doesn't understand that I actually have a FTTC service & assumes it is actually still one of the ADSL variants.

As I am not now allowed to actually speak to BT myself (I was with BT, but the phone service was switched to Plusnet, purely to avoid the FTTC installation fee), I have to rely on Plusnet to do it for me.
Perhaps I was a bit naive, thinking that as Plusnet are owned by BT, it would still be easy to report line faults & generate some action from BT.

How the hell can I convince "them" that I have a line fault, unless it is apparent at the time of testing?
As far as "they" are concerned, I could just be one of those idiots that keeps disconnecting & reconnecting the modem with some wild idea that it might boost my speeds back up to "normal".

Considering the way that FTTC & phone lines are connected up, would a phone fault actually cause an issue with the FTTC provision?

Just for my understanding for when I attempt to chase this up yet again, what does LTOK actually mean?

"we may as well talk about the price of Cockles on Morecambe promenade." - I like it! a proper comment  ;D


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 07, 2011, 05:04:55 PM
@ paul,

Just to clarify the very long BT recorded distance is from the exchange to your home and that data should now be irrelevant, except for the phone part.
As far as I know BT have not yet implemented the same feature for FTTC to home distances. However the JDSU or EXFO meters BT engineers use does have a cable distance display but I have yet to see what a FTTC service looks like on the testers.

Can you add anything please RP ?

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 05:42:18 PM
@ paul,

Just to clarify the very long BT recorded distance is from the exchange to your home and that data should now be irrelevant, except for the phone part.
As far as I know BT have not yet implemented the same feature for FTTC to home distances. However the JDSU or EXFO meters BT engineers use does have a cable distance display but I have yet to see what a FTTC service looks like on the testers.

Can you add anything please RP ?

Kind regards,
Walter

@ Walter,

Are the operative words "should now be irrelevant"?

I am still curious why my original estimate of line speed from Plusnet was only 14.6 Mbps, yet I did actually achive 33 Mbps
At that time (early June 2011), BT's Infinity checker said FTTC wasn't even available in my area within the next 6 months.
Today at least it says:- 

"Faster BT Total Broadband
Great news! You can now get faster download speeds using our upgraded fibre optic network. Faster Total Broadband is only available on our Unlimited Broadband and Calls package.  14.6Mb" 

I still think that BT's & Plusnet's estimates may be based upon some inaccuracies in their database(s) regarding line length (more than 5000 metres?).

Plusnet's stance appears to be "we estimated 14.6, you are getting that, so bu@@er off & stop mithering!", totally ignoring the proven fact that I achieved a solid 32-33 Mbps for a couple of weeks
Are you aware of any reliable charts that provide FTTC speeds based upon line length from the cabinet?
I have searched everywhere to no avail.

I really wish I had asked the various engineers to show me the line length from their JDSU or EXFO meters. I had no idea they displayed that level of information.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 07, 2011, 05:45:07 PM
The 'LTOK' = Line Tests OK. Basically, when anybody reports a fault via their SP, they have to perform this line test. The problem is, it is a low-end/low frequency test that can't locate a high-resistnace fault. However, there is a new system under trial that apparently does pick up HR's.

This is what I'm guessing is your problem. Under normal conditions (ie-a good line) you resistance is measured down one wire (A-Leg) from the exchange, through your installation and back down the other wire (B-Leg) back to the exchange. Your resistance is then measured in dB's (Decibels). This figure will have been registered when you first had FTTC installed on the RRT tool.

Now then, when there is a 'HR fault', the thickness of the wire (poundage) will be less than what it should be generally due to corrosion. It can be half as thick, or less, than the nominal poundage. The problem is that the test voltages/currents will pass quite easily through this HR, thus returning a 'LTOK' result.

What can happen though with a HR, is that your attenuation should show a marked increase in dB's as the higher frequencies struggle to get through the HR and will show a mis-representation of being a 'Long line'. In a nutshell, ask your ISP to look at the RRT and extract the original attenuation and synch speed, and ask them to compare it to 'todays' readings. Then insist on an engineering visit.  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 07, 2011, 05:47:16 PM
Quote
Just for my understanding for when I attempt to chase this up yet again, what does LTOK actually mean?

Line Tested O.K.

Quote
crackly phone line since it was "fixed" therefore still a reportable fault?

With a bit of perseverance, you might be able to make the call to your SP's support desk whilst experiencing crackles on the voice line. In that case, the first thing to say is "Can you hear that?" Your next sentence should be "I wish to report a voice line fault. Intermittent noise on this line which, when it is tested remotely, shows up as LTOK."
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 07, 2011, 05:56:48 PM
Hi Paul,

I'm very sorry to tell you that BT in their infinite wisdom have now poisoned your line !

EDIT That's my terminology not BT's, but the line checker is obviously accessing the lower performance figure and telling you that FTTC isn't available in your case.
When the fault is cured it will be interesting to see how long it takes for the database to update your data again.

Here's another unhappy bunny, but we must say that there are plenty who haven't been as unlucky as you two have been.

http://community.bt.com/t5/BB-Speed-Connection-Issues/Infinity-line-checker-buyer-beware/td-p/62181 (http://community.bt.com/t5/BB-Speed-Connection-Issues/Infinity-line-checker-buyer-beware/td-p/62181)

Kind reagrds,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 07, 2011, 05:57:26 PM
burakkucat >> the first thing to say is "Can you hear that?"

I would have thought "Sorry I can't hear you for the crackling!"
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 06:27:06 PM
@ burakkucat

It WAS crackling when I phoned my ISP, but had bloody well gone quiet while I was on hold being constantly reminded that "all our agents are busy........."

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 07, 2011, 06:28:45 PM
Try rattling a crisp packet or sweet wrapper!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 06:39:51 PM

When the fault is cured it will be interesting to see how long it takes for the database to update your data again.



@ Walter,

At least one of us is still optimistic.

At the moment I am thinking:- if the fault is cured it will be interesting to see if the database ever gets updated

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 07, 2011, 06:52:43 PM
@ all of you,

I just want to say thanks to you all for your input into my issue, especially as I have only very recently registered on this forum.

I know it might send you to sleep, but I will keep you updated regarding any progress, or lack of!

You never know, my feedback might just come in handy for anyone else who experiences similar issues.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 07, 2011, 09:36:15 PM
I would have thought "Sorry I can't hear you for the crackling!"

An excellent idea, SS!  :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 08, 2011, 12:50:02 AM
@ razpag,

Talking about attenuation, when I was on ADSL, the downstream attenuation, as reported by my Netgear DG834GT modem/router, was always 63.5 dB, athough the real value could well have been quite a bit higher than that.

Apparently 63.5 dB is the highest value that most ADSL modems bother to report, as with a higher attenuation than that, it is quite likely that you simply cannot achieve a brodband connection.

For a number of years I was on a fixed rate 0.5 Mbps connection as that was all that any ISP was prepared to offer me due to BT's reported line length from the exchange.

I can't recall the date now, but a few years ago, BT started providing ADSL broadband over longer distances.

I took the plunge & switched to ADSL Max, up to 8 Mbps.
It was fantastic, my download rates doubled overnight to a whopping 1 Mbps!

Due to the high attenuation & SNR? values (around 12-15), I did have to use DMT.EXE though, to artificially lower my SNR, but I was able to achieve a reasonably stable connection, actually achieving 1.25 Mbps downloads on occasions, with the SNR artificially forced down to about 9.0.

I had a bit of an issue ages ago (maybe 2 years ago), when Plusnet had to contact BT (my phone provider at that time) due to a loss of broadband service. BT did some stuff on the phone line & replaced my old master socket with an ADSL v 10 face plate & told me that I could dispose of the filters that I had been using on all my telephone equipment. Problem solved.

Thinking back, I did also have an issue quite a few months ago when my ADSL upload speeds dropped to 96 K or lower.
This was fairly quickly resolved after I contacted Plusnet. It may well have been another intermittent fault though.
Strangely, around that time was when I was able to achieve my highest download speeds ever of 1.25 Mbps.

I always assumed that my high attenuation & SNR via ADSL were due to the distance to the exchange (approx 3 miles by road + any extra for line detours).

I switched to FTTC for 3 reasons:-

1) estimated speeds were 14.6 Mbps (proper broadband speed compared with the 1 Mbps that I was achieving via ADSL)
2) the distance to the cabinet via FTTC would be much less than the distance right back to the exchange via ADSL.
3) the monthly cost would be roughly comparable (or even less) for 40 GB monthly download limit to what I was already paying (usually around £20 / month when including the extra cost for exceeding my monthly 2 GB limit).

I was obviously delighted to find that my FTTC download speeds were actually around 32-33 Mbps (for the first couple of weeks).

We can now eliminate a big chunk of the line length from the exchange, as the only copper part (broadband-wise) is from the cabinet now that I am on FTTC. 

You have given me a few pointers & clear explanations for what I need to say when I contact my ISP yet again.

I am a bit concerned though, that if no "faults" are found, I will be charged £160 for each & every engineer's visit that I insist on.
From what you say about HR faults not being picked up by "normal" testing, this could explain why I am being told that my line is actually O.K. when in reality it might not be.

For the relatively short distance from my home to the cabinet, the indications (to me at least) are that there is a definite fault somwhere in the copper. It may well be intermittent & it may well be showing a mis-representation of being a 'Long line' false reading, forcing a reduction in my FTTC download speeds.
Proving it, when having to rely on "others" who have no real interest in it is a different matter.

I have to "blame" Plusnet & BT for my current predicament, because if they had never given me 32-33 Mbps downloads between them, I would have happily accepted the 14 Mbps or so that I am currently achieving, but for an "up to 40 Mbps" service...............?

If I do manage to get an engineer's visit booked, I will ask for the reference No. just in case it can be pinned to someone who already has a little background knowledge of the ongoing issues.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 08, 2011, 08:00:21 AM
@ Paul,

I'm sure RPs suggestions to get the telephone line investigated is the best and probably the only way forward.

However when all that has been done it might be useful to remember that you said you achieved the high FTTC speeds using the furnace modem and that has now been changed for a new cooler-running one. This might suggest the new modem has been de-tuned in some way so can't achieve the same speeds.

There's a bit more discussion on this subject here:-

http://forum.kitz.co.uk/index.php/topic,9503.0.html

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 08, 2011, 09:15:35 AM
Cheers Walter,

I'll see if Mr. Pullen gets in touch during today.

I would rather discuss these issues with him rather than a call centre operative who may just repeat things from a script.

Problem is though, I have not had a single disconnection since a batch of them on Friday (just after I phoned Plusnet to complain about disconnections & a crackly phone line).

I am just hoping the agent did actually run the tests that he said he would (at the time of the disconnections) & that he just forgot to post the results to my very long ticket.

The way I see it is that I potentially have 2 issues:-

1) Intermittently dodgy line - possibly really difficult to prove.
2) BT reset my profile at maximum ADSL speeds instead of maximum FTTC speeds - possibly easier to resolve, as long as the right person, with the right access authority, speaks to the right person at BT who would understand.

Even if the line does prove to be dodgy (broadband-wise), is it still the case that BT only have to guarantee voice communications?

FYI, the old modem was firmware version sp10, & so is the new one.

Edit: The old modem never got red hot, I would describe it more as quite warm. It may just have been coincidence that an ongoing "intermittent" line fault cleared itself (just like it has done this weekend) at the same time as I installed a desk fan.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Oranged on August 08, 2011, 09:33:48 AM
Is your connection "Infinity" or "Broadband with fibre" ?

The latter is an up to 15Mb product.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 08, 2011, 09:48:41 AM
@ Oranged

It is actually Plusnet's Value Fibre

Up to 40 Mb download / 2 Mb upload

I was achieving 32-33 Mb downloads.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Oranged on August 08, 2011, 10:59:49 AM
But it's either Infinity or Broadband with fibre as Plusnet (being "BT") don't have their own fibre network.

But I'm not sure if fibre resellers can buy in "Broadband with fibre" but if they can then it may explain the 14.6Mb connection.

"Broadband with fibre" isn't advertised, but I thought that it was only available if you phoned BT.

Might be worth asking Plusnet the question ?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 08, 2011, 11:36:33 AM
Hi
quote Due to the high attenuation & SNR? values (around 12-15),

The high SNR MARGIN value is NOT due to line length .

Normally you would have expected to connect with about 6db SNR margin . However if your line is seen as unstable then the DLM will increase the SNR margin (target SNR)  and or increase interleave to create a more stable connection.  The way this is determined is abit of a mystery,but it is based on hoe many disconnections and or how may errors  you have in 24hrs .There is more to it than that but that is the basic principle.
So the fact  you had SNR margin around 15db ,the maximum that is set as target suggest you have or had a noisy line .
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 08, 2011, 11:51:07 AM
@ JeffBB,

Can we assume that the standard (say 21CN) DLM logic is extended out to the remote FTTC DSLAM ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 08, 2011, 03:16:58 PM
Great news Folks (well, for me anyway),

Plusnet phoned me today.

I had a really pleasant & informative chat with someone who "understands" my predicament & without my prompting confirmed an ongoing "fault".

We discussed intermittent HR faults (thanks razpag), potential mis-representation of line length, my history of disconnections, possibly incorrect profile banding when it was reset last Thursday etc.

Another engineer visit is now booked for Tuesday 9th.

It was also confirmed that if not resolved quickly, the whole matter will be escalated within both Plusnet's & BT's management levels until it is resolved.

Apparently it takes 2 engineer visits within a short timescale before issues such as this can be formally escalated. Tomorrow's visit will be the 2nd within 5 days, so the criteria for escalation will have then been met.

I do wonder though how many people would have just shrugged their shoulders & thrown the towel in.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 08, 2011, 03:39:48 PM
@ Paul,

Many congratulations - so far. It does look as if you've rattled sufficient cages to get things moving.

I think I can assure you Paul that those in this erudite forum might be described by almost any if not all of the following:-

persevering, persistent, determined, dogged, strong-willed, tireless, indefatigable, resolute, patient, unflagging, staunch, steadfast, untiring, unwavering, unswerving, unshakable, unyielding, insistent; stubborn, intransigent, etc. etc. etc.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 08, 2011, 05:24:37 PM
That pesky b*cat has a confession to make. As he also frequents the Thinkbroadband fora as well this one, in the early hours of this morning he sent a brief PM to Bob Pullen, of PlusNet, to ask if he would please review this thread when time permitted. ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 08, 2011, 06:20:16 PM
Great result Mr Eagle. God willing, you will hopefully get an engineer who has been DSL faulting for some time, and is aware of simple broadband terminology akin to 'Interleaving' ?? ;)
Whilst making the brew and bacon butties for the engineer, it may be worth mentioning about suspected HR's and if he uses a HAWK,JDSU,EXFO,Tester 301C or, the antiquated Oscilloscope, for locating HR faults ?? This will hopefully see him perform this simple task, as it's surprising how many don't do this.

B*Cat, you couldn't drop the Queen a line and ask her where the blazes my OBE invitation has got to, could you ?? ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 08, 2011, 07:11:43 PM
@ razpag

Thanks for the all technical jargon such as CIDT, HR etc. It now appears that I actually know a bit about what I'm talking about.
Plusnet are one of the ISPs that have apparently chosen not to use CIDT themselves, but they are certainly asking BT to do it for me.

Don't you worry, I'll be asking for everything, including all the stats that the engineer can provide, that "proper" modems would provide for us.

BTW have you noticed the PM that I sent to you?

@ burakkucat

Bob hasn't actually responded to my own query (yet), but something has moved Plusnet's staff into turning this matter from a "No further action as everything is performing within specifation Sir" to a "We can definitely see an ongoing fault that will be escalated accordingly if it doesn't get sorted tomorrow" sort of issue.

@ all of you

I don't think I would have got this far without your help, I won't name names, to avoid embarassment, but I have also received quite a lot of help / information behind the scenes from some of you.

Once this matter is resolved (as I am now reasonably confident it will be), I will post a brief summary of the various issues & what actions are needed to get them resolved, as "others" may find them helpful in moving stagnant matters forward.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 08, 2011, 07:22:06 PM
Cheers B.E. 
Yeah, just seen your PM a few moments ago and have just responded.  :)

PS ... as I've said many times before, the people on here have an astounding base of knowledge, and there's not much (if anything) that can't be gotten to the bottom of, given time.  ;D ;D 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 09, 2011, 01:47:21 PM
God willing, you will hopefully get an engineer who has been DSL faulting for some time, and is aware of simple broadband terminology akin to 'Interleaving' ?? ;)
Whilst making the brew and bacon butties for the engineer, it may be worth mentioning about suspected HR's and if he uses a HAWK,JDSU,EXFO,Tester 301C or, the antiquated Oscilloscope, for locating HR faults ?? This will hopefully see him perform this simple task, as it's surprising how many don't do this.

It would have been good to have got any sort of an engineer, never mind one who knew what he was doing!
The appointment was for between 8:00 & 13:00.
Nobody has turned up.
Nobody phoned.
Plusnet have no idea when/if anyone will show up.

The bacon has now gone off & the bread has gone stale.

Surely my ISP & Bt haven't cocked things up between them (again)?
No, they are far to professional for that to have happened. It must be my fault >:(

Just to prove my memory isn't playing tricks on me, see the attached image.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 09, 2011, 03:36:54 PM
Disappointing is an understatement. >:(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 09, 2011, 03:43:16 PM
Surely my ISP & Bt haven't cocked things up between them (again)?
No, they are far too professional for that to have happened. It must be my fault >:(

FFS!
BT ran a basic line test from the exchange this morning & have now decided that a home visit is needed to carry out "special" HR testing by a "special" engineer.
It seems like they forgot to get in touch with Plusnet to actually arrange the visit though.

Anyway, the visit is now re-arranged (or arranged for the first time according to BT) for tomorrow morning.

Although it shouldn't be needed, the nice man from Plusnet is going to confirm this afternoon that BT are actually going to send the "special" engineer to do the "special" tests tomorrow.
He is also going to double check again 1st thing in the morning.

Watch this space.
On second thoughts, don't bother - nothing ever actually happens.

@razpag - Type of engineer: GEA SF. Does that look like the code for the "special" engineer?
It is the same code as the one used for today's non-visit.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 09, 2011, 04:07:48 PM
Perhaps Mr Pag has been seconded to your area! ;) (Wishful thinking, most likely.)

However, it does seem as though you will be visited by an OR SFI engineer -- which is most definitely movement in the correct direction.

Perhaps you would consider printing out this entire thread and allowing the engineer to read it when she/he arrives. As is so often the case, the actual "foot soldiers" who perform all the good work are the last to be provided with all the relevant information.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 09, 2011, 04:22:50 PM
Perhaps you would consider printing out this entire thread and allowing the engineer to read it when she/he arrives. As is so often the case, the actual "foot soldiers" who perform all the good work are the last to be provided with all the relevant information.


@ burakkucat

I printed it this morning, just in case, & I'll print any updates to it tomorrow morning.

With all the other stuff I have collated, I'll soon need another lever arch file (not that I've become obsessed or anything).

Paul
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 09, 2011, 04:36:52 PM
Hi Paul,

Ordinary mortals are not allowed to know BT fault numbers but you can always quote the Service ID and ask if the engineer can see any records there.

I've tried several times to get BT Openreach to associate a real local human being to a specific fault so that the end user can contact the engineer or possibly the control involved. (I have trained one local engineer to ring me up whenever he's called to a particular area as he knows I've probably been involved ! I can then brief him on the symptoms and we all get along very well. I also know the numbers of other locals so I can ask around for others having trouble.)

It seems unreasonable that the end user could well be wasting their holiday leave, or perhaps their earning time, whilst waiting for a non event. Given that we're talking about a comms company it wouldn't stretch the imagination to much to have a set of pseudo mobile text numbers that could be assigned specifically for faults and have them auto-directed to the person responsible. First thing on shift all faults would be pointed at control and as each engineer logs in to his / her next fault the number is redirected. If text were used the lines won't become overburdened.

I fully expect RP to ever-so-politely tell me to get lost and not to attempt the suggest real practical ways of "improving the customer experience". However if we could get the matter addressed RP would not be facing the front end of a 12 bore for every other visit he makes. (Some exaggeration here !)

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 09, 2011, 04:58:14 PM

It seems unreasonable that the end user could well be wasting their holiday leave, or perhaps their earning time, whilst waiting for a non event.

I fully expect RP to ever-so-politely tell me to get lost and not to attempt the suggest real practical ways of "improving the customer experience". However if we could get the matter addressed RP would not be facing the front end of a 12 bore for every other visit he makes. (Some exaggeration here !)


Thankfully, I do still have internet acces & am able to work from home via VPN (although I have another ticket on the go regarding Plusnet's possibly incorrect VPN traffic management, currently suspended until this issue has been sorted once & for all).

I won't be shooting the engineer as it clearly will not be his/her fault.

I work for a very large construction related company, dealing with responsive repairs (amongst other things).
Our "customers" are officially encouraged to contact our service desk regarding urgent works, but off the record, I am more than happy for my team of surveyors to take mobile phone calls directly, to save time.
We cover a large patch & many times it saves them coming back to the office just to find out they have to go back to where thay have just come from, & in many cases, they can simply organise a relevant contractor to deal with the problem anyway.

I have been dusting off the cartridges though for as sure as eggs are eggs, "someone" will be in the firing line.

My priority is to get things fixed first though.

Paul
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 09, 2011, 06:17:37 PM
Surely my ISP & Bt haven't cocked things up between them (again)?
No, they are far too professional for that to have happened. It must be my fault >:(

FFS!
BT ran a basic line test from the exchange this morning & have now decided that a home visit is needed to carry out "special" HR testing by a "special" engineer.
It seems like they forgot to get in touch with Plusnet to actually arrange the visit though.

Anyway, the visit is now re-arranged (or arranged for the first time according to BT) for tomorrow morning.

Although it shouldn't be needed, the nice man from Plusnet is going to confirm this afternoon that BT are actually going to send the "special" engineer to do the "special" tests tomorrow.
He is also going to double check again 1st thing in the morning.

Watch this space.
On second thoughts, don't bother - nothing ever actually happens.

@razpag - Type of engineer: GEA SF. Does that look like the code for the "special" engineer?
It is the same code as the one used for today's non-visit.

Paul.

OMG !!! I can really only  comment that this has been shambolic in the way it has been handled. My thoughts are, your fault (For some reason) has been passed to the Frames Staff as a FRSFI task. This consists of the Frames engineer checking the 'circuit mapping' (making sure you are on the correct equipment ports) and that's pretty much it. Well gone are the days, when they had a 'Presto tester' to check for bog-standard synch and errors. So once the mapping checks out, the job is 'kicked' to us.

GEA SF = Generic Ethernet Access Special Fault. In other words, a Fibre Broadband fault.

Although my wife thinks I'm 'special', when it comes from the lips of others, I can't help but think they're perhaps teasing me ??  ;D

Never mind the riots, I'm going to be praying for you to receive an engineer tomorrow Mr Eagle.  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 09, 2011, 06:42:43 PM
Hi Paul,

Ordinary mortals are not allowed to know BT fault numbers but you can always quote the Service ID and ask if the engineer can see any records there.

I've tried several times to get BT Openreach to associate a real local human being to a specific fault so that the end user can contact the engineer or possibly the control involved. (I have trained one local engineer to ring me up whenever he's called to a particular area as he knows I've probably been involved ! I can then brief him on the symptoms and we all get along very well. I also know the numbers of other locals so I can ask around for others having trouble.)

It seems unreasonable that the end user could well be wasting their holiday leave, or perhaps their earning time, whilst waiting for a non event. Given that we're talking about a comms company it wouldn't stretch the imagination to much to have a set of pseudo mobile text numbers that could be assigned specifically for faults and have them auto-directed to the person responsible. First thing on shift all faults would be pointed at control and as each engineer logs in to his / her next fault the number is redirected. If text were used the lines won't become overburdened.

I fully expect RP to ever-so-politely tell me to get lost and not to attempt the suggest real practical ways of "improving the customer experience". However if we could get the matter addressed RP would not be facing the front end of a 12 bore for every other visit he makes. (Some exaggeration here !)

Kind regards,
Walter

Walter

Seriously mate, I have no qualms with anybody trying to suggest 'ways to better the EU's experience', as it would hopefully make my one-to-one contacts with the EU's slightly more civil than some we come across.  ;D As I say, I completely understand the level of frustration the EU has to deal with.

However, the mano-y-mano scenario you propose may work well in tiny rural patches, and I dare say it is something my colleagues working in the wilds of Scotland actually employ. It's not really frugal or business-like though, to try and roll-out a 'hap-hazard' way of EU interaction. I don't mean that in a cynical sense btw Walter, I mean it's too open to abuse if you like ?? I'm finding it hard to put into words what I mean, but when the higher echelon implement a 'system of use', or a methodology, it has to be in the guise of one cap fits all.

There could be all sorts of cries of 'foul play' if we were to use your suggestion Walter, and I reiterate, I'm on your side here. :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 09, 2011, 07:46:17 PM

Never mind the riots, I'm going to be praying for you to receive an engineer tomorrow Mr Eagle.  ;D


@ razpag

They do say that patience is a virtue.

Under the circumstances, I think I have been quite patient so far.
This has been going on & off for over a month now. Although I imagine a lot of users have to wait a lot longer than this.

However, I am now becoming slightly less virtuous as each day goes by.

On the off-chance that physical line "faults" cannot ever be pin-pointed due to their intermittent nature (I have not had a single disconnection or crackly phone line since Friday), is it at all likely that the whole length of copper from the cabinet to the home will be replaced (at no expense to the end user)?

I would guess that the sheer expense would more or less rule that out.

And, just for the record, would the engineer be able to provide me with the full set of stats that are currently hidden away in the modem's locked/disabled interface such as sync speed, attenuation, interleaving, SNRM etc.?

I would also dearly love to know the "reported" copper line length from the cabinet to my master socket, now that I can ignore the fibre length from the exchange to the cabinet.
Do you know if that can be gleaned from the JDSU or whatever the engineer uses?

BTW, I like the Mr. Eagle references - much better than Baldy :)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 09, 2011, 08:09:24 PM

Never mind the riots, I'm going to be praying for you to receive an engineer tomorrow Mr Eagle.  ;D


@ razpag

They do say that patience is a virtue.

Under the circumstances, I think I have been quite patient so far.
This has been going on & off for over a month now. Although I imagine a lot of users have to wait a lot longer than this.

However, I am now becoming slightly less virtuous as each day goes by.

On the off-chance that physical line "faults" cannot ever be pin-pointed due to their intermittent nature (I have not had a single disconnection or crackly phone line since Friday), is it at all likely that the whole length of copper from the cabinet to the home will be replaced (at no expense to the end user)?

I would guess that the sheer expense would more or less rule that out.

And, just for the record, would the engineer be able to provide me with the full set of stats that are currently hidden away in the modem's locked/disabled interface such as sync speed, attenuation, interleaving, SNRM etc.?

I would also dearly love to know the "reported" copper line length from the cabinet to my master socket, now that I can ignore the fibre length from the exchange to the cabinet.
Do you know if that can be gleaned from the JDSU or whatever the engineer uses?

BTW, I like the Mr. Eagle references - much better than Baldy :)

Paul.

Ha ha , hadn't thought about the 'Baldy' angle. ;D

I think you've sort of answered your own question regarding swopping the whole cable out, due to intermittency. Not a Jack Pallance i'm afraid. As I've hinted at in other threads, Openreach have to employ a one cap fits all process, can you imagine the price of replacing lengths and lengths of cable nationwide on the whim of an engineer ??? It's a continual scrap to get our planners to 'cough up' even when we do fault it down to a particular length. They too are micro-managed to the hilt over capital spend.

Hands up time regarding the 'Full set of stats' you mention ?? I've never attended a FTTC repair, but from the installation side of the fence, which is exactly the same TBH, he will be able to provide you with the usual stats that are of interest, ie- Attenuations, SNR's,Synch speeds .... etc.

As you were, Mr Eagle.  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 09, 2011, 10:18:31 PM
Suggestion -- When the engineer plugs in his/her JDSU, EXFO or what-not, why not have your camera to hand and ask if you could photograph the relevant screens, so that you have a record of the current statistics?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 09, 2011, 10:33:24 PM
Suggestion -- When the engineer plugs in his/her JDSU, EXFO or what-not, why not have your camera to hand and ask if you could photograph the relevant screens, so that you have a record of the current statistics?

Cheers burakkucat,

That had not even crossed my mind.
Sometimes the simplest ideas are the best ones.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 10, 2011, 12:00:00 AM
Hi Paul,

I have used my mobile to take pictures of the JDSU pages which can help. HOWEVER I suggest it's important that you get the engineer to unlock the actual VDSL2 modem that you use. The reason I say that is that on standard ADSL1 lines the JDSU always seems to connect at lower sync speeds than the 2700 HGV Business Hub. I must stress that these observations are on very long and noisy lines but I have known I think 3 now where the JDSU hasn't managed to sync even after 20 minutes or so but the 2700 might take say 5 minutes but always manages the minimum speed sync.

Unless you can tell me otherwise, I think the jury is still out on this latter replacement modem. I.e. it has never been as fast as the original "furnace" one ? I don't suppose we'll be told but I would be very keen to know what design modifications were made to reduce the overheating. If those changes have reduced the potential speed, then all subsequent swap-outs will probably behave similarly.

If this were a little cheaper I'd be tempted to get the Zyxel modem asbokid described here

http://forum.kitz.co.uk/index.php/topic,9707.msg196200.html#msg196200


Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 12:26:32 AM
Hi Walter,

The "furnace" modem returned speed test results as low as 7.97 Mb down & 0.66 Mb up.
My profile was getting lower & lower, no doubt due to the disconnections

When my profile was reset by BT at 24 Mb Thursday 4th August, the new modem was connected, & for a few hours I achieved downloads up to 22.7 Mb & uploads at 1.67 Mb.

By Friday morning, downloads had dropped to around 14.5 Mb with uploads still at 1.66 Mb.
I have suffered no disconnections at all since Friday & although I haven't saved the results into a spreadsheet yet, they are still around 14.5 down & 1.66 up.

Some dated results attached.

BTW, both modems are firmware version SP10 (I believe that is the most recent version until BT's version 'B' modem is released, whatever it happens to be).

To be honest, because I still had some disconnections & crackly phone line after the modem had been replaced, I'm not not now 100% convinced it was an overheating modem issue at all, but rather an intermittent line issue all along.

Hopefully, all will be revealed in the morning.

Paul.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 10, 2011, 01:04:13 AM
If this were a little cheaper I'd be tempted to get the Zyxel modem asbokid described here

http://forum.kitz.co.uk/index.php/topic,9707.msg196200.html#msg196200

@ Walter -- If only Arthur Daley was still in the Import/Export business, he could have a "nice little earner" by importing the Dare Tech DB120-B2+ direct from China . . .  ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 10, 2011, 11:09:35 AM
Walter, not sure 100% what you mean buy, ' get the engineer to unlock the VDSL modem', but if it's anything more than taking it out of a box and plugging it in, we don't do ANYTHING more with the VDSL modem.  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 10, 2011, 11:23:38 AM
Hi RP,

This is perhaps the difficulty as (I believe) the EU can't observe the modem statistics as we can with most ADSL 1 & 2 modems. However there must be some department within the BT Group that is able to observe the modem statistics. I wonder if you'd be allowed to enquire who might have such access and whether the end users could also please be given such access. At present there might be a suspicion that parts of BT are trying to hide the performance of the D side lines.

@ Azzaka, As a CP are your able to access the standard BT VDSL2 modems ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 11:31:24 AM
Mornin' All,

Well, the "special" engineer turned up this morning & everything went really well.........NOT

He was carrying another shiny new Huawei Echolife HG612 modem under his arm as he walked down to the house.
My suspicions regarding his intentions for today's visit were immediately raised.

After the usual pleasantries were over. he scratched his head for a while, looking at the shielded, twisted pair, high quality, high speed "data" cable going into the back of the FTTC socket next to my desk. Eventually he asked "Where is your master socket then, & where did that cable come from".

I told him it was my own cable that the original FTTC installation engineer had hard-wired from the upstairs socket when he relocated my master socket from upstairs to the one he was now looking at. I showed him the upstairs socket that now just has a single telephone only outlet.
 
I aked him if he was aware that the modem had only been replaced last Thursday & I told him that I had been assured that today's visit had been arranged for an investigation into the intermittent disconnections & crackly phone line, & to especially investigate high resistance issues.
He responded with "No, I'm here to see that you are getting at least a 15Mb connection, because that's all we have to guarantee, & to replace the modem.

He would not really listen to a summary of the ongoing issues, or look at my "evidence" of decent speeds.
His only comment when I told him I had recently suffered a complete lack of phone & FTTC service for 4 days was "Ah, so the line's been fixed then".
He certainly did not accept that I still have a suspected intermittent "fault".

Anyway, he unplugged the 6 day old modem & plugged his JDSU HST 3000 meter into the master socket.

I asked him if he minded if I photographed the various screen displays because that was the only way I could obtain a record of the line stats due to the BT modems being locked against end-user access.
After he looked at me as though I was from Mars, he shrugged his shoulders & said, "Well, I suppose so".

After a while he said "There you go, your Max Rate is 22 Meg". See the attached photo.

I asked if he would be requesting a profile/line reset to get it back up to around 30 Mb.
The answer was that no, he wouldn't be doing that because 22 Meg is all my line can provide.

I asked if he would be doing any "special" high resistance or other line testing to investigate the intermittent "faults".
The answer was again no as the line tests OK (LTOK).
When I asked if the display actually showed any high resistance or other issues, again he said no, it is all O.K., it would either pass or fail.
As I had misplaced my reading glasses (what an absolute idiot!!!!) I couldn't see the display & will have to just rely on the single (not very clear) photo which again, I couldn't see clearly on my camera.
I asked him what the attenuation level was then. The response was that it was O.K.
I asked him if it was high.
He said it was O.K.
I asked if it showed a value.
He said it was O.K. & that it would simply either pass or fail.
I asked about the low max rate of 22 Mb.
He said it was OK.
I asked why it wasn't 30+ Mb as on the day of installation.
He said it was O.K. & that's all I can expect my line to provide.
I asked if he knew the distance from the cabinet.
He said it wasn't too far.

Seems to be a bit of a pattern devoloping here.

I asked if the distance (either physical or potentially mis-represented distance due to potential high resistance) could be the cause of the now low max rate of 22Mb, or could it be likely that the regular disconnections etc. had forced a temporarily lower rate via BT's automated DLM at the cabinet.
He said it was O.K. & that's all my line can provide. He opened up a bit then & said it is probably because of the aluminium in the cables.
When asked if that's the case then, how come I solidly achieved higher speeds for the first couple of weeks, the response was that that's all my line can provide & I would have got the full 40 Mb on installation that has now been trained down to 22Mb.
I asked if he knew that the cables were aluminium, or just suspected it.
He said they are probably aluminium.
Another shrug of the shoulders came when I said the original installation engineer had told me it had NEVER achieved the full 40 Mb, but it was around 35 Mb when first installed. He also commented that it MUST have been at 40Mb for a while.

He did add however that he didn't fully undertand these things & that anyway, the British Army has now been drafted in to install FTTC, not just the cabling, but the installations in the home too.
He further added that he only gets the crappy jobs now.

Just before he left, the engineer told me that today's new modem is the new improved version 2B that will sort everything (phot attached).

1) Did I actually get the right sort of engineer this morning?
2) Is the very limited information that he gave me actually correct?
3) Has any of what the engineer done this morning actually addressed my potential intermittent line "fault"?
4) I have asked Plusnet to provide both BT & me with proof that my line was solidly achieving 32Mb for the first couple of weeks & surely it should now have "trained" itself to that level but for the intermittent disconnections/crackly line  "fault".
5) What the hell, if anything, can I do to get this sorted once & for all. Virgin cable is not available in my area. BT provide the infrastructure, so any ISP would be in the same position as Plusnet.
I was promised this would be escalated if not resolved. But how?

The saga continues.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 12:03:54 PM
@ razpag

The photo from the JDSU is not too clear, but what can be deduced from the values:-

                             UP                    DOWN                 
Actual Rate             1996K                22648K
Max Rate                5212K                22662K
Capacity                   38%                  100%
SNR                      12.9 dB                 5.9 dB
Line Atten              52.9 dB               30.2 dB

a) Does this "appear" to be a very long line? If so, could you give a rough estimate in metres?
The Kitz calculator suggests 2.2km downstream (30.2 dB Line Atten) & 3.8km upstream (52.9 dB Line Atten)
This is for ADSL though - so I don't know if it is the right estimator & how relevant that would be for FTTC anyway.

In reality I live around 0.4 miles (roughly 0.65 km) from the cabinet by road, not in a straight line (I do know the line detours a bit though).

b) Is 22662K indeed the correct Max Rate?
 
c) Is it usual to see such a difference between the SNR & Line Atten for upstream & downstream?
I now recall that I did have an issue about 6 months ago on ADSL when my upstream dropped to around 96K for a few days, even though my downstream was at its highest level of 1250K. When the upstream reverted to its usual level (just a guess at 348K, my downstream went back down to 1000K).

d) Could this morning's engineer have actually told me the reported line length from the cabinet?

e) We didn't even get round to discussing Interleaving. Could the engineer have told me whether it was on or not?

f) Even if interleaving is set at HIGH (as Plusnet told me it was a while ago), would it affect the Max Rate, the Actual Rate, or both?

g) Do any of the values suggest there is an actual line "fault"?

h) Are you aware of any improvements gained from the version 2B modem?

i) Am I just asking for too much i.e. do I now have the maximum stable speed that my line will ever provide & is it time for me to put up & shut up?

P.S. My upload speeds are capped at 2Mb with the "Value Fibre" package that I am on, so I am not querying upload speeds at all.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 10, 2011, 12:59:56 PM
@ Paul,

Comparing the JDSU VDSL figure to those of ADSL the attenuations "look" transposed. Note also that the attenuation seems only to be measured properly from the far end. I.e. the downstream observation from your home should be reasonably accurate whereas the upstream is usually an approximation of about half the downstream. My guess is that JDSU Tests are done with the entire line connected (as your service is a SMPF one - Shared Metallic Path Facility. I.e. your telephone service is still provided over the whole length of line back to the exchange. (Note FMPF {Full MPF}, which is available to some independent Communication Providers, has the D side line isolated at the PCP so any telephony services provided by them use a form of VOIP telephony.)

You might ask the next visiting engineer if he can do a TDR test if he's allowed to. http://en.wikipedia.org/wiki/Time-domain_reflectometer

However we have had discussions before here suggesting that the JDSU instrument is possibly not the best device for this test.

Here's a JDSU example on a long line as you can see.

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 01:12:28 PM
Hi Walter,

The "special" engineer was supposed carry out a CIDT test this morning that identifies the "faults" such as high resistance that basic tests can't identify. (please see the attached .pdf, although I suspect that personally you will have read this previously.

I don't know whether his JDSU meter did that this morning or not. Any idea razpag?
You may have gathered that the engineer wasn't particularly helpful or forthcoming with his responses this morning.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 01:17:22 PM

Here's a JDSU example on a long line as you can see.


Hi Walter,

Did you mean to attach an example from another JDSU, or were you talking about my JDSU example?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 10, 2011, 01:56:25 PM
Hi Paul,

It was supposed to be another one which was too large but I'll have another go.

K R
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 10, 2011, 06:44:25 PM
Hi Walter,

The "special" engineer was supposed carry out a CIDT test this morning that identifies the "faults" such as high resistance that basic tests can't identify. (please see the attached .pdf, although I suspect that personally you will have read this previously.

I don't know whether his JDSU meter did that this morning or not. Any idea razpag?
You may have gathered that the engineer wasn't particularly helpful or forthcoming with his responses this morning.

Paul.

Hi BE

Firstly, I'm not going to comment on the engineer other than, it sounds like he's basically doing what's been asked of him via our training courses. I'll have to leave that one there i'm afraid.

Now then, the JDSU info you've posted up does indeed 'show' a good test, and that you are receiving the 'max' expected for your line. What has really made my brain hurt, is Walters comments about the attenuation figure being the full length of the 'copper pair' from exchange to premises. Now I've racked this over in my head for about an hour, and I can't see how the attenuation calculator within the JDSU can measure through the DSLAM, so it's my guess (and that is all it is), that the attenuation reading is from the Cab to the premises. If my guess is right, then you have a helluva high reading if you are positive you only live 0.5 miles away from the Cab ?? This kind of integer would also fit in with a large drop in synch speed, from 40Meg down to what you are receiving presently ??

This truly is puzzling, as you are certain you've had higher speeds of 35Meg which would also fit in with a relatively short distance drop from 40Meg over 0.5 miles ?? It's bizarre. The comment about everyone starts at 40Meg and the DLM drops accordingly is not right either. You get what you get and DLM does minor tweaks, not 12/13 Meg drops from 35 to 22 meg !!!!

The only rationale I can produce, is that you still have an HR fault, this is giving the DLM the impression you are 30.2dB from the exchange and as such, it has given you the synch speed it determines is suitable for this distance and quality of line. The tests carried out by the JDSU that you have shown will not 'see' a HR. Only the TDR function within the JDSU can do that, when testing back to the exchange with voltage applied. Again, i'm not 100% sure about the attenuation figure as to whether it's the whole of the 'pair' or just from premises to Cab. I've not taken much notice when on installation tasks, and as the engineer stated, they've now employed ex-services personnel and the apprentices to cover ALL FTTC/FTTP/Managed Install work. We experienced, multi-skilled engineers don't get a look in these days. It's wrong on so many levels but that's BT politics for you.

Sorry I can't be of much help mate, I really wish I could. :'( 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 10, 2011, 09:10:08 PM
Hi RP,

I too am working in the dark just on the theoretical approach. As Paul's BT recorded line distance is 5283 m to the exchange and the attenuation is high I'd assumed the opposite that it was measuring the whole copper pair, but possibly with some strange effect due to the DSLAM "tee off" being in the FTTC. It also seems strange that the attenuation figures seem abnormal and perhaps reversed ?

Paul's D side pair is under 600 m in length but neither of us know whether aluminium is involved.

As you haven't mentioned it, I assume that you are not instructed to disconnect the E side pair in the PCP before doing FTTC JDSU tests ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 09:15:35 PM
@ razpag

The way I understand matters is as follows (please correct me wherever I have got it wrong):-

Via ADSL, the DSLAM is located at the exchange.
Via FTTC, the DSLAM is located at the FTTC cabinet, effectively bringing the exchange a lot closer to the end users (for broadband purposes).
The broadband speed at the FTTC cabinet is currently restricted to 40 Mb (for now), & will always be a minimum of 40 Mb
The telephone service still comes via wires (copper or ally, or a mixture) all the way from the exchange to the old cabinet
The broadband fibre & telephone wires only join up at the FTTC cabinet
The broadband & telephone services are then delivered to end users from the FTTC cabinet via wires
The wires between the cabinet & the end user can often take quite a detour, increasing the line length that actually affects broadband speeds substantially in some cases
The overall length of the wires from the cabinet to the end user has a distinct effect upon Line Attenuation
Line attenuation can additionally increase due to the conductive material the wire is made from e.g. copper conducts much better than aluminium, the thickness (poundage) of the wire, the quality of any joints, corrosion, water ingress, temperature.
Line Attenuation directly affects the broadband speed at the end user's master socket i.e. the longer the line, the higher the attenuation & the lower the broadband speed at the master socket
End users very close to the FTTC cabinet (within 100m or so) can expect the full 40 Mb, less any general overheads. The usual full speed is around 39 Mb at the master socket.
Broadband speeds graually decrease over a line length of around 700m - 800 m, then rapidly decrease thereon after as the Line Attenuation increases due to the general resistance within the wires.
At a distance from the cabinet of say 750 m, assuming the wires are in good condition, a reasonable line speed of 35 Mb can be expected. Allowing for general overheads, an achievable & sustainable download speed of 33 Mb can be expected, suject to contention.
Signal to Noise Ratio also affects line speed. A high SNR = good, a low SNR = bad.
Electrical noise can be introduced into the line from various sources e.g. induction from street lights, nearby power cables, radio frequency transmissions, fridge motors etc.
SNR is usually at its best during the daytime. In the evenings, SNR can lower substantially
Line speeds & therefore upload/download speeds are continually & automatically adjusted by Dynamic Line Management (DLM) to suit prevailing line conditions.
Following initial installation, the DLM will allow the highest speed possible to the master socket, constantly checking for things such an increase in attenuation, a lowering of SNR (the more interference, the lower the SNR), regular disconnections for whatever cause.
To keep the line working, the DLM will lower the line speed to restrict errors & maintain stability.
Over the first 10 days or so, the line speed usually trains & stabilises at a sustainable value, although a succession of incidents such as repeated disconnections can restart the line training period at any given time.
Line speeds are lowered quite quickly by the DLM, & via FTTC can take around 10 days or so to recover to the previous sustainable speeds.

Now, in my own circumstances, for the first couple of weeks, I solidly achieved download speeds of 32-33 Mb, against the installing engineer's confirmation of a line speed (Maximum Rate) of 35(ish) Mb.
Following a number of disconnections & a complete loss of phone & broadband service for 4 days, the line speeds eventually reduced to around 8.5 Mb.
Every now & then the line would pick up speed, but would be reduced a short time later by another succession of disconnections.

Having sustained download speeds of around 32-33 Mb for a couple of weeks, my line can be considered to have completed its training period, & given another suitable training period with very few disconnections, high resistance, other interference etc. may be expected to gradually regain those sort of speeds.
this may take another 10 days or so.

It is my understanding that DLM adjusts line speeds "on the fly" & does not in itself cause disconnections.
I assume therefore that the disconnections have been intermittently caused by other unknown events.
There does not appear to be a pattern to these events.
The weather can be warm & dry, or wet, cold & windy.
It could be during the daytime or at evenings, or even the early hours of the morning.
A number of days can pass with no disconnections, sometimes spanning whole weekends.

My line currently does appear to have quite a high attenuation in comparison to its likely overall physical length. This suggests high resistance, but of an intermittent nature, otherwise, surely I could never have achieved the initial high download speeds.

It is however impossible to monitor line/connection statistics via the BT modem.
The cynics amongst us may well believe this was an intentional move by BT, purely with the aim of concealing the facts that FTTC isn't quite ready for the market as advertised & is only really fit for purpose for anyone living within 100m or so of the FTTC cabinets.

Maybe the new & improved version 2B modem will be nore resilient to these intermittent events.
As the "special" engineer didn't test the quality of the line in any way, the question regarding general line quality cannot be answered at this stage.

In your opinion, is this matter really worth pursuing? I won't give up if there is a reasonable chance of a permanent reolution, but I don't wish to keep flogging a dead horse.

In many respects I should be happy with my current download speeds of around 22 Mb (it is after all a lot more than many users can achieve), but in reality it is only just over half the speed that FTTC promises.

Sorry for the length & rambling nature of this post. Do you have any experienced comments or advice for me?


Paul

Edit: Have BT or Plusnet manually introduced a Max Rate cap onto my line, that could/should now be removed to at least test the line at full speed again?
The engineer said he didn't test the speed as it leaves the DLM at the FTTC cabinet as that wasn't his job.
Would this be a basic test that "special" engineers should do as part of an investigation into poor speeds at the end users master socket? I know it would be if I was investigating for example poor water pressure at a tap. I would first check that the pressure at the source (mains) was O.K., especially if it was a known fact that it had been good pressure at the tap at one time.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 10, 2011, 09:19:46 PM
Walter

No mate, once we've tested that we are receiving the 40/2 or 40/10 at the PCP, we connect through the old/existing E-side carrying the dial tone, pick that and the combined DSL signal up in the 'return' cable and put it through to the on-going D-side. (As I'm sure you already know Walter, just info for those who don't).

After leaving the PCP and visiting the EU's, all testing is carried out at the premises, ergo no disconnecting of the E-side.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 10, 2011, 09:36:48 PM
BE .......... reading your post, you are now well-versed in the shennanigans that make up DSL mate  ;D.

All that is correct, barring possibly the comment about SNR. That is all dependant on 'factors'. Your SNR of 5.9dB on the DS is pretty much perfect, if it was higher, I would suspect some kind of fault-type condition. However, if you live very close to the FTTC a SNR of 15dB is also very good. I think Jeff is the man to explain it if you need a more in-depth angle on it. :).

I genuinely cannot offer up any more advice that may help you. I'm as baffled by this as you are ?? I can't accept that you have gone from 35 Meg stable synch to 22 Meg via DLM !!!! It's just too large a jump imo.

Having read your post though, you put it quite succinctly as to how the DSL drops over attenuation (in laymans terms that is ....... the real reason is that it drops due to the ammount of 'noise' spread over the frequency bins, and how much data it can load in each bin), and it really is as simple as that, the longer the line the higher the attenuation !! I was maybe over-thinking the situation in my earlier post. Your line basically 'starts' at the FTTC now, so your attenuation should be low for a D-side of just 0.5 Miles ??!! As I say, something doesn't quite add up. :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 10, 2011, 09:39:50 PM
Just seen your 'edit'.

That is the only thing that makes sense, that there is a 'cap' applied. But then again, I would expect to see a lot higher SNR if that was the case, roughly 20dB and above.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 09:43:23 PM

Having read your post though, you put it quite succinctly as to how the DSL drops over attenuation (in laymans terms that is .......


@ razpag,

Sorry about the laymans terms. I didn't want to confuse you with a load of technical jargon.  :lol: :lol:

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 10, 2011, 09:46:55 PM
You jest sir, but with your learning accumen you'll probably be at BT Martlesham next week with our boffins !!! ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 10:12:18 PM
Just seen your 'edit'.

That is the only thing that makes sense, that there is a 'cap' applied. But then again, I would expect to see a lot higher SNR if that was the case, roughly 20dB and above.

I'll ask Plusnet tomorrow about a possible cap at their end. If I'm thinking correctly, that wouldn't cause any effect on SNR, would it?
With Plusnet, a manual adjustment to user profiles has to be made after installation of FTTC.
e.g. When mine was installed, I had to wait for around 1 hour before I got the full whack that my line could deliver.
That was 32-33 Mb, just in case I haven't mentioned it before ::)
I was just about to phone Plusnet to ask for a profile nudge when they phoned me to say they had just nudged it.

When the BT modem was replaced last Thursday, BT said they had reset my profile at their end to the Max & if that was only 24 Mb at my end, it was because that was all my line could deliver.

It may just be that Plusnet now have to manually reset my profile back to the Max at their end.

That sound too simple though, so I'm not putting a week's wages on it being the answer.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 10, 2011, 10:33:26 PM

I can't accept that you have gone from 35 Meg stable synch to 22 Meg via DLM !!!! It's just too large a jump imo.


I still don't know whether or not interleaving affects line speeds & I can't find a clear answer anywhere. I believe it affects download speeds though.

At one stage Plusnet informed me that interleaving was automatically set at HIGH for downstream & ON for upstream due to the disconnections.

Is interleaving a separate stabilisation measure from DLM, or is interleaving the effect of DLM?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 10, 2011, 11:59:08 PM
A Paul & RP,

Well done for summarising things so well.

A small point re attenuation has been hinted at Viz the attenuation value varies with the tones (Frequencies) involved.
(E.g. with the 2Wire it reports an attenuation at 300 kHz as well as what I understand to be an average attenuation, which is usually a little lower, over the entire frequency range used.)

I assume that on an exchange based service the JDSU attenuation calculation must observe the whole line length and the front end components on the line card etc within the exchange.
Similarly with a FTTC based calculation there must surely be the line card com ponents within the FTTC DSLAM as well as perhaps the remaining voice component back to the exchange if the filter cct. is misbehaving. However in both cases the active frequency range starts at tone 6 for the upstream.

Another point is that just as there is often a difference in the attenuation reported on the same line when it changes from ADSL 1 to ADSL 2, the same logic must apply when it becomes VDSL2 as the potential frequency range has increased. Thus you might expect a much larger variation in attenuation if going from a long ADSL1 line to a much shorter VDSL2 line.

How all this might reflect into operational maintenance and fault finding procedures is something I doubt if anybody here can tell us yet. In an ideal world it would be very valuable to change Paul's FTTC DSLAM port but I very much doubt if that has been developed in the new FTTC engineers' bible ! In any case that would presumably involve instructing the DSLAM to change the active port for the particular cct ID.

Can anybody else add more to this please?
__________________________________

See also Kitz's explanation

 ~ Tones which aren't in use.

Certain sub carrier channels are not used. Some of these are laid down in the g.DMT standard, whilst some others may depend upon the DSLAM/MSAN manufacturer and vary slightly.
Common tones not in use are:-

DC (First Tone). Tone 0.
Guard Band (Tones 1 to 5 < 25.875 kHz). Tone 1 POTs. Tones 2-5 prevents cross talk between POTs + adsl.
Guard Band (Tone 32 - 138kHz). Prevents cross talk between upstream and downstream data.
Nyquist frequency (Final frequency tone)
Upstream Pilot Tone. (Tone 16 - 69kHz)
Downstream Pilot tone. (Tone 64 - 276kHz).
Annex_M Stop Band. (Tone 59 - 254kHz). ADSL2+ Annex_M only.
DSLAM Specific Tones (eg Tones 476 - 499 2053kHz-2156kHz on Be*/02 MSANs only).
Your router will also mark any sub-channels where the SNR is too low to carry data as unusable.

Read more: http://www.kitz.co.uk/adsl/adsl_technology.htm
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 11, 2011, 12:19:21 AM

How all this might reflect into operational maintenance and fault finding procedures is something I doubt if anybody here can tell us yet. In an ideal world it would be very valuable to change Paul's FTTC DSLAM port but I very much doubt if that has been developed in the new FTTC engineers' bible ! In any case that would presumably involve instructing the DSLAM to change the active port for the particular cct ID.


Hi Walter,

Would your suggestion be the L & S (Lift & Shift) operation?

I was wondering if that could be an option now.
If indeed my profile is now stuck, either at BT's end or at Plusnet's end, with both of them saying they are giving me the Max Rate possible, I am sure I have read somewhere that a L & S operation can usually free things up.

I'll see what Plusnet have to say tomorrow when they can hopefully prove or disprove my claims of really decent download speeds.

If the whole matter is due to a dodgy line/connection somewhere, it probably wouldn't solve that, but at least it might be like starting from fresh again.

I do apologise for being a bit of a P.I.T.A. with all this. I am trying to learn / understand as I go along, as well as get my speeds back again.
I might even get my life back again too. This silly issue seems to have taken over a little.

Mrs. Eagle would be pleased too, because I am supposed to be refurbishing the house, not messing about with modems, attenuation, SNR & so on.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 11, 2011, 08:25:29 PM
Hi All,

Just an update from my discussions with Plusnet today:-

There is no further progress >:(

What a crying shame I hear you say. He'll be around for a bit longer mithering us to death then.

I am now achieving 22 Mb downloads which is more than my originally estimated speed of 14.6 Mb, so tough!
That is apparently quite good for a line length of 5283 m. Does that length ring a bell Walter?
It is the figure that Plusnet quoted to me today, just to prove I have a long line & my expectations are too high

Plusnet have not capped my profile. It is currently being reported via Plusnet as 20 - 30 Mb, even though they say it is set at 37 Mb at their end.
When I mentioned that their own ticket system had previously reported it as 20 - 40 Mb, the response was that it does go up & down a bit. I fully accept that comment, but by 11 Mb or so?

Plusnet don't know or apparently care why my speeds have dropped. They were more than I should have been achieving anyway.
They are certainly a lot more than my previous 1 Mb via ADSL. I don't believe that to be a fair comparison from a technical support staff member.

I can request another engineers visit though, to do the tests that the "special" engineer should have done on Tuesday (when I waited at home all day for nobody to turn up), & again yesterday when the "special" engineer just replaced the BT modem & let me see the stats that we can't normally see because the BT modems are locked/disabled.

I may have to pay £144 + VAT for this visit though, if the engineer can't find a fault.
Well, if the engineers don't actually run the "right" tests, they obviously won't find any faults.

BT have not capped my profile either. My current 22-23 Mb speed is proof that I cannot achieve anything faster?

Do I still have an intermittent fault? I won't know until I lose connection or experince a crackly phone line again.
I suspect I still do have though as no "special" tests or work has been carried out on my line.
By "special", I mean at least the TDR test that the "special" engineer could have/should have carried out yesterday.
I had no idea at the time that the JDSU that he had in in hands could have at least carried out that test.

Has the new & improved version 2B BT modem "fixed" everything? I don't know, maybe (apart from my speeds).

Have I ever achieved decent speeds? Yes, as confirmed by Plusnet viewing my speed test in their ticket system.

Have BT ever proved that I have ever achieved decent speeds? Yes, as I confirmed in Plusnet's forum http://community.plus.net/forum/index.php/topic,96832.0.html
There it is razpag. The proof that I have searched for high & low!!!! I suspect you were beginning to think that I had never really synced at anything over 30 Mb.
It actually got better than that for a good few days. I didn't keep checking speeds then though, beacuse everying internet-wise was instant.

I might have to edit the very last sentence in that post, regarding the accuracy of Plusnet's availability checker.
What I meant at that time was at least it showed I could have FTTC, when the providers, BT, were saying it wasn't even available for me.

Can Plusnet examine their own logs of my decent connections as proof? No, they were auto deleted when BT reset my profile last week.

Do I really have a line length of 5283 m? Maybe, right back to the exchange (for phone purposes only)

What is my reported line length for FTTC broadband purposes? BT & Plusnet don't know. I estimate around 800 m or less from driving the route of the overhead cables that I can see to the cabinet (PCP 51) that BT have confirmed I am connected to.

What line length does my attenuation of 30.2 dB & SNR of 5.9 dB downstream suggest? Plusnet don't know. I can't ask BT as I'm not allowed to speak to them & I don't know how it is calculated for FTTC

How do BT & ISPs estimate likely speeds before signing up for FTTC? I don't know, Plusnet don't know except that "various" factors are taken into account. Maybe BT know, but are just keeping it a secret.

Do I need to consider the effect of interleaving now? Not at the moment. I have seen today's Plusnet report that confirms it is OFF for both uploads & downloads.

My neighbour, in the other half of the semi that I live in, does NOT have FTTC installed. Ah, good, what line length is reported for her ADSL connection? 5283 m. Well at least that proves that BT & ISPs are using irrelevant figures for estimating FTTC speeds, or does it? It is the length that Plusnet quoted to me today, so it must be, musn't it?

Is this whole thing an exact science? It would appear not at the moment, at least as far as those providing the service between them are concerned.

Are there many others in a similar position to me? I don't know, but I would imagine so, apart from those who live next to the FTTC cabinets.

Will this thing ever get resolved? Hopefully, given time.

Is it really the big deal that I have made it out to be? I think so, a loss of 10 - 12 Mb download speeds seems too significant to ignore.

Are download speeds guaranteed & stable. Absolutely not.

Why not? Too many variables. Even someone switching on a hair dryer or their flashing Christmas tree lights next door can have an effect.
Does my neighbour switch hers on a stupid o' clock in the morning & cause my disconnections? I have never heard the hairdryer & it's the middle of summer FGS.

Is this a waste of time? I hope not for my personal case & I hope that once I have all the answers it may be of some help for others in similar situations.

Is there a reliable database of FTTC real user achievable speeds & connection statistics? I have not managed to find one. I might start one off with a link to Kitz.co.uk.
Obtaining connection stats is probably the biggest hurdle, unless you collar the friendly engineer when he installs FTTC, or turns up to "repair" your faults.

Why are the BT modems disabled for obtaining connection stats. I don't know. Maybe it is just to make it too hard to prove you have a sub-standard connection?

Thanks all for tolerating this ranting & rambling from me (for now).

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 11, 2011, 09:36:32 PM
Mr Eagle -- My answer to one of your earlier questions is that interleaving only affects the speed of data throughput and not the line sync speed.

My comment on your situation, having re-read everything you have written, is that you have an intermittent fault on the copper pair, which manifests itself as a crackly line. Your voice line, thus, is not operating within specification and your telephony provider is required to correct the fault. To do so, they must employ a representative of the owner of the infrastructure to trace the fault and then fix it.

Your telephony provider = the company you pay for your telephone calls.
The owner of the infrastructure = OpenReach.

Once the underlying copper pair fault is correctly fixed, then we should review your broadband (FTTC) speed.

Finally, have you made direct contact with Bob Pullen of PlusNet?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 11, 2011, 10:28:21 PM

Finally, have you made direct contact with Bob Pullen of PlusNet?


Hi burakkucat,

I have tried to contact Bob via Plusnet's service.customer-feedback usenet group (subject F.A.O Bob Pullen - Ticket #44208926) a few days ago as many others appear to achieve success via this route.

Unfortunately I have not received any response from him yet.

BTW, I pay Plusnet for both my phone & broadband services since my switch to FTTC.
Prior to that, I paid BT for my telephone & Plusnet for my broadband.

I have been a Plusnet customer in its various guises (Free-Online, Force9, Plusnet) for many years & have previously been very satisfied with their customer service & fault resolution processes.

Indeed, I am not actually complaining as such now (although it may be coming across that I am). I am just becoming a little more frustrated each day with responses that don't really appear to address the underlying issues.

I am more than willing to accept that FTTC is a reasonably new technology that is not fully understood at this time, even by those who deliver the service i.e. BT & ISPs between them, as long as they don't give up and/or hide behind inaccurate & very conservative speed estimates.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 11, 2011, 11:20:55 PM
Hi
quote Signal to Noise Ratio also affects line speed. A high SNR = good, a low SNR = bad.

Just to clarify

SNR  Signal to Noise Ratio  the higher the better ,that is like if 2 people are talking (that is the signal) then the lower the background noise the better
.
But There is what is known as  SNR Margin normally 6db is recognised as the  minimum amount of Spare SNR between the level of line noise and the transmitted signal(normal target SNR) . In the above analogy would be at what point would background noise begin to affect the 2 people talking .So immediately after synching you would expect to have a margin of about  6db.
Here HIGH SNR margin is not good .
Normally the Higher the SNR margin the lower the Synch Rate .
High Target SNR
Any connection is monitored and its quality is measured .Where a line is found to be unstable then the  target SNR nominally 6db is increased ,this is in 3db steps up to a maximum of 15db.

on 8max this can cost about  800kBps per 3db above the nominal 6db. Depending on Bit allocation .The more tones used then the greater the effect of increased SNR margin.(about 4Kbps/db/tone) .

After  a connection is made then the SNR margin invariably changes with time . Gradual changes are normal during any 24hour cycle . sudden increases indicate abnormal noise conditions .

Funnily enough this is where Higher snr margin indicates an improving line condition whereas a drop in SNR margin indicates a worsening line condition
Regards Jeff


 


 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 11, 2011, 11:38:49 PM
@ jeffbb

Thanks for that info.

I see you are currently experiencing your own SNR / SNRM issues that have affected your sync rate in quite a big way:-

http://forum.kitz.co.uk/index.php/topic,9752.0.html

Paul
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 12, 2011, 08:17:40 PM
Quick Update

Modem No. 3 (version 2B) has surprisingly not "fixed" everything for me.

Suffered just 1 disconnection today, the only one since Wednesday, but the DLM still robbed me of 6 Mbps or so.

Downloads now back down to around 17 Mbps.

Good news: One of Plusnet's staff appears to be taking a slight interest. It is the same guy that opened my original ticket back on 5th July.

http://community.plus.net/forum/index.php/topic,97734.0.html if anyone has the slightest interest. My bit starts quite a way down the post.

The ping looks O.K. though, not that it really matters to me as I don't play online games.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 12, 2011, 09:20:18 PM
A Quick Grumble

Oi, baldy / Mr Eagle / Paul -- until the underlying intermittent problem with the POTS has been fixed by OR, there is absolutely no point in pursuing any broadband speed issue. :no:

Please, for your own sanity, ask PlusNet to arrange for an OR engineering visit to trace and fix the intermittent POTS problem, which is possibly a HR joint. TDR will be required to identify the location. ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 13, 2011, 08:54:08 AM
@ Paul,

Given that we're in "needle in a haystack" mode it might just be worth asking the next visiting engineer to check that your pair have been totally isolated from the (probably) redundant overhead line protection unit.

Almost certainly the "Fuses" have been removed but sometimes the pair teed off the through line are left connected leaving a twisted pair wire "aerial" in circuit. Even though this is only a remote possibility of noise it's as well to remove every factor which might affect the line's reliability.

For those interested here's an article on the subject.

http://www.epanorama.net/documents/surge/telesurge.html

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 13, 2011, 12:53:53 PM
A Quick Grumble

Please, for your own sanity, ask PlusNet to arrange for an OR engineering visit to trace and fix the intermittent POTS problem, which is possibly a HR joint. TDR will be required to identify the location. ::)


Oi, burakkucat, you big Pussy :)

Plusnet have offered me that option.............at a cost of £144 + VAT each time the engineer does not track down the "intermittent fault".

This option could prove rather costly for me, unless, by chance the engineer found the fault on the first visit.
With these BT modems, there are no means to monitor line stats/quality etc. so, determining when the best time to organise a visit that "might" find a fault is more or less impossible.

Reaction times following disconnections is obviously also a problem, unless BT have an 'A' Team on standby.
I understand, & fully accept that BT must have much higher priorities than dealing with issues such as this.

Thanks (meant genuinely) for your concern regarding my sanity though. I suspect I am driving others a bit mad too.
If I'm not careful, this could push me over the edge.

I'm also in trouble from Mrs. Baldy Eagle for messing about with this when I should be carrying on with refurbishing the house. I only started it 8 years ago.

Now, if anyone with the right testing equipment & skills happens to stumble across this message & is within striking distance of Oldham & fancies a bit of the folding stuff being forced into their hands, by all means, send me a PM to arrange it ;)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: bobpullen on August 15, 2011, 06:26:01 PM

Finally, have you made direct contact with Bob Pullen of PlusNet?


Hi burakkucat,

I have tried to contact Bob via Plusnet's service.customer-feedback usenet group (subject F.A.O Bob Pullen - Ticket #44208926) a few days ago as many others appear to achieve success via this route.

Unfortunately I have not received any response from him yet.

Just seen said post today. Apologies for taking so long to pick it up, my workstack's been a little hectic of late! I have responded but if I'm honest the reply is nowhere near reasoned enough based on all of the information this particular thread contains!

BTW, I pay Plusnet for both my phone & broadband services since my switch to FTTC.
Prior to that, I paid BT for my telephone & Plusnet for my broadband.

I'm guilty of having only skim read the 7 pages that make up this thread, but is there or isn't there any noticeable degradation of your voice service? If there is then that's one avenue we're yet to explore from what I can gather?

I am more than willing to accept that FTTC is a reasonably new technology that is not fully understood at this time, even by those who deliver the service i.e. BT & ISPs between them, as long as they don't give up and/or hide behind inaccurate & very conservative speed estimates.

I recognise that you may well have been synchronising above your current rate at one point, but I can kind of accept the reasoning from some of our help-desk folk. Whilst admittedly it's conservative, you're still currently synchronising 9Mbps above the estimate returned by a BT Wholesale availability check, and that's a pretty significant amount.

If you do wish to go down the repeat engineer route, then by all means let me know and I'll see if I can get one of our seasoned faults bods on the case. I'll also do whatever I can to avoid you suffering the wrath of any Openreach appointing fees. As mentioned above though, if there's any defect with your voice service then I think that's the most favourable route to take.

Best regards,
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 15, 2011, 06:50:43 PM
Hello Bob -- Thank you for looking in on this thread.

Just to save some time, please have another look at point (2), post no. 6, on page one. Your customer, Mr Eagle, suffers from an intermittent voice fault which manifests itself as a crackly line. When tested at the most basic level, the POTS pair return as LTOK. Hence more advanced testing -- TDR -- will be necessary to locate the suspected HR joint. ;)

If you then go to page five and find the report of the last OR engineer's visit (the relevant posts are dated August 10th) all he did was to swap out the HG612 modem, no TDR, no tracing of the (suspected) HR joint, etc. :(

So that fault still persists in the copper pair and if it is on the D-side, it will also be having an effect on the VDSL2 signal -- thus degrading the broadband service. :doh:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 16, 2011, 01:04:57 AM
Just seen said post today. Apologies for taking so long to pick it up, my workstack's been a little hectic of late! I have responded but if I'm honest the reply is nowhere near reasoned enough based on all of the information this particular thread contains!

I'm guilty of having only skim read the 7 pages that make up this thread, but is there or isn't there any noticeable degradation of your voice service? If there is then that's one avenue we're yet to explore from what I can gather?

I recognise that you may well have been synchronising above your current rate at one point, but I can kind of accept the reasoning from some of our help-desk folk. Whilst admittedly it's conservative, you're still currently synchronising 9Mbps above the estimate returned by a BT Wholesale availability check, and that's a pretty significant amount.

If you do wish to go down the repeat engineer route, then by all means let me know and I'll see if I can get one of our seasoned faults bods on the case. I'll also do whatever I can to avoid you suffering the wrath of any Openreach appointing fees. As mentioned above though, if there's any defect with your voice service then I think that's the most favourable route to take.

Best regards,

@ bobpullen

Hi Bob,

Thanks for responding, both here & in p.s.customer-feedback
I'll try to summarise here for now, although you do also have the very long Plusnet ticket No. including screenshots & Plusnet reports to wade through when you get the time.

FTTC was installed 24th June. The engineer repositioned the master socket from upstairs, to downstairs next to my desk, using my own existing good quality "data" cable. After a couple of trips to the cabinet & back, the engineer told me I had a speed of around 35 Mb, which was about right for my distance from the FTTC cabinet. He also told me not to expect the full 40 Mb as it was just a bit too far away.

Right up to the first issue 4th July, everything was fantastic, with download speeds consistently around 32-33 Mb.

4th July, the first really warm day since FTTC was installed, & after a few hours use, the BT modem could not maintain a connection.
I had read about overheating modems & phoned Plusnet to report the matter.
While on hold, I installed a desk fan, pointed directly at the BT modem, although the modem only felt warm, not hot.
Following instructions from the Plusnet agent, we tried a few things, including plugging my ethernet cable directly into the modem & setting up a new connection.
Nothing we did made any difference, so I plugged the ethernet cable back into the router & the router cable back into the modem.
Just as we were about to conclude the phone call with the ticket being updated as a modem fault, the BT modem reconnected. After a few speed tests etc, everything looked stable again, so we left it, as I thought, that the modem would be replaced in due course.

A few days later, I noticed my download speeds had dropped by around 5 Mb. I was advised to wait for 10 days or so, & that if the connection appeared stable, I should regain the previous decent download speeds.

21st July, I enquired if the "defective" modem needed replacing as my IP Profile & download speeds had not improved.

22nd July, completely lost both broadband & telephone services.

26th July, 3 engineers took a few hours to locate the fault that was "somewhere on the external line" & restore broadband & telephone services, informing my wife who was at home at the time that "someone else" living nearby had also suffered a similar issue.
Download speeds had now dropped to around 16 Mb & upload speeds had dropped to around 0.6 Mb.

2nd August, download speeds had gradually dropped to around 8 Mb, with uploads still at around 0.67 Mb.

4th August, the BT Modem was replaced & BT reset my profile, but only to 24 mb, saying that was the maximum that my line could achieve due to the distance from the cabinet. The engineer queried this with BT as he could see my printed test results that clearly showed download speeds of 32-33 Mb.
Plusnet also informed me that my original estimated speeds were 14.6 Mb & that as my line was currently performing over an acceptable rate for the length of my line there was nothing they could do to push the matter.
My download speeds were then around 22 Mb, some 10-11 Mb less than when FTTC was installed.

5th August, the modem lost connection & would not reconnect, so I phoned Plusnet to report the matter. At that time the phone line was very crackly. While I was on hold, the modem reconnected & the phone went quiet again.
I asked the Plusnet agent to add this to my existing ticket to keep an ongoing record of the various issues I was experiencing.
I subsequently discovered he had actually created & closed another ticket (#45200538).
I registered with Kitz forums & started asking questions in this thread

8th August, Plusnet accept that my connection is still dropping on a regular basis & confirm that once it is stable again the low speed issues will be looked into again.
Following an telephone discussion, an engineer's appointment was arranged for 9th August to investigate intermittent line issues such as high resistance etc. that would require "special" tests

9th August, engineer did not arrive. I was informed that BT had carried out some basic remote tests & confirmed a visit was required, but had been unable to book it.
A visit was arranged for 10th August to carry out the "special" tests.

10th August, engineer arrived & after simply confirming my line speed was more that the 15 Mb that BT have to guarantee, replaced the 6 day old modem with a new one. The new modem (No. 3) is a version 2B, supposedly improved & tested.
The engineer showed no interest at all in the previous issues leading up to his visit.
The only comment he made was that I should have reported the crackly phone line. When I told him that I had reported it to Plusnet, he just said that nobody at BT had made him aware of it.
When asked if he would be carrying out the "special" tests (TDR etc.) to look for high resistance type faults, he said he wouldn't as he had been sent to just confirm the speed was more than 15 Mb & replace the modem.
He either refused to tell me, or just didn't know how to confirm my line length when I asked him.
He did also mention that he didn't really understand these matters anyway.
By this time, I was aware that BT were reporting my line FTTC length as 5283m & I suspected this was partly the reason for the very low originally estimated speed of 14.6 Mb.

11th August, I discussed the whole matter with a Plusnet agent who confirmed that if another engineer visit was requested, I may well be charged £144 + VAT if he could not locate a fault, intermittent or otherwise.
This agent also quoted my reported line length of 5283m, hence the low estimated speeds.

As I live only around 600m from the FTTC cabinet, this reported 5283m is completeley irrelevant.
Indeed, it has been proven that my line could maintain download speeds of 32-33Mb (until the "issues" started).
I have however been told that records of these achievable & reliable connection speeds were deleted when BT reset my profile to around 24 Mb. Is this really the case?

Since the issues started I have lost connection many times, I completely lost the broadband & phone services for a number of days & am now suffering via reduced connection & download speeds. You comment that I am currently achieving 9 Mb more than the estimated speeds which is a significant amount.
From my point of view, I am currently able to download at around 12 Mb LESS than my connection was originally achieving. This is an even more significant amount.
Nobody at Plusnet or BT is able to explain what the estimated speed was based upon, other than I have a reported long line.
(Please also see or discuss the dialogue I have recently had with Alex R in the Plusnet Community forum).
Incidentally, Alex was the first person to pick up the Plusnet ticket regarding this matter.

My connection currently appears stable & if this is to remain so, I may regain my lost speeds given time.

I cannot honestly claim that I currently have a degraded phone service to help speed this along.
However, I am not aware that any work has been carried out on it since I reported it 5th August, so maybe the fault report is still live?

However, the consensus of opinion from the knowledgeable & "hands on" experienced members of this forum is that I am suffering from an intermittent line fault, that combined with what appear to be high attenuation levels, would suggest a high resistance issue.

As this was discussed with, but not tested by the 2nd engineer who just replaced the modem, I do not feel that I should be now charged to have the tests carried out that I believed had been previously arranged.

We further believe that the original speed estimate of 14.6 Mb is not valid & should no longer be referred to, as from what we can gather, it has been based upon BT's inaccurate line length data, rather than the actual line length between the FTTC cabinet & my home.

Apart from the ongoing potential line/connection issues, it appears to me that there has been a breakdown of communication between Plusnet & BT, & an admitted lack of understanding of the whole FTTC technology.

My frustration is that it has taken a very long time (since 4th July), with little or no tangible progress with this matter.

I am confident that this matter will be resolved at some stage in the not too distant future, providing the "right" people, with the "right" knowledge & skills are dealing with it.

I would have much preferred to have been able to resolve this matter in a private manner, but had no choice but to request help & advice in a public forum.

You do have my contact details so perhaps you could give me a call to discuss a way forward with this.

Finally, to conclude, I would comment that I have been a loyal Plusnet customer, via Free-Online, F9, & Plusnet for many years & as your records would demonstrate, I do not make a habit of complaining.
I am not actually complaining now, rather I am merely stating fact & requesting some assistance in resolving an admittedly tricky problem, that is exacerbated simply by not being able to monitor my own connection statistics due to the lack of user access to the BT modem.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 16, 2011, 08:42:23 AM
Very well said Paul - even if it is at some length !
(Perhaps Kitz should publish the records for the shortest and longest posts on her excellent website !)

There are clearly longer term issues here. Surely we must try to improve the "customer experience" and reduce PlusNet's (and all ISP's) costs / fault repair process times. Playing these sorts of commercial-political games must be very harmful and exceedingly wasteful.

At a practical level, unless RP can suggest a better solution, it would appear that tests with recorded results should be conducted with the E side line temporarily disconnected ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 16, 2011, 01:42:52 PM
Just a thought..........

Is anyone aware of a low cost "device", readily available to end users, that could be connected & left inline between the master socket & the BT modem, purely for the purpose of obtaining connection statistics such as Attenuation, SNR, Max Rate, Actual Rate, Line Length?

I have looked around the internet, but I will admit that I wasn't quite sure exactly what search words to use.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 16, 2011, 05:40:50 PM
@Mr Eagle -- I have been thinking about exactly that situation but can not come up with an answer.

Of course, if £1600 is low enough on your scale, one could purchase a refurbished JDSU HST-3000 (plus the correct module) on eBay. However, that would not be something that could be placed in series, between the HG612 and the NTE5/A. :no:

If I was in that situation, I would be tempted to purchase my own VDSL modem/router and use it in place of the OR supplied device. Walter has started a thread concerning suitable devices . . . now where is it? Ah, here it is (http://forum.kitz.co.uk/index.php/topic,9707.0.html). ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 16, 2011, 06:43:24 PM
Very well said Paul - even if it is at some length !
(Perhaps Kitz should publish the records for the shortest and longest posts on her excellent website !)

There are clearly longer term issues here. Surely we must try to improve the "customer experience" and reduce PlusNet's (and all ISP's) costs / fault repair process times. Playing these sorts of commercial-political games must be very harmful and exceedingly wasteful.

At a practical level, unless RP can suggest a better solution, it would appear that tests with recorded results should be conducted with the E side line temporarily disconnected ?

Kind regards,
Walter

I agree, extremely well put Paul (especially the parry regarding you achieving 9 Meg over the 15 Meg guarantee), and I believe it had to be as long as it is, in order to put factual evidence over stating what has been done and at what time.

Now then Walter, I have to say that's a good idea about testing with the E-side temporarily cut away in the PCP. That could then only give readings and stats regarding the DSL frequency. Great point.

The other question about some kind of in-line device for monitoring purposes ?? I wouldn't expect there to be such a thing other than the actual Hub/Router/Modem ??
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 16, 2011, 08:42:58 PM

I agree, extremely well put Paul (especially the parry regarding you achieving 9 Meg over the 15 Meg guarantee), and I believe it had to be as long as it is, in order to put factual evidence over stating what has been done and at what time.

Now then Walter, I have to say that's a good idea about testing with the E-side temporarily cut away in the PCP. That could then only give readings and stats regarding the DSL frequency. Great point.

The other question about some kind of in-line device for monitoring purposes ?? I wouldn't expect there to be such a thing other than the actual Hub/Router/Modem ??


Cheers razpag,

I'm not trying to score points here. I just want my previous decent speeds back again.

The hardest part seems to be able to convince the service providers that my line really is "sometimes" actually capable of delivering, & that there may actually be a reportable fault with it currently.
 
Between them, it appears they both believe my line is actually very long & not able to deliver anything more than the estimated speed of 14.6 Mb. Additionally, if by some fluke I do ever achieve more than the estimated speeds, I should just consider it a temporary bonus.

I still can't work out whether the previous "defective" modems, or the potential intermittent line quality have caused the massive reduction in speeds, especially as there is currently no way to monitor either.

FTTC's DLM appears to be incredibly keen to reduce speeds in order to provide stable connections, but nowhere as keen to reinstate speeds following a spell of stable connection.

Touch wood, the current modem, Echolife HG612 version 2B, appears to be holding its own, or is it just that my line has settled down for a while? No doubt time will tell.

Even if it is possible to arrange another engineer's visit at no cost to me, I'm not too sure how to persuade him/her to carry out the "relevant & necessary" checks & tests e.g. temporarily cutting away the E side, especially when I recall that the latest Special Faults engineer actually told me he didn't really understand FTTC anyway.

In time, I'm sure we will gradually build up the same level of knowledge regarding FTTC that is available for ADSL, based in part upon real life experiences.
e.g. If I gave my ADSL attenuation & SNR values to anyone who has any interest at all, they could probably work out what sort of speeds I should expect, what the figures mean in terms of distance from the cabinet etc. within a few seconds, or at least be able to confirm a likely reportable "fault" with some certainty.

Nobody currently appears to be able to do that. Even my ISP admits it doesn't know how to work any of it out.

I very recently posed a couple of queries to them:-

Q.
I realise the 5283m is the distance from the exchange & not the cabinet, which is why I find it strange that it is still being reported by BT & Plusnet.
However, via FTTC, this is a meaningless distance to quote.

A.
At the moment we don't have a system to check this.

Q.
                              UP                    DOWN                 
Actual Rate             1996K                22648K
Max Rate                5212K                22662K
Capacity                   38%                  100%
SNR                      12.9 dB                 5.9 dB
Line Atten              52.9 dB               30.2 dB

As my Line Attenuation for downstream (30.2 dB), as reported by the last engineer's JDSU, appears quite high for the relevant FTTC distance, it would be really more helpful if FTTC distances were quoted in order for users to "have a feel" for their line conditions & expectations, possibly highlighting potential problem areas.

My line Attenuation for upstream also appears really high at 52.9dB, & in fact appears to be the complete opposite to ADSL attenuations.
Could this signify a problem area?

Is this normal for FTTC?

A.
Our line testers don't show any figures for Attenuation on FTTC or FTTP so it's hard to say what normal figures are.

If these queries had been in connection with ADSL, clear, concise, & quite accurate responses would have been immediately provided, along with relevant advice.

If the providers don't yet know the answers, as users are we supposed to just grin & bear it, just thinking it is what it is?

razpag, do you know if there is any way to obtain my original line/connection stats from when FTTC was first installed? i.e. do BT keep an installation record?
This would be really useful information that would at least allow me to compare them against my latest stats.

On a positive note for all, I really do intend to keep any of my future posts much shorter than the recent ones.
If the answers were already out there, I wouldn't have needed to ask so many questions.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 16, 2011, 09:01:04 PM

Of course, if £1600 is low enough on your scale, one could purchase a refurbished JDSU HST-3000 (plus the correct module) on eBay. However, that would not be something that could be placed in series, between the HG612 and the NTE5/A. :no:

If I was in that situation, I would be tempted to purchase my own VDSL modem/router and use it in place of the OR supplied device. Walter has started a thread concerning suitable devices . . . now where is it? Ah, here it is (http://forum.kitz.co.uk/index.php/topic,9707.0.html). ;)

@ b*cat,

In principle I would prefer not to have to pay for an "unofficial" modem, just because the BT modem cannot be monitored.
It would almost be like having to buy a different car just to get a petrol guage.

However, a slightly cheaper one than £1600 would at least give me some indication as to how my line is actually performing i.e. showing further deterioration, or hopefully gradual improvement.

The usual speed tests are O.K, but they actually prove nothing.

Of course, I would never be able to quote any results to prove an issue, as it would also prove that I had been using "unofficial" equipment & no doubt relinquish BT of their already questionable responsibilities.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 16, 2011, 09:05:02 PM
Slightly off topic:

I have just noticed we are now on page 8.

Size isn't everything, but it's always nice to know you have a big one....................forum thread that is :lol:

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 17, 2011, 11:26:24 AM
UPDATE 17-08-2011

WHAT A RESULT!!!!!!!!

Modem just disconnected.

I picked the phone up to check. IT WAS CRACKLING. Brilliant I thought!

As I was looking for the Plusnet phone No. my mobile phone rang.
It was Alex from Plusnet to say he had been doing some remote line tests etc. & that was probably the cause of the disconnection.

I put the mobile's microphone to the landline phone's earpiece for Alex to hear the crackling noise.
I'm not sure whether he heard it or not.

However, we had a really constructive chat & the result is that a BT engineer's visit is now arranged for monday morning to definitely look into the line issues by at the very least running TDR & HR tests.

Alex has also read this Kitz thread so he is fully aware of the issues & will be keeping a personal eye on progress.

Things really are looking up.

Hopefully, my next (long) post will be to confirm how everything is sorted.

I will also keep you posted with feedback (short messages) in the meantime.

Modem reconnected. Speeds down again, but I can live with this for now as I now know action is in hand.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on August 17, 2011, 11:27:31 AM
I'll check in with you on Monday to discuss the outcome of the telephone engineer visit.  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 17, 2011, 11:34:20 AM

I'll check in with you on Monday to discuss the outcome of the telephone engineer visit.  ;)


Thanks Alex.

FYI, This really is the best forum I've seen.
The members on here only really deal with facts & well informed real-life "hands on" experience, unlike some other forums that I won't name that really are full of BS & falsehoods (not Plusnet's by the way).

EDIT:-

Also thanks for not just agreeing to, but actually suggesting we keep the feedback going via this public forum.
Plusnet cant really be any more open & transparent than that.

Now, where is it that I apply for my completely free broadband & phone services? (hint)  ;)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 17, 2011, 06:16:26 PM
Now then .......... just to add to the 'feelgood factor' the latest additions to this thread have given, I have a wee bit of info I personally found out today.

This morning out of the blue, I received a call from my 'Control' asking if I'd help another patch out with a FTTC Managed Install task. As previously mooted, these tasks now go to the ex-servicemen and apprentices that BTOR have drafted in. Obviously, workstacks must have been to high for them to cope, so off I went.

With burning issues from this thread on my mind, I couldn't wait to get to the damned Fibre Cab !! Anyhows, as again mooted previously, the first test we do is to see if we can gain synch direct from the Fibre Cab (approx 10mtrs away) which I did at 40 Meg DS and 10 Meg US, with an attenuation of 1.5dB. Went through the other usual stuff and then off to the premises, which is approx 500/600 mtrs away (I will get the exact distance later when I get time to add up the cable lengths). When testing at the NTE5 with my JDSU, I had an attenuation of 13.5dB and an US of the full 10 Meg and a DS of 39.9 Meg.

Therefore, my conclusion from this one and only hands-on test that I've done since this thread started, is that the attenuated figure taken from the NTE5 VDSL frontplate, with a JDSU/EXXFO tester, only reports the line length from the Cab to premises, NOT the line length from the Exchange. I thought this may be the case, but wasn't 100% sure until today.

So, Baldy  ;D, we have three issues. 1) Are your attenuated stats mentioned on here, taken from the NTE5 VDSL frontplate, or from the Hub V3 ???  2) Are you positively sure you are only 0.5Miles from the Fibre Cab ?? 3) If you are, then your attenuated reading is way too high unless you are fed over wet string.

Going from what you said above only today, I suspect you still have that HR fault lurking, especially as you could still hear a 'crackling' noise ?? This is what is hopefully pushing your attenuation through the roof. I say hopefully, as it means if it is a HR, it can be faulted and fixed.

Please, please, please ask the engineer to use his TDR function (affectionately called a 'mole'). If the HR is miniscule, it still won't show. If that's the case, ask them to explain how your line is so highly attenuated over such a (reported) short distance ?? If they look at you blankly, don't be surprised (as the training we get is very, very basic), just ask them if they can ring a colleague who will know about attenuation and get them to what we call 'Assist' on the task.

Sounds like you may have turned a corner at last here Paul. Best of luck bud. ;) ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 17, 2011, 07:47:14 PM
What a co-incidence, Mr Pag. Although it is not the same as having personal experience (and how, one may ask, can a black felis domesticus have the experience of a OR employee?), it is very useful to read your first hand experience.

Did you, perchance, think of taking a set of photographs at each stage so that they could be added to a new FTTC section on Kitz' website? If not, would it be possible to do so at a later install that you attend?

Deviating slightly, b*cat is still keeping his critical eyes open for a means to get hold of a Huawei HG612, as modified for supply by OR.

Deviating a little more, with regards to obtaining the usual statistics from the OR modem, asbokid (http://forum.kitz.co.uk/index.php?action=profile;u=5879) has managed to do so. I attach to this post a series of screen-shots he has obtained (cropped by me, so that they may be attached). :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 17, 2011, 07:57:46 PM
Hi B*Cat

Unfortunately, no I didn't take any snap-shots. TBH, time is precious when working for OR these days. Photo's and the like, just don't occupy ones thoughts when you know there's up to 4 individuals monitoring your progress. >:(

Regarding the Modem mate, E-bay's yer best bet I would guess. Apart from the fact that, all stores allocated to an individual are itemised and billed to that individuals OUC (Manager in other words), It would be foolish of me to risk my livelihood (sp) over a Modem. Jobs are precious these days, and apart from the micro-managing and i-POP, I like mine. ;D ;D   
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 17, 2011, 08:22:54 PM
Quote
Unfortunately, no I didn't take any snap-shots. TBH, time is precious when working for OR these days. Photo's and the like, just don't occupy ones thoughts when you know there's up to 4 individuals monitoring your progress. >:(

That's unfortunate, as they would prove to be a very useful addition to this web-site. Obviously, though, the requirements of your job comes first.

Quote
Regarding the Modem mate, E-bay's yer best bet I would guess. Apart from the fact that, all stores allocated to an individual are itemised and billed to that individuals OUC (Manager in other words), It would be foolish of me to risk my livelihood (sp) over a Modem. Jobs are precious these days, and apart from the micro-managing and i-POP, I like mine. ;D ;D

For the record -- i.e. for any "outsider" who may read this thread -- b*cat recognises that it would be absolutely incorrect for Mr Pag (or for any other OR employee in the "front line") to pass his employer's stock on to a third party (and wishes it to be noted that no such request has been made). :no:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 17, 2011, 10:37:46 PM

Therefore, my conclusion from this one and only hands-on test that I've done since this thread started, is that the attenuated figure taken from the NTE5 VDSL frontplate, with a JDSU/EXXFO tester, only reports the line length from the Cab to premises, NOT the line length from the Exchange. I thought this may be the case, but wasn't 100% sure until today.

So, Baldy  ;D, we have three issues. 1) Are your attenuated stats mentioned on here, taken from the NTE5 VDSL frontplate, or from the Hub V3 ???  2) Are you positively sure you are only 0.5Miles from the Fibre Cab ?? 3) If you are, then your attenuated reading is way too high unless you are fed over wet string.

Going from what you said above only today, I suspect you still have that HR fault lurking, especially as you could still hear a 'crackling' noise ?? This is what is hopefully pushing your attenuation through the roof. I say hopefully, as it means if it is a HR, it can be faulted and fixed.

Please, please, please ask the engineer to use his TDR function (affectionately called a 'mole'). If the HR is miniscule, it still won't show. If that's the case, ask them to explain how your line is so highly attenuated over such a (reported) short distance ?? If they look at you blankly, don't be surprised (as the training we get is very, very basic), just ask them if they can ring a colleague who will know about attenuation and get them to what we call 'Assist' on the task.

Sounds like you may have turned a corner at last here Paul. Best of luck bud. ;) ;D

@ razpag

Thanks for the info - distances, attenuation etc.

1) The stats that I have listed are indeed taken directly from the faceplate. I am not aware they can be taken from anywhere else in the EU's premises.
What is a Hub v 3? Is it the BT Home Hub? I don't have one of these. I have a Netgear router plugged into the Echolife HG612 v 2B modem.

2) By road I am near as damn it 0.4 miles from the PCP. I have driven the "probable" route. Due to the lack of other roads &  DPs in my area there is only 1 other "possible" route. That route is unlikely though as it would take me back toward the Oldham exchange for a few hundred yards or so before doubling back toward my house.
The overhead cable goes from my house on a slight detour before heading toward the PCP, so 0.5 miles is probably about right.

3) The wet string is quite possible when considering my attenuation, dropped connections etc. It was warm & sunny when I first lost connection today. Maybe the string dried out & we just have a simple "dry joint" to track down?

I had a further 3 disconnections around noon today, resulting in my profile dropping back down from 23 Mb to 15 Mb again.
In a strange way, that is good news as it clearly points to a "fault".
I do hope the "fault" is still present on Monday. As we all know it appears to be of an "intermittent" nature.

THis is what Alex added to my Plusnet ticket:-
"PSTN engineer booked to check for HR fault on D-side which may be affecting broadband
speed",
But don't worry. I have already been rehearsing what to say when the engineer turns up.
Alex mentioned the Hawk for TDR testing, but didn't you say these have been regretfully replaced by the JDSU now.

On a "good" line, what sort of line length would you expect for my reported attenuation of 30.2 dB downstream & 52.9 dB upstream & is there usually such a difference between downstream & upstream attenuations?

If you haven't specifically noted JDSU attenuation readings to date, I have a funny feeling you may well look at them a little more closely from now on.

If you were able to pass on such actual values & line length comparisons to us (me in particular at the moment) A pretty useful record of statistics could be built up that may assist us all to gain a much better understanding of FTTC matters.

Fingers (& everything else) crossed for Monday then.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 18, 2011, 12:54:35 AM

Deviating a little more, with regards to obtaining the usual statistics from the OR modem, asbokid (http://forum.kitz.co.uk/index.php?action=profile;u=5879) has managed to do so. I attach to this post a series of screen-shots he has obtained (cropped by me, so that they may be attached). :)


@ b*cat

I have seen those screenshots before. It's just a shame it is so difficult to obtain them.

Just imagine, if I could have obtained that basic level of info from my BT modem, I could have saved us all an awful lot of time.

I appeciate that SNR values fluctuate for many reasons, but I take it that attenuation on a "good" line should remain reasonably static.

If I had been able to monitor the attenuation readings for my own connection, I would have been immediately alerted to a problem.

e.g. if my actual line length is roughly the same as the example that razpag quoted today, I should expect an attenuation of around 13.5 dB, or maybe a little higher as I do know that my line takes a slight detour.
How I wish I could get my hands on the attenuation value from the day that FTTC was first installed & compare it against the last checked value.

As my attenuation, when last checked by the BT engineer, was 30.2 dB, a "problem" is immediately suspected.
As attenuation is a logarithmic value, a reading of 30.2 dB would suggest quite a big problem for my likely actual line length.

Had I been able to monitor the attenuation for myself I would surely have detected large fluctuations, the value being possibly a lot lower on the good days when I didn't drop connection, & possibly sky-high today when I had 4 disconnections & a crackly phone line.

With this basic information I could have passed a log of readings to Plusnet, who in turn could have passed them to BT as evidence of a "fault", possibly of an intermittent nature.

It may just be that my issue(s) could have been resolved back in July.

When I think back, I will have had FTTC for 8 weeks by this Friday.
The first 2 weeks were absolutely brilliant & the other 6 weeks not so brilliant at all.

As I have been unable to monitor line conditions myself, as & when connections and/or speeds have dropped, I have needed to rely on others, who appear to have not carried out the relevant tests to date, resulting each time in a Line Tests O.K. response.

Hopefully, & I believe partly due to our persistence & well informed discussions on this forum with regard to this matter, everything will be permanently fixed on Monday.

I do accept that a little knowledge can be very dangerous in the wrong hands, but the decision to deny everyone the facility of at least monitoring their own connection does seem to be a little strange.

Having no data whatsoever as to what may be causing dramatic & sometimes quite sudden speed reductions & disconnections makes it incredibly difficult for users to prove they have a problem in the first place, & incredibly easy for BT to "fob off" the less persistent user.

I do hope that you can somehow get your hands on a modem to experiment with, ideally resulting in an "approved" firmware update that we can all easily install, thus allowing us to see the basic stuff that we all feel we should be able to see.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 18, 2011, 02:13:30 AM
Mr Eagle,

I fully understand and appreciate what you have written.

With regards to your line attenuation -- copied photographically, as we appreciate, from the engineer's JDSU -- I still think there is something wrong with the upstream & downstream values. Currently, as I have no experience of VDSL (perhaps I should go and visit my neighbour, who has BT Infinity installed, clutching my laptop, dodahs & whatsits and ask if I could have a "fiddle"), I think it should be possible to obtain a general "feeling" by extrapolating from ADSL --> ADSL2 --> ADSL2+ --> VDSL2 (which is used "copper-side", cabinet <--> EU, for FTTC). So at ADSL frequencies, it has been observed that the upstream attenuation is somewhere between 50 - 60% of the downstream attenuation. What were the values reported by the JDSU? Upstream 52.9 dB and downstream 30.2 dB. Eh??

(1) Let's assume the values have been swapped over due to a JDSU software bug. So we consider 52.9 dB downstream and 30.2 dB upstream. A quick calculation gives U/S to be ~57% of D/S. It fits. But the overall values are too high for your D-side copper length.

(2) Let's assume the JDSU has reported them correctly. With D/S at 30.2 dB, I would expect an U/S of ~16.6 dB. What could cause such an asymmetric distortion of attenuation v frequency? A corroded joint, acting as a diode, perhaps?

Hmm :hmm: Interesting but, as Mr Pag will say, web-based fault-finding is no substitute for the real thing.

b*cat looks at the time -- gone 0212 hours BST -- so he waves a paw in acknowledgement and pads of to find a warm, sleepy spot (his bed).
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 18, 2011, 07:19:17 AM
Will have to reply to all later as off to work but a copy of the PM sent to BE for others to mull over. More-so Plusnet.

Very quick reply as off to work in a minute. I'm not sure (as I haven't seen one for a while), but if there was a case of attenuation increasing by 6dB from baseline (ie- the figure reported when you will have first had ADSL activated), then there was such a thing as a RADE1 task built by the ISP's. This meant an engineer who knows about attenuation etc would be despatched, in order to bring the attenuation back to  (or better than) the original baseline.
Not sure if this can be done on a FTTC job, but tbh, the fault does sound like a RADE1 on the D-side rather than on the Fibre side.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 18, 2011, 05:33:07 PM
Quote
Regarding the Modem mate, E-bay's yer best bet I would guess. Apart from the fact that, all stores allocated to an individual are itemised and billed to that individuals OUC (Manager in other words), It would be foolish of me to risk my livelihood (sp) over a Modem. Jobs are precious these days, and apart from the micro-managing and i-POP, I like mine. ;D ;D


@ b*cat,

Have you noticed the PM that I sent to you?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 18, 2011, 06:15:53 PM
@ b*cat,

Have you noticed the PM that I sent to you?

Indeed I have, Mr Eagle. There should be a significant stream of electrons flowing from Suffolk to Lancashire. ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 18, 2011, 08:34:31 PM
Addendum to my post further up this thread re: the attenaution from the PCP to the EU's. It was as said, 13.5dB on a 488mtr length of wire ......... and 95% of this was made up of Aliminium. The EU still received 39.9Meg on the DS.

 ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 18, 2011, 09:43:32 PM
Addendum to my post further up this thread re: the attenaution from the PCP to the EU's. It was as said, 13.5dB on a 488mtr length of wire ......... and 95% of this was made up of Aliminium. The EU still received 39.9Meg on the DS.

 ;D

Just curious razpag, did you obtain the 488m length from the JDSU, or by some other means?

488m = 0.3 miles (approx)

0.5 miles = 805m (approx)

Roughly, what do you reckon the attenuation should be for 0.5 miles (805m)?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 18, 2011, 11:31:16 PM
By the only means of divination available to me (catch a passing young rat, slaughter it, disembowel it, scatter and study the entrails :tongue: ) I have come up with the range of approximately 15 - 18 dB attenuation, for a distance of 0.5 mile, of an average copper pair, at VDSL2 frequencies.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 18, 2011, 11:43:02 PM

 I have come up with the range of approximately 15 - 18 dB attenuation, for a distance of 0.5 mile, of an average copper pair, at VDSL2 frequencies.


Go on then, what's the formula?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 19, 2011, 12:05:30 AM
First catch the rat . . . :P

O.k. What I did was to ignore the fact that were are talking about VDSL2 frequencies and to plug a selection of line lengths into Kitz' Maximum Speed Calculator (http://www.kitz.co.uk/adsl/max_speed_calc.php). Once I had the typical attenuation values for the two line lengths of interest at ADSL frequencies, I made a rather crude approximation that, over the same line lengths, the relationship of the attenuation values tends to be linear. Crude scribbled sums on my notepad resulted in the 15 to 18 dB range being ringed at the bottom.

I would be interested to know if Mr Pag has any real observed data that we could use but considering what he has recently written, I suspect that none is available. :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 19, 2011, 12:37:25 AM
Just for curiosity, I tried the Kitz ADSL calculator the other day, using my 30.2 dB attenuation.

The result was 2.2 km or 1.4 miles, almost 3 times my likely line length, but I had no idea what effect different frequencies/SNR etc. would have when considering VDSL2.

razpag's readings were of great interest as they gave me a slight indication of what I should be expecting, especially as most of the line was aluminium (which has been suggested for my line's probable age).

Ideally he'll do a 0.5 mile installation tomorrow & post the results here :)

On Monday, when my line is all fixed again, I'll post my results & brag about my super duper speeds. ;D

EDIT:

Some sort of a record including theoretical & actual results would be quite useful for cases like mine (& no doubt for others in the same position).

If anyone knows where there is such a record for FTTC (I can't find one anywhere), please let me know.

Alternatively, if anyone wishes to post their stats (not at all easy to obtain), I'll start one off.
I could do with a bit of help regarding theoretical values though as I haven't sussed out how to calculate them for FTTC.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 19, 2011, 11:45:06 AM
@ razpag,

I have just read the older thread regarding the Eclipse test. I'm glad you mentioned it.

Useful info to add to my checklist for Monday..................just in case.

Woosh test? Could this be relevant?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 19, 2011, 12:40:19 PM
@ razpag,

I have just read the older thread regarding the Eclipse test. I'm glad you mentioned it.

Useful info to add to my checklist for Monday..................just in case.

Woosh test? Could this be relevant?

Paul.

The engineer will NOT have WOOSH access. This is a facility we used to have (don't get me started) but now only certain elements of Openreach along with BT Wholesale, have this access. It's basically a tool that allows them to 'talk' to your Hub/Router to see current stats. But the best bit is, it also has the RRT which can view your circuit historically. If you recall, I mentioned somewehere about how the 'baseline' is logged on RRT which should show the attenuation when the broadband was first connected.

I honestly don't know if other ISP's can view WHOOSH, or have their own form of it ??? 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 19, 2011, 07:58:17 PM
Hi
@BC No need to scribble I used the same method but just something near what you would expect say 10db then adjust until 0.8 distance was shown.result 11db. Saves the old grey matter  :)

more info  at http://www.internode.on.net/residential/adsl_broadband/easy_broadband/performance/including (fromKitz acknowledgement.)

It only goes up to 24000kbps , but you can see that even at 24000kbps the distance is much more critical ,anything above  900 Metres then there is a rapid loss of Synch rate . So it would seem reasonable to assume on a nominal 40000kbps there would be some losses in synch rate starting at about 500 to 600 metres Metres  to the cabinet (FTTC)
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 19, 2011, 09:26:09 PM
Jeff,

Thank you for the link. Once I had removed the trailing "/including", I then saw the page with the graph. So using your means of estimation, what sort of DS attenuation do you think Baldy Mr Eagle should have with a 805 metre D-side pair?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 20, 2011, 07:19:31 AM
Addendum to my post further up this thread re: the attenaution from the PCP to the EU's. It was as said, 13.5dB on a 488mtr length of wire ......... and 95% of this was made up of Aliminium. The EU still received 39.9Meg on the DS.

 ;D

Just curious razpag, did you obtain the 488m length from the JDSU, or by some other means?

488m = 0.3 miles (approx)

0.5 miles = 805m (approx)

Roughly, what do you reckon the attenuation should be for 0.5 miles (805m)?

Paul.

Apologies, I missed this post for some reason ??

I acquired the total metreage, by adding together the different lengths of cable in the ground from PCP to DP. These lengths are shown on our 'Network Records' programme installed on our laptops. We then have a 'ruler' function that allows you to manually measure from point A to point B, in this case from the DP to the premises which is the length of the dropwire in effect. The figue I quoted will have a +/- factor, but it won't be that far out, believe me. ;)

Just one other point that I forgot to mention. The quoted attenuation figure on this job (13.5dB) taken at the EU's with my JDSU will be higher than the true figure reported once the EU's kit is plugged in. The reason being the resistances in the JDSU are higher than standard Hubs/Routers. So, the actual reading testing via WHOOSH may be approx 11dB. 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 20, 2011, 07:48:34 AM

I acquired the total metreage, by adding together the different lengths of cable in the ground from PCP to DP. These lengths are shown on our 'Network Records' programme installed on our laptops. We then have a 'ruler' function that allows you to manually measure from point A to point B, in this case from the DP to the premises which is the length of the dropwire in effect. The figue I quoted will have a +/- factor, but it won't be that far out, believe me. ;)


Cheers razpag,

Do I take it that all engineers carry laptops with access to the Network Records programme?

If so, Monday's engineer will be able to confirm once & for all, the actual line length & actual line route from the PCP to my home then?

This would then remove any doubt regarding "theoretical" speed estimates based on reported line length rather than actual line length etc.

Do you have any idea of the line attenuation thresholds where BT actually accept a "reportable fault"?
i.e. Assuming 800m line length, are my 30.2 dB DS & 52.9 dB US line attenuations "within specification" & therefore not classed as a reportable fault?

Also, I believe the JDSU is able to report line length (possibly calculated based upon actual line conditions)?

Did you notice that measurement from your recent install job, to compare against the Network records?

I'm sure you must have taken a peek at your own JDSU line stats at your home.
How do they actually compare against theoretical estimated speeds obtained from BT's online line checker, attenuation SNR etc?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 20, 2011, 01:29:21 PM
Not enough time to respond in full, as off out on t'lash with t'lads in 10 mins. Just waiting for my taxi to show up. If I forget to respond more comprehensively later, then yes, all engineers have Network Records on their laptops, (and this will give you a 99% accurate distance you are from the PCP). Whether they can use them or not, is a flip of a coin. It generally depends on the engineers skill-set as to the probability of using Network Records. I'm talking generally here, so any OR pedants please take it as so. ;D

Will try to go more in- depth tomorrow Paul, as no doubt I'll be talking scrotums later tonight.  ;) ;D

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 20, 2011, 07:11:51 PM
Hi
quote @BC:what sort of DS attenuation do you think Baldy Mr Eagle should have with a 805 metre D-side pair?
As per my previous post 11db ( RP's caculations and Kitz's calculations agree :))
The graph is used to show the effects of distance/attenuation on synch rate for a given connection  8000,24000 Kbps. The attenuation is not affected by the the max rate for the line .

If you meant what sort of synch to expect at 800 metres then with a little bit of fiddling and analysing the graph and extrapulating for a 40000 Kbps ,that if the line was top quality might make 35000Kbps .But that is only a guesstimate, probably a little lower in real life say about 30000Kbps.
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 20, 2011, 09:39:52 PM
Purr. (Translation: Thank you.) ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 21, 2011, 12:48:05 AM
@ Jefbb,

To a first approximation, your speed estimation is roughly what Paul was achieving just after his FTTC service was installed.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 21, 2011, 08:25:16 AM
@ razpag

Plusnet's notes on my ticket regarding Monday's visit include this comment:-
"PSTN engineer booked to check for HR fault on D-side which may be affecting broadband
speed."

Just to TRY to ensure that no stone is left unturned, from what I have read, this is my understanding of what the engineer should be checking:-

a) TDR test on the D-side from the original PCP

b) From the JDSU, FTTC Connection speed, Line Attenuation, SNR, line length from the PCP

c) TDR test from my master socket

d) From the JDSU, FTTC Connection speed, Line Attenuation, SNR, line length from my master socket on arrival

e) Line length & line route from Network Records, accessible via the engineer's laptop

f) Results of the Eclipse test

g) From the JDSU, FTTC Connection speed, Line Attenuation, SNR, line length from my master socket on departure

h) A request by the engineer to BT to reset my profile.

i) Has a "lift & shift" been carried out at the PCP

I will run BT Performance Tests & speedtest.net speed test in the morning, & assuming the engineer calls me to say he is on his way, immediately run the tests again (1 hour wait between BT Performance Tests).

Question 1) Have I missed anything, or incorrectly listed anything?

Question 2) Can the engineer manually "reset" anything at the DSLAM in the PCP?

Question 3) As a PSTN engineer has been booked, will he actually automatically run the FTTC tests, or just look for a "voice" fault?

Question 4) If, as previously, the engineer "politely" refuses to, or doesn't know how to carry out any broadband related tests and/or remedial work, what can I do about it?

Question 5) If all the relevant tests have been carried out & everything is "LTOK", what else, if anything, can be explored?

Question 6) Will the engineer have access, either on site or via phone contact with BT, to records of the line condition & FTTC speeds from the original installation date (24/06/2011)? If so, what is the name of they sytem in which these records are stored?
Plusnet have confirmed they do not have access to these details.

I may be worrying unnecessarily. However, as communications to the engineer at the sharp end don't appear to filter through in full, I am concerned that either the "wrong" type of engineer will be visiting again, or that his/her instructions for the visit are not as comprehensive as perhaps they could be.

To everyone:-

Thank you all so much for your help, comments, advice, time spent behind the scenes loking into this matter for me etc.
I only recently registered with Kitz & am amazed at the time & effort you put in for complete strangers who immediately bombard you with questions (& write long rampling posts).

I have learned so much in such a short space of time, & I hope that I may be able to pass some of this knowledge/understanding on to other unfortunate souls in the same boat as me.

Hopefully, one of my posts on Monday will be to confirm that a "fault" was located & repaired & that I have ended up with a stable line & regained my previously fantastic FTTC speeds.

Best regards to all,

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 21, 2011, 09:05:43 AM

If you meant what sort of synch to expect at 800 metres then with a little bit of fiddling and analysing the graph and extrapulating for a 40000 Kbps ,that if the line was top quality might make 35000Kbps .But that is only a guesstimate, probably a little lower in real life say about 30000Kbps.
Regards Jeff


@jeffbb

I have downloaded the spreadsheet (version 1.4) that I believe the Kitz Calculator was based on. I have attached it for reference.

I have no idea whatsover whether VDSL2 & ADSL2+ both function the same way regarding the effect of attenuation.

Entering an attenuation of the 13.5 dB that razpag quoted from his recent FTTC installation, the resulting calculated line length is 978m.
This is almost exactly twice the 488m that was gleaned from BT's Network Records.

The suggested ADSL2+ Attainable Rate from the calculation is 22612 kb/s.

This equates to approximately 94% of the maximum 24000 kb/s for ADSL2+

Assuming twice the 800m that I THINK is my physical line length, an attenuation of 22 DB gives a line length of 1593m.
For ADSL2+, this suggests an attainable rate of 19535 kb/s, roughly equal to 81.4% of the 24000 kb/s.

Again on an assumption that ADSL2+ & VDSL2 function the same, 81.4% of the 40000 kb/s for FTTC would be 32560 kb/s.

This may be pure coincidence, but initially I was actually achieving download speeds in this region, occasionally over 33000 kb/s.

As download speeds are always some value less than sync speed, is this more or less how you derived your estimated theoretical sync speed of 35000 kb/s for my circumstances?

EDIT:

Just as an aside, my 30.2 dB attenuation as reported by the JDSU gives an approximate line length of 2200m & an ADSL2+ attainable speed of 15132 kb/s (63% of the 24000 kb/s).

For FTTC, 63% of the 40000 kb/s would be 25220 kb/s. My IP Profile has gone up & down quite a lot in the last few weeks, & therefore the sync speeds must have also fluctuated.

If any of the above assumptions do stack up, it would reinforce our theory that my Line Attenuation MUST have increased since the original installation (also reinforcing the possibly intermittent high resistance fault theory) from when I was achieving downloads of around 32000-33000 kb/s.

All the above calculations have assumed a cable loss of 13.81 dB/km.
Is this a reasonable average value for a mixture of copper & aluminium as used in the UK, or is it a typical value for good quality copper?

Getting Monday's PSTN engineer to deal with this accordingly may well prove to be a completeley different ball game though.
It would probably take all his allocated 2 hours just to explain the issues
:lol:

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 21, 2011, 02:01:54 PM
Hi

Rather than take the questions one at a time, I'll attempt to explain the skill-sets of different engineers and encompass your queries within the post.

You say you are getting a 'PSTN Engineer' on Monday. That is what we refer to as a 'Network Engineering visit', as opposed to a 'Broadband Engineering visit'. As such, the ECBT (Estimated come back time) will probably be less than the 2hours allocated to Broadband jobs. However, these timelines are only a guide as to how long historically, and as an average, a 'Noisy LTOK' type fault will take. Anything over this ECBT and the engineer will then be 'inefficient'. TBH, the eventual 'Clear-code' the engineer uses when closing the job, is what our performance system (i-POP) actually looks at and generates the stats from. Slightly off at a tangent, I know, but time is precious on tasks and I just want to make you aware that he/she won't want to be subject to the whole sordid tale, just make them aware in a potted format of whats gone on and what advice you've been given from engineers. My major concern is that you have a 'Network Engineering visit', so unless he's 1)Broadband trained and 2)Willing ........ he won't entertain anything you have to say about speeds, attenuation etc etc. Not because he's being awkward, but because he's not there to work on the DSL part of the circuit, just the PSTN (Telephone-speech).

The skill sets then. The lowest single skill (IMO) is the Frames Engineer. He's the guy in the exchange running 'Jumper wires' connecting up telephony and DSL and putting them through to the Bar/Pair (Fuses) that feed the Cabinet that in turn feeds the EU's premises.     

Now then, with a 'Noisy LTOK' type fault, there is an extremely high chance of just getting a CAL/OMI engineer. Customer Apparatus and Line/ One Man Installer. This is really a very basic skill which sees them only working from the top of the telegraph pole into the EU's premises. So if there's a fault on the underground cables, they will have to either 'further' the job to an engineer with the right skills, or try a 'D-side pair change' from PCP to the Telegraph Pole.

If your premises are fed via an underground feed, rather than overhead, there's a chance you may get a CSE Engineer (Customer Services Engineer). This animal is trained to work on all parts of the plant and as such sticks with the job unless he too has to 'further' the task for a reason, such as safety, no line plant, traffic lights etc etc.

FJ. This is a Faultsman Jointer and basically he works on only the underground plant.

The cream of the crop are CSE with Broadband/Fibre skilled engineers (well, I would say that  :blush:), who, even though they are attending on a 'Network' visit, will sometimes and with time permitting, carry out DSL checks as well, in order to alleviate the EU's worries that the line may still be faulty. It really is down to who the engineer is and the relevant skill-set he has.

I do know that Broadband/FTTC repair is tagged to the CAL/OMI queues in 'Works Manager'. This is the machine that automatically 'Pins' the work out to engineers. Myself and others have argued that only CSE's should be upskilled to BB/FTTC, as we do get underground faults from time to time. As time goes by though, more and more CSE's are getting this training and IMO, giving a better service to ISP's and their EU's. Just to add my own personal bitter point, the 'cream of the crop' engineers do all the jobs above, including the Frames, and get paid exactly the same as the Frames Engineer. Ridiculous state of affairs that even Frames Engineers agree with, >:(

As we know, you're getting a 'Network' visit, so a lot of your Broadband questions won't be getting answered I'm afraid. What I would personally do though if it was me attending on this 'Network' visit (so no Broadband faulting techniques), is to go straight to site. Strip the socket down so I'm effectively connecting straight onto the pair of wires coming from outside. Then my first job would be to perform a PQT (Pair Quality Test) which is a high-end test that can unfortunately still not see a 'HR'. Also bear in mind not all engineers can do a PQT. I would then spend 10 mins listening on 17070 (Quiet Line Test). If noise is heard, or not, I would then proceed to attach a TDR meter and try to find a 'HR'. If one doesn't present itself, I would then ring the PSTN number with the TDR meter still attatched and continue looking for HR's. The higher AC voltages that ringing generates, sometimes shows the 'HR' when it's in its infancy so to speak. For info ... TDR is always best when testing back towards a voltage, rather than on a 'dead' pair.
If that still doesn't show anything, I would then head to the Cabinet and disconnect the D-side and perform a 'Leg Balance' test. This does as it says on the tin. It measures each leg seperately and will always give an accurate reading no matter how small the 'HR'. Along with this, I would perform other tests such as looking for 'Battery' or 'Earth' contact faults, that a low-end test like 'Eclipse', 'RAT' and 'TAMS' can't see. There could for instance be 3/4/5 V of 'Battery Contact' on your line and 'Eclipse' will still give a 'LTOK' result. If everything passes and the line is quiet at the Cabinet, there's not much else I could actually do.
If it was a Broadband Engineering Visit, I would do all the above plus run a DSL test and look for errors etc etc.

Regarding 'Network Records' that you ask about. All engineers have them on their Laptops, but as I've said earlier it rather depends on the engineer as to whether he can use them or not. In my experience, CAL/OMI engineers don't know how to use them but there are exceptions to the rule. FJ's and CSE's will definitely know how to use them.

I hope this answers some of your questions, and apologies if I've missed something. Your queries about DSLAM's, Lift & Shift etc ,are fruitless however because of the type of task you say has been built against your premises. Me persoanlly, I would have rather you had a 'Broadband Engineering Visit' from a CSE. That way everything is encompassed within the skill-set. Lets not panic just yet though, as you may get a great engineer who does indeed find a fault of some kind and then it's happy days again. Best of luck Paul. ;) ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Ezzer on August 21, 2011, 02:33:07 PM
Made intersting reading for me Razpag. the patch I was in was predominately all multiskilled CSE's and the frames guys (and lady) typicaly ex cse's

Broadband was a specialist group when I first started on dsl for 3 patches before we blended back into normal teams and passed as much info on to the other cse's as they wanted to soak up.

Heard a bit about the greater demarcation in other areas. But the great thing about being a cse was you get a task, so just get it working.

I could never just stick to frames, getting about 3-4 frames tasks was enough for me in one go. it would drive me mad doing nothing but.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 21, 2011, 02:50:47 PM
All felines are inquisitive, so having read RP's detailed description, I wonder:

1) "ring the PSTN number with the TDR meter still attatched and continue looking for HR" -- Call the EU's number from your mobile phone?

2) "disconnect the D-side and perform a 'Leg Balance' test. This does as it says on the tin. It measures each leg seperately and will always give an accurate reading no matter how small the 'HR'." -- Would that be to short both legs of the pair, connecting them to earth at one end and then use a suitable device, some form of bridge, perhaps even an 18C at t'other?

 :hmm:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 21, 2011, 02:51:07 PM
@ RP & Ezzer,

VERY WELL DONE

That is the most comprehensive essay I've seen on the different types of BT O engineer and is absolutely invaluable for amateurs.

I know we're probably little more than hobbyists in your eyes ( and some might say B****y nuisances) but with such a rigid over-managed structure it certainly helps us to suggest what an SP might request of BT O.

I hope that we all can recognise the benefit of a) getting the EU's proper services (s)he's paying for restored, b) keeping the Telco's and the ISPs' costs to the minimum and c) helping to familiarise and enhance the capabilities of the lower order BT engineers.

Kindest regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 21, 2011, 02:52:22 PM
Made intersting reading for me Razpag. the patch I was in was predominately all multiskilled CSE's and the frames guys (and lady) typicaly ex cse's

Broadband was a specialist group when I first started on dsl for 3 patches before we blended back into normal teams and passed as much info on to the other cse's as they wanted to soak up.

Heard a bit about the greater demarcation in other areas. But the great thing about being a cse was you get a task, so just get it working.

I could never just stick to frames, getting about 3-4 frames tasks was enough for me in one go. it would drive me mad doing nothing but.

I believe here in the central UK, we have the biggest speration of skills. Can you remember a certain Mr R. King and SMT/FRS ??, along with all the debate about fairness ?? It was he who informed me of this after continually bombarding him with questions. The rest of the UK are indeed mainly CSE skilled. The problem is the OP lives in Oldham (Cental UK).  ???

Oh how I concur with you regarding Frames work. I would seriously end up being sectioned having to perform those tasks day in and day out !!  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 21, 2011, 02:54:33 PM
All felines are inquisitive, so having read RP's detailed description, I wonder:

1) "ring the PSTN number with the TDR meter still attatched and continue looking for HR" -- Call the EU's number from your mobile phone?

2) "disconnect the D-side and perform a 'Leg Balance' test. This does as it says on the tin. It measures each leg seperately and will always give an accurate reading no matter how small the 'HR'." -- Would that be to short both legs of the pair, connecting them to earth at one end and then use a suitable device, some form of bridge, perhaps even an 18C at t'other?

 :hmm:

Hi Cat

1) Yes

2) There are different ways to perform different tests BC, but on this occasion I mean to test to an 'open' circuit.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 21, 2011, 03:01:43 PM
Quote
2) There are different ways to perform different tests BC, but on this occasion I mean to test to an 'open' circuit.

Ah, thank you. That particular itch has been "well scratched". :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 21, 2011, 03:02:09 PM
@ RP & Ezzer,

VERY WELL DONE

That is the most comprehensive essay I've seen on the different types of BT O engineer and is absolutely invaluable for amateurs.

I know we're probably little more than hobbyists in your eyes ( and some might say B****y nuisances) but with such a rigid over-managed structure it certainly helps us to suggest what an SP might request of BT O.

I hope that we all can recognise the benefit of a) getting the EU's proper services (s)he's paying for restored, b) keeping the Telco's and the ISPs' costs to the minimum and c) helping to familiarise and enhance the capabilities of the lower order BT engineers.

Kindest regards,
Walter

Hi Walter

Our new CEO (Liv Garfield) has stated that she has improved the training budget 3-fold. Along with improving the laptops and testing equipment we have. By that, I mean upgrading engineers old kits for new ones, and I do believe we are to get O-Phones ??

The days of listening on with a 'tapper' to fault find are long gone. Up to 4.2Khz circuits for residential premises, are slowly becoming superceeded by higher DSL frequencies whereby faulting can only be truly completed by using meters. That's why the need for up-skilling is paramount for engineers, not just to give ISP's and their EU's a better customer experience (Jeez, I sound like my boss  ;D), but also to give the engineer more job security ....... if there is such a thing nowadays.  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Ezzer on August 21, 2011, 03:09:20 PM
Can you remember a certain Mr R. King and SMT/FRS ??,   :o

Do I remember, oh my god and Mr Rod King wasnt it ?

Half a mo'!  :doh: 'Razpag' ? Wern't you on the dg at the time as Razpag ? This is ringing some bells (bell external I think). If so I was Ezzer on the dg at the time too.

If I remember this right you certainly were giving him a barrage of questions on everyones behalf. And his answers.....well..... That takes me back.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 21, 2011, 03:20:04 PM
He he he ..... that was indeed my goodself pal. Yes, Mr Rod King, I got a personal phone call from him due to the to-ing and fro-ing of heated debate. ;D He's actually a really nice guy and I'm wise enough to understand he was just doing his job. I just wanted to point out the unfairness of the sytem, along with others.

What we have now unfortunately, is FRS/SMT but without the cash incentive !! Damn !! ;D

The old DG was a tough place to be at times. Got plenty of calls from Ajay and T.McDonald (IT Sols Moderators) to be asked to wind it in a bit. Bit like on here sometimes. ;) ;D Joke Eric. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 21, 2011, 03:48:42 PM
Hi
@Baldeagle: Did you have a connection before FTTC?if so do you remember ?know the SYNCH rate ?

Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 21, 2011, 05:23:16 PM
Hi

Rather than take the questions one at a time, I'll attempt to explain the skill-sets of different engineers and encompass your queries within the post.


@razpag,

Thanks very much for the detailed explanation of who does what & what I should expect/not expect tomorrow.

As my ISP ticket states "PSTN engineer booked to check for HR fault on D-side which may be affecting broadband
speed.", I would like to think this has been communicated with the various parts of BT that organise the relevant engineer(s) for the "fault" in hand.

i.e. Locate the intermittent fault & fix the phone line, then check whether or not this has also fixed the broadband speed issue(s).

I can't realistically pursue the broadband speed issue until the phone line is given a clean bill of health.
If no phone line faults are found, the next stage will be to obtain an explanation & remedy for the broadband speed reductions, although if the fault is intermittent, it may/may not br found tomorrow.
I don't know if the symptoms are the same, but I really do hope this is not a REIN issue.

I also hope I don't have to take even more time off work to pursue this matter.

Thanks agian for all your help & advice.
It really has helped to turn a "no fault found & you are achieving more than the estimated speed so bu@@er off" matter into something that is now actually being taken as a genuine issue, certainly by Plusnet.

P.S. I have been quiet today as it is Mrs. Baldy's birthday & I have also been building her a new kitchen.
I'm sure a nice bunch of flowers would have been a lot easier ;D

Regards,

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 21, 2011, 05:32:29 PM
Hi
@Baldeagle: Did you have a connection before FTTC?if so do you remember ?know the SYNCH rate ?

Regards Jeff


If you could call it a connection, yes.

1 Mb on ADSL1. That's all I expected & that's all I got due to the real distance from the exchange.

Please see the attached screenshot from DMT.EXE that I used, almost from day 1.

This was the best download speed that I ever achieved, but look at the upload speed (It wasn't always that low though).

My current upload attenuation appears very high at 52.9 dB.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 21, 2011, 06:35:12 PM
Hi
My current upload attenuation appears very high at 52.9 dB.   ?

Where do you get this data ?

seems odd

Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 21, 2011, 06:40:10 PM
Is it not that his original US attenuation was lower as the DSL frequencies are smaller on ADSL1 ??
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 21, 2011, 06:46:36 PM
Hi
My current upload attenuation appears very high at 52.9 dB.   ?

Where do you get this data ?

seems odd

Regards Jeff


@jeffbb,
The stats came from the JDSU as used during the most recent engineer's visit. Please see the attached photo.

As the relevant distance is now only to the cabinet & not all the way back to the exchange, should the US & DS line attenuations be roughly the same for FTTC, or does the large difference between the two values simply reinforce our thoughts that there is some sort of high resistance issue on my line?

EDIT:

I notice from asbokid's screenshots where he had managed to access the HG612 modem, that his attenuations were 19 dB DS & only 6 dB upstream - in effect reversed when compared to mine.



Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 08:49:53 AM
Just a thought, while I am sat here waiting for the BT engineer..............

My US Line Attenuation was 52.9 dB when tested via the JDSU.

This appears rather high when considering the relatively short distance to the cabinet.

The JDSU reported an US Max Rate of 5212K & an Actual Rate of 1996K.

My "Plusnet Value Fibre" package is restricted to "Up to 40 MB downloads" & "Up to 2 Mb" uploads.

Even with the more expensive Plusnet packages, the US is capped at 5 Mb, apart from for users that participated in Plusnet's Fibre Trials. I believe these users are allowed an US of up to 10 Mb.

I don't know how this "capping" of ISP packages works, but is it possible that restricting my upstream to 2 Mb will actually have the effect of increasing the Line Attenuation?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 22, 2011, 09:11:50 AM
Hi Paul,

I don't think that any capping restrictions have any bearing on the physical attenuation values.

I believe there are a few ISPs offering the two upstream rates as BT do, presumably because the wholesale costs are too high ?

Kind regards,
walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 11:47:22 AM
PSTN Engineer's Visit, Monday 22/08/2011

The PSTN Engineer arrived without calling in advance.

This was not a problem as I had gathered my "before" stats earlier on & I was just glad that it wasn't another missed appointment.

We discussed a brief summary of the issues (brief, me? YES IT WAS brief :lol:)

The engineer was very friendly, helpful & talkative, explaining everything he was doing as he went along (despite the lack of chocolate biscuits & bacon butties).
He did explain that as he was a CSE regarding PSTN only, he would not be able to check any broadband matters as he just did not have the equipment.
He did say though that if he managed to track down & repair a line fault, the broadband speed issues would probably be resolved aswell.

He did the usual "Quiet Line" stuff, & checked my internal wiring etc.

Then he whipped out his HAWK tester to do the all important TDR test.

He mentioned he could see "something strange" near the cabinet, but unfortunately I missed the chance to take a photo.

Before going down to the cabinet he disconnected my equipment & attached as Oscillator 87J to my master test socket (photo attached) & also hovered a small "gadget" near the master socket, power adaptors, & my shielded "extension" cable.
This "gadget" hummed/buzzed a little, but the engineer said averything seemed O.K. at my house.

Anyway, he came back from the cabinet & using words like "absolute stupidity", he explained that he had found that "someone" had "double jumpered" another D-side cable onto the fibre connection that my D-side was connected to, & that was probably the explanation for the broadband disconnections, crackly phone line etc.
He confirmed that he had disconnected the "extra/redundant" cable.
Has someone been stealing my broadband & will the next call to BT be that another end user has suddenly & completely lost their telephone and/or broadband services?

While we were chatting about this, the engineer brought up BT's Network Records on his laptop.
He showed me the actual route & confirmed the ACTUAL line length from the cabinet is only 820m & allowing a bit of slack for pole drops/connections etc. we should consider 850m as the absolute maximum line length.
I have a photo of the line route for my own reference, but the engineer asked me not to post it anywhere public.
As the engineer was so helpful. I will fully respect his request.

We ran a couple of speed tests along with the BT Performance test just before the engineer left.
The results were a slight improvement from earlier this morning, the BT Performance test showing an IP Profile of 21680 K, download speed of 20022 K & the acceptable range of speeds as 15175 K to 21680 K.

The engineer mentioned that for those on Infinity, following a line "repair", previously high speeds are usually restored almost instantly.
He advised me to request (via Plusnet) a Broadband Engineer to investigate if the speeds did not automatically increase within the next few hours.
He also confirmed that a 35 Mb IP Profile & 32-33 Mb download speeds looked "about right" for my ACTUAL line length & quality.

As he didn't have a JDSU & wasn't a broadband engineer, unfortunately the engineer was unable to confirm my line stats such as attenuation, Max Rate etc.
He was also unable to request BT to reset my profile for the same reason.

I did show the engineer a couple of comments from this forum (thanks razpag et al) & he also commented it was a "pleasure" to be speaking with an end user that had obviously researched & actually knew a bit about matters.

I'm not sure if he was just being polite though.
Personally I really hate it when "know all" clients start telling me all the technical detail they know about my job ;)

So, I have updated my Plusnet ticket & the engineer will update BT's records too, & time will tell whether or not I get my high speeds back again.

Watch this space :)


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 22, 2011, 12:13:45 PM
Quick reply. Great result. You will deffo get your max 33Meg speeds back, as the attenuation was to high before due to being 'double jumpered'. Why it's taken so many engineers to do what this chap did this morning is crazy ??
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 12:32:38 PM

Quick reply. Great result. You will deffo get your max 33Meg speeds back, as the attenuation was to high before due to being 'double jumpered'. Why it's taken so many engineers to do what this chap did this morning is crazy ??


Hmmmm,

Not today methinks.

Lost connection at 12:05.
Phone crackling again.
Phoned Plusnet. William could hear the crackling.
Back to square bloody one >:( >:( >:(

Paul.

EDIT:
If only I could see the modem stats I would have a bit of a clue as to what's going on!!!!!!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 22, 2011, 12:38:57 PM
Hi Paul,

Given that you have now been though the motions with the phone line engineer, I suggest you should insist that a fully skilled VDSL engineer is called in as soon as possible.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 02:05:29 PM
While the engineer was here this morning, we talked very briefly about potential REIN issues.
He admitted he wasn't too clued in REIN matters, but cited a couple of examples that he had heard of such as where an end users TV had caused them.

I really hope this isn't ultimately a REIN issue as, from what I can gather, it can takes many months to sort out (if you are lucky).

I have asked my immediate neighbour if she switched anything on at around the time of the disconnection & crackly phone today e.g. microwave, cooker, kettle (it was around lunch time & my modem / PC setup backs directly onto her kitchen).
She can't recall doing so (apart from her laptop to go & Google a few things), & as the weather is quite warm & sunny again, we can rule out central heating pumps etc.

If/when it happens again, I'll ask if she has just switched her laptop on again.

Everything apart from my Sky box (in standby mode) is/was switched off in my house too.

I can't find a definitive answer anywhere, so do any of you know whether or not the symptoms of REIN are similar to my issue(s), i.e. intermittent disconnections & an also intermittently crackly phone line?
I hope the answer is no, they are completely different, but....................


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 22, 2011, 02:27:00 PM
From my experiences in the electrical machinery repair industry, my experience with radios a bad or poor joint will give you the symptoms that you have. I know I'm not talking telecommunications here, but if one rubs two bare wires together briefly one will get a make and break situation. Thus putting a crackle on audio equipment.
Can you describe the crackling in a bit more detail please? Is it like a buzz or like I describe with the wire scenario?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 02:51:31 PM

Can you describe the crackling in a bit more detail please? Is it like a buzz or like I describe with the wire scenario?


Hi silversurfer44,

It is definitely not at all like a buzz.

I would describe it more as a definite, but intermittent crackly sound, with an occasional clicking sound & maybe a slight hiss inbetween.

When it stops (it has never lasted for more than a couple of minutes or so & can go for quite a few days at a time with no symptoms at all), the phone line is perfectly silent again.

I am hoping it is just a dry joint somewhere in the cable, or even at the cabinet, (or something similar) that just needs to be tracked down & fixed.

Today's TDR test apparently didn't pick it up though, although the engineer did not retest via TDR after he had removed the "double jumpering".
I did ask, but he said it wouldn't need retesting as he had located & fixed the "fault".

FYI, the weather was warm, dry, & without any breeze when I experienced today's disconnection & crackly phone.
I have also experienced the same symptoms, but not as often, when it has been wet & cold.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 22, 2011, 03:00:44 PM
Quote
but he said it wouldn't need retesting as he had located & fixed the "fault"
That was a fatal mistake. I suppose most of the visits ended on a similar note.
By your description of the crackle it does sound like a faulty line. I can say no more as I am not as telephone savvy as the other guys. No doubt they will be able to comment.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 03:10:52 PM

That was a fatal mistake. I suppose most of the visits ended on a similar note.
By your description of the crackle it does sound like a faulty line. I can say no more as I am not as telephone savvy as the other guys. No doubt they will be able to comment.


It's the same in my game (building defects) that's why I asked the engineer about retesting.
Maybe/probably I should have been more insistent :doh:

If we have something "fixed", we either test it there & then e.g. rainwater ingress from a suspected defective cavity tray, retested by simulating rain with a hosepipe, or at least monitor it for a suitable period of time.

My towel is out now, & I'm almost ready to throw it in.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 22, 2011, 03:29:09 PM
I learnt a long time ago to test and retest after a repair. With electrical type of gear a fault can develop at any time. If we repaired a piece of machinery and it broke down again within three days it was a severe reprimand, whether the fault was related or not. Now the last engineer seemed to do a good job but in my opinion he didn't finish the job because he didn't retest the circuit.
No doubt someone will start saying time on the job and all that. Well I say if the repair is not tested then the job is not complete, and if there is insufficient time for a test the job should be re-scheduled for as soon as possible.
I salute you for your tenacity Paul, but if I were in your position I would see it through. The person at the other end of the telephone would know that I was not satisfied with the service.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 03:52:08 PM
I learnt a long time ago to test and retest after a repair. With electrical type of gear a fault can develop at any time. If we repaired a piece of machinery and it broke down again within three days it was a severe reprimand, whether the fault was related or not. Now the last engineer seemed to do a good job but in my opinion he didn't finish the job because he didn't retest the circuit.
No doubt someone will start saying time on the job and all that. Well I say if the repair is not tested then the job is not complete, and if there is insufficient time for a test the job should be re-scheduled for as soon as possible.
I salute you for your tenacity Paul, but if I were in your position I would see it through. The person at the other end of the telephone would know that I was not satisfied with the service.

One of my first queries with today's engineer was how long was he allowed to spend on this job.

His response was something like "Unlike the broadband engineers, I can spend as much time as necessary, within reason, until it's fixed. I spent 8 hours on a job recently, but fixed it in the end. The Estimated Come Back Time (ECBT) is just that, an estimate"

Apart from the retesting matter, he seemed really conscientious & actually commented on the lazy bas#%$3s that don't bother whether they actually fix things or not.

He even mentioned the only job he had to leave without a same-day "fix".
He couldn't stop thinking about it, & a day or so later he went to the exchange itself, located a "faulty" line card, had it replaced it & the problem was eventually permanently fixed.

Plusnet informed today me that they are rejecting this "fix" as not completed.
I get the feeling that this particular engineer will be genuinely "gutted" that his efforts today have not actually saved the day for me.

Stay tuned listeners for the next chapter. I've temporarily put the towel back in the cupboard.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 04:28:18 PM
Quick Update:-

Another PSTN engineer has just phoned me to say he has spoken with this morning's engineer in connection with Plusnet's rejection of today's "fix".

He is actually on his way up to see me & "have a listen to my line" as I am typing this message.

He did say it might ultimately require a Broadband Engineer, but nothing ventured, nothing gained.
He also mentioned that he didn't have the right tackle to check my broadband "Line Insinuation".
Bless him  ;)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 22, 2011, 05:11:02 PM
I do sympathise with the engineer who thought he had fixed the fault, well he had fixed A fault but there may well have been another. He should have retested though. With the description of the crackling etc it does sound to me like a POTS fault and nothing to do with the the broadband. If that is the case then the fault has to be between your premises and the cab. Unless I am wrong about the possibility of a fault between you and the exchange.
Have you tried another phone? Just in-case there is a problem with your phone. That should not interfere with the broadband if the phone is on-hook.
Best of luck Paul, stay with it.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 05:37:03 PM

Have you tried another phone? Just in-case there is a problem with your phone. That should not interfere with the broadband if the phone is on-hook.
Best of luck Paul, stay with it.


I have tried all that previously. Everything connected, nothing connected, phones connected one at a time.

It all seems fine for a few days, then BANG, off it goes again.

Today's 2nd PSTN engineer has just left.
Unsurprisingly, the phone line was as quiet as the proverbial mouse again.

He suggested that I contact Plusnet again & insist on a broadband engineer's visit that will have to now check EVERYTHING, including the fibre & PSTN ports at the main exchange, the MFD (or something similar sounding), the equipment in the street cabinet etc. etc. etc.

He didn't think it would be a dry joint on the D-side though.

What a P.I.T.A this is turning out to be!

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 22, 2011, 05:56:08 PM
Yes, it's enough to make you want to pull your hair out doesn't it?
I must bow to the engineers superior knowledge with regard to the D-side fault.
I watch with bated breath for the out come.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 22, 2011, 06:02:10 PM
Some quick comments from The Cattery.

Don't be disheartened, Mr Eagle. Significant advances in the progress to an ultimate resolution of your unhappiness have been made. You now need a visit by a multi-skilled, "broadband-enabled", OR engineer -- complete with his JDSU and other gubbins. Your CP, PlusNet, are now fully behind you and will do the right thing in requesting such a visit. (Remember to stock up on bacon, butties, for the use of, and chocolate biscuits.) The POTS engineer who visited you this morning seems to have been someone with whom I would have enjoyed a discussion. ;)

Give up the battle now :no: and you will disappoint numerous people here. In that case you can expect the most grumpy of black looks >:( from a certain burakku tomu kyatto, who will ensure that his claws are as needle-sharp as possible -- all ready for a paw-swipe, if you should ever come into swiping range! And you wouldn't like that, would you? ::)

[Edited to correct a grammatical faux pas.]
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 06:21:05 PM
I realise this matter could end up potentially quite time consuming & expensive for someone (not me).

But what a fantastic learning curve it is for all involved (including the service providers), that once resolved will surely set precedents & methods for similar fault finding issues in the future, thus making it really cost effective in the longer term?

I just hope that BT & Plusnet both agree to stick with this & don't give up just yet.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 22, 2011, 07:00:52 PM
What a shame BE. Backing the engineer up here, you do seem to have been visited with one of our better ones, and in fairness to him he's TDR'd your line and probably seen something akin to a roller-coaster (or a Sine wave) on his HAWK measuring back to the PCP. He's then left his signalling kit on the line to make sure it appears in the PCP where his routing suggests it will be. Upon finding a 'double-jumpered' circuit, he (like I and any other decent engineer) would have probably been convinced that this was the fault repaired. He must have put the socket back together when returning back from the PCP, and he will have checked for dial tone. Obviously the crackle wasn't there when he did this.

Some might say he was wrong for not re-TDRing the line. I absolutely say he wouldn't have been expecting to. If you take a mains fed Radio to a repair shop with the plug hanging off, when the chap in the shop puts on a new plug would you have him perform diode,resistor, transistor, capacitor checks ?? Would you heck. You'd turn the radio on and when you hear music, you know it works. Same in this scenario, the engineer has found an absolutely blatant, hard & fast fault that WAS causing massive fault attenuation problems. He's repaired that and basically 'switched the radio back on' and got dial tone. Happy days. Who's to say he didn't carry out the 'Leg balance' test at the PCP that I mentioned earlier in the thread, which would also rule out the need for any further TDR tests ??

Anyhows, this tiny, very intemittent crackle that you get sounds like an E-side type noise. D-side faults tend to progressively get worse quite quickly, but E-sides are under constant air-pressure from the ECP racks in the exchange, in order to keep moisture at bay. It may be a drop in pressure (that can and does happen) that is causing the intermittency of this fault ?? Either way, it shouldn't affect the DLM in such a way as to keep your synch down at 22 Meg. By removing the double jumper your speed should go right back up. 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 22, 2011, 07:03:05 PM
PS ...... it most definitelt is NOT REIN if it's a 'crackling' noise.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 22, 2011, 07:20:58 PM
I would like to add to Mr Pag's post script that what is talked about in fora, such as this, as REIN is more often than not the more common RFI.

Replacement of the original type one or type two BT-logo'd NTE5/A with a latest OR-logo'd one (containing the common-mode chokes) or the addition of a BT80B-RF3 in place of a BT80A will resolve all but the most severe RFI. (As b*cat has noted, by personal experiment. ;) )
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 22, 2011, 07:50:56 PM
I had an idea I would be brow beaten for my posts ;D
I let the engineer off the hook a few times, however I pointed out that there is nothing like having another check. Yes he repaired a fault, but it is obvious that there is still a fault. Where or what it is obvious I cannot say. Working practices I can say, much to my cost in early days of training and later years before retiring. As a manufacturer of a tea trolley at school I was taught to measure twice and cut once. Just because the guy was professional and thorough doesn't mean to say he is infallible.

I still say best of luck Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 22, 2011, 08:00:19 PM
I agree with you there SS, re- measure twice, cut once. But unfortunately the same adage cannot be applied to an intemittent fault. I still don't know what another TDR check from the EU's would show ? The engineer could only 'see' something wrong at a distance that measured back at the PCP, and he located and repaired that particular anomoly.

My advice now to BE would be to 'suggest' the next engineer TDR the E-side cable from the PCP back to the exchange.

There was only one bloke who was ever thought to be infallible SS, and they put him on a cross.  ;) ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 22, 2011, 09:36:08 PM
What a shame BE. Backing the engineer up here, you do seem to have been visited with one of our better ones, and in fairness to him he's TDR'd your line and probably seen something akin to a roller-coaster (or a Sine wave) on his HAWK measuring back to the PCP. He's then left his signalling kit on the line to make sure it appears in the PCP where his routing suggests it will be. Upon finding a 'double-jumpered' circuit, he (like I and any other decent engineer) would have probably been convinced that this was the fault repaired. He must have put the socket back together when returning back from the PCP, and he will have checked for dial tone. Obviously the crackle wasn't there when he did this.

Some might say he was wrong for not re-TDRing the line. I absolutely say he wouldn't have been expecting to. If you take a mains fed Radio to a repair shop with the plug hanging off, when the chap in the shop puts on a new plug would you have him perform diode,resistor, transistor, capacitor checks ?? Would you heck. You'd turn the radio on and when you hear music, you know it works. Same in this scenario, the engineer has found an absolutely blatant, hard & fast fault that WAS causing massive fault attenuation problems. He's repaired that and basically 'switched the radio back on' and got dial tone. Happy days. Who's to say he didn't carry out the 'Leg balance' test at the PCP that I mentioned earlier in the thread, which would also rule out the need for any further TDR tests ??

Anyhows, this tiny, very intemittent crackle that you get sounds like an E-side type noise. D-side faults tend to progressively get worse quite quickly, but E-sides are under constant air-pressure from the ECP racks in the exchange, in order to keep moisture at bay. It may be a drop in pressure (that can and does happen) that is causing the intermittency of this fault ?? Either way, it shouldn't affect the DLM in such a way as to keep your synch down at 22 Meg. By removing the double jumper your speed should go right back up.


@ razpag.

I forgot to mention that I brought up the lack of another TDR test from my home when the 2nd engineer visited this afternoon.
He said that the 1st engineer had actually done a TDR test while he was down at the PCP & classed the line as clear.
Maybe that's what he meant when he said another TDR test wasn't needed from my home.

FYI, my IP Profile did increase to 21680 K for a short while after the 1st engineer left, but it is currently at only 12065 K.

I wish I could have seen the effect of of the removal of the double jumpering on my attenuation, as a comparison to when it was quite recently tested via the JDSU.

At the very least, I now know my actual Line Length & its route, which finally confirms beyond any doubt that I should be able to achieve & sustain a sync rate of around 35 Mb (ish), with downloads a little lower than that.

The 1st engineer had a quick read through the notes & recommendations you had so kindly provided, verbally ticking them off as done, apart from the obvious broadband aspects, which he said he would haved loved to have done for me.

I wasn't knocking the efforts of the 1st engineer, I apologise if my post came across that way.
In fact I intended the complete opposite as he couldn't have been more helpful, keen to locate the fault, & informative.

Indeed the phone line was quiet when he left, my IP Profile had increased from when he first arrived, he had dealt with an obvious fault. What more could he have done, especially as the actual intermittent cause may well now prove to be elsewhere?

There probably isn't that much left to eliminate now..........is there?
I suppose that sometimes you are lucky & land on the cause at the outset & sometimes it is the very last thing in the elimination process.

Silly question time now:-
The double jumpering couldn't possibly have been a previous well-meant effort to increase the poundage of my line to compensate for length, corrosion etc. could it? Is this ever done as a quick fix by BT, a bit like bonding 2 lines back in the old days to give a sync rate of was it 128K on dialup? (just trying to think laterally here - maybe I shouldn't!)
If so, could the removal of the double jumpering have actually increased my attenuation by leaving 800m or so of "loose end" if it was still connected somewhere near my home?
It does seem strange that my IP profile didn't shoot all the way up again & is now in fact much worse than it was this morning.

As we all know, there is absolutely no way that we users can obtain any information from the current BT modem. What a strange situation that is.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 22, 2011, 10:57:32 PM
Quote
There probably isn't that much left to eliminate now..........is there?

Just the E-side of your POTS metallic path, I would say.

Having looked at your "Silly Question Time Now" section, I would not expect that to be the case. However, let's see what Mr Pag has to say on that subject.

(P.S. I now have an image, named "Bald_Eagle1_Closet.jpg", stored on my desktop.  :P  )
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 23, 2011, 12:04:25 AM
@ everybody,

Please forgive the reiteration. I hope we can all agree this fault seems to be overworking Murphy's law to the maximum !

1.  It does seem that an engineer with a JDSU or EXFO is even more necessary now.

2.  Perhaps the engineer might just try cutting the E side cable and observing a resync of Paul's modem?

3.  Given that the remote testing must have been done from the PCP rather than the FTTC (as the engineers are not FTTC trained) there still remain the two short 100 pr link cables plus the IDC connector blocks and the still unknown circuitry behind them. I do wish we had a better (any real ?) understanding of that circuitry. In the absence of that data perhaps the engineer might change the two corresponding pairs in those cables and have the cct configuration data changed to recognise the new channel if that is needed? (I'm assuming that the routing data does not rely on the MAC data within the modem?)

4.  I expect RP will give me a rollicking but, if all else fails, the low-tec solution might be to apply a large club hammer to each pole in turn ! However, as we believe there is a possibility of aluminium being involved, the cure might be worse than the disease - at least for BT Openreach. I suppose a more acceptable approach might be to swap the D side pair along the entire length if there are sufficient spares, although I have observed that can be a very time-consuming exercise. (Over a month in the snow and where traffic lights were deployed last winter !)

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 23, 2011, 12:43:38 AM
@Walter,

I think you are possibly too far ahead with trying to think of all the possible fault scenarios and possible solutions. Knowing what we all now understand regarding this issue and if I were the relevant OR engineer assigned to the task, I would:

(1) At "The Aerie", disconnect the incoming pair from the NTE5/A and perform TDR towards the PCP.
(2) At the PCP, disconnect the D-side tie-pair to the DSLAM and perform TDR back to "The Aerie".
(3) Still at the PCP disconnect the E-side tie-pair to the DSLAM and perform TDR back to the exchange.
(4) At the exchange, disconnect the E-side from . . . er, it's not too clear in my mind . . . perhaps the MDF and perform TDR back to the PCP.

Analyse the four results so obtained. If necessary:

(5) Return to the PCP and repeat TDR to the exchange, c.f. (3), now with the exchange disconnected.
(6) Return to "The Aerie" and repeat TDR to the PCP, c.f. (1), now with the D-side completely disconnected.

If all six traces show nothing abnormal, then . . .  :'(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Ezzer on August 23, 2011, 01:32:52 AM
The old 128k connection I presume you are refering to what was known as home highway. its 2 channels of an ISDN signal at 64k each. Combined they give 128k, but if you use the voice telephony it occupies one channel while you still have a net connection at 64k on the other.

This is before the days of dsl when the other option was a 56k dial up where you cannot use the phone and net at the same time and typicaly get between 36-48k. Can everyone remember that ? When the norm was 36-48k !

ISDN was referd to as mid band in europe. Would you belive even in the mid 2000's in the states isdn was still classified as broadband so some figures refering to the numbers of people on broadband during those years can be relatively misleading.

I saw your point about the 2nd TDR test and that it wasnt a slight aimed at the engineer. From the customers point of view you dont get to see when the engineer is running tests on the line from locations other than your nte. The TDR often needs to be tried from a location closer to a fault in order to be able to see it. It becomes almost 2nd nature to have a look whenever you intervene in the network. because at the end of the day if you can get in a situation of being able to go "oh hello ! that looks like it"  ;) rather than "Theres something lurking here, now show your self"  >:(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 23, 2011, 07:31:19 AM
I too know you weren't having a pop at the engineer BE, it was SS my sarcastic post was aimed at. ;)

As Ezzer has explained above, Channel Bonding was applied to ISDN/Highway units if requested. I think you are on about connecting 2 full pairs together (4 wires) on the D-side network in order to give a greater poundage ?? If you are, this is a massive no-no, the AC Balance would be extremely low as it would regard it as a 'split pair'.

I've only 'doubled up' on PSTN lines that were reporting faint ringing.speech and were (from memory) around 13Km from the exchange. I don't work that patch anymore and my poor memory is fading. :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 07:40:28 AM

As Ezzer has explained above, Channel Bonding was applied to ISDN/Highway units if requested. I think you are on about connecting 2 full pairs together (4 wires) on the D-side network in order to give a greater poundage ?? If you are, this is a massive no-no, the AC Balance would be extremely low as it would regard it as a 'split pair'.


@razpag,

The 4 wires to "double up" is what I was wondering. Just trying to cover all bases in my own mind.
I did mention it was a silly question, but other silliness does appear to have gone on at various stages with this issue ;)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 23, 2011, 09:21:56 AM
@ BKK,

Your methods are another approach but I would change your item 2 (or add item 2a) to say disconnect the E side tie pair and perform the TDR to Paul's. You then have the entire cct measured.

Given that the line crackle is highly intermittent and the only constant error indication seems to be the low sync, I still suggest that all engineers working on this fault should at least have access to, and be trained in, the use of a JDSU or EXFO.
Even if a JDSU observation is just the final test, that method would be a good way of finally closing this fault down. That way Mr & Mrs Eagle can resume normal service and return to their domestic bliss !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 10:15:18 AM
FYI, I have only ever noticed the crackling following the modem's disconnection, during the reconnection process (I do keep having a quick listen at other times).

As soon as the modem reconnects (reasonably quickly), the crackling immediately stops.

Could the modem disconnecting/reconnecting cause the crackling, or is it the crackling that causes the modem to disconnect/reconnect?

The Netgear router as supplied by Plusnet usually takes up to 5 minutes to reconnect to the Internet (I don't reboot it). Sometimes it is a little quicker.

I don't have another suitable router to try. Could an intermittently defective router possibly cause this issue?

My internal wiring has been visually checked a number of times by various BT engineers, & was actually reconnected by BT during the original FTTC installation, but I am not aware that it has been tested using any electronic "devices".
The filtering at the master socket should eliminate any potential issues from my own connected equipment/wiring anyway, shouldn't it?

I still await feedback from Plusnet regarding the next step(s) to resolve this.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 23, 2011, 11:09:46 AM
Hi Paul,

You might try gently moving all the components whilst listening on the phone. You could also suggest the next engineer replaces the socket components and replaces the modem RJ11 cable, just in case.

{VOIP modems (Where you plug a phone directly into the modem) are the only ones that I know of that have a relay inside which you usually hear click during the power up sequence.}

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on August 23, 2011, 11:38:14 AM
Hi Baldeagle1,

Your line is configured for a maximum speed of 22.4Mbps currently but the modem is only achieving approximately 12Mbps.  I've set the ball rolling for a broadband engineer to visit as per the previous telephone engineer recommendation.  If you can update your support ticket with date and times of availability i'll get this booked for you.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 11:44:38 AM
Thanks Alex,

Will do.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 23, 2011, 11:54:13 AM
"Configured to a maximum of .....". Surely this configuration (Capping ?) needs removing now the attenuation issue has been resolved. It was that which was the absolute major contributing factor, to only having a max possible connection of 22/23 Meg. The attenuation is back to what it should be, and therefore the DSL should be reset to default inorder that BE gets his full whack back.

Walter, we don't fault to component level anymore, haven't done for over 20years. If the socket is faulty, the whole thing will be changed out.

We will only change the RJ11 lead if a 'Boost' task has been raised against the fault. The 'Boost' tasks are currently dominated by BTr, but I believe Plusenet and Sky are either coming on board, or are on board but I haven't had a task from them yet ?? With the 'Boost' tasks, we are allowed to replace the Hub/Router and associated leads. With bog-standard SFI tasks, we only work to the socket.

BE -- your question wasn't "Silly" as this method was employed over the years on POTS lines over a certain distance.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 23, 2011, 11:56:18 AM
FYI, I have only ever noticed the crackling following the modem's disconnection, during the reconnection process (I do keep having a quick listen at other times).

As soon as the modem reconnects (reasonably quickly), the crackling immediately stops.

That is interesting and requires investigation. If at all possible, when a disconnection (loss of sync) occurs could you very quickly disconnect the Netgear router, as well as listening on the phone? If no crackling has been heard by the time the modem has re-established sync with the cabinet's DSLAM, then the Ethernet cable between the modem & the router and the router itself should be checked.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 12:07:01 PM

"Configured to a maximum of .....". Surely this configuration (Capping ?) needs removing now the attenuation issue has been resolved. It was that which was the absolute major contributing factor, to only having a max possible connection of 22/23 Meg. The attenuation is back to what it should be, and therefore the DSL should be reset to default inorder that BE gets his full whack back.


Cheers razpag.

Unfortunately I have no idea what effect the removal of the double jumpering had on my attenuation level(s).

I will have to wait for the broadband engineer's visit to discover that.
Wouldn't it have been really, really, really, really useful to have checked it immediately after yesterday's work?
If only all engineers carried a JDSU, or similar device.................

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 23, 2011, 12:12:34 PM
If only ...........

2 small words.  ;D

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 23, 2011, 12:36:59 PM
@ RP, Thanks very much.

@ Paul, What a brilliant idea it would be if the EU had access to the modem's stats !!!!!!!!! That might even reduce the number of expensive JDSU engineers' site visits, as well as being able to report that data directly back to PlusNet.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 12:39:57 PM
@ RP, Thanks very much.

@ Paul, What a brilliant idea it would be if the EU had access to the modem's stats !!!!!!!!! That might even reduce the number of expensive JDSU engineers' site visits, as well as being able to report that data directly back to PlusNet.

Kind regards,
Walter


Hahaha Walter,

you just beat me to it.
I just logged back on to add that wild, crazy, obviously stupid idea :lol: :lol:

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 05:47:24 PM
Quick Update Gents:-

BT has arranged for an engineer to check my line already, but will not have to visit the premises at this stage.  The lead time for this task is 24 hours. 
Plusnet's Alex will check up on this tomorrow and if there are no further updates he'll go for a site visit engineer.

I notice we are on forum page 14 already.
Hopefully not many more to add now, apart from the one stating SUCCESS.

Paul


Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: UncleUB on August 23, 2011, 06:35:48 PM
Quote
I notice we are on forum page 14 already.
Hopefully not many more to add now, apart from the one stating SUCCESS.

Paul

I think you are well on the way to a best seller here  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 23, 2011, 06:51:02 PM

I think you are well on the way to a best seller here  ;D


As  long as it ends up with "and they all lived happily ever after" :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 24, 2011, 03:34:47 PM
Dear Readers,

Just a quick update.

It seems like there has been a slight misunderstanding regarding PSTN/Broadband engineer tests/visits etc.

Alex from Plusnet has today confirmed that a FTTC3 Engineer will now be carrying out some line tests & visiting my home, with a view to restarting the DLM "at the full 40 Mb" on Friday morning.

Following the 2 separate PSTN engineers' visits on Monday, it would appear the "broadband engineer" tests (not requiring a home visit) that I understood were arranged for today, will now be combined in Friday's home visit. 

I am still slightly convinced that my line has only been partially fixed (by removal of the double jumpering on Monday), as I still experienced a disconnection/reconnection, crackly phone line, & drop in IP Profile to around 12 Mb an hour or so AFTER its removal.
At least my line attenuation should now have reduced substantially, & may now even be in balance regarding downstream & upstream readings from the JDSU.
This will be revealed on Friday. The camera is fully charged & ready for action.

FYI, I had to turn all my power off for a few minutes last night while I carried out a bit of unassociated rewiring work.
Apart from that, my connection has been stable, but slow, & my phone line has been quiet.

On switching it back on, my IP Profile immediately jumped up, from the 12 Mb that it had dropped down to following Monday's work, up to 20 Mb.
This "appears" to suggest that end-user intervention is sometimes required following re-syncing events that are outside the end-user's control.
This goes completely against all the advice that modems should be left switched on 24/7 for DLM to take care of things?
It also seems to suggest that DLM initiated IP Profiles can actually get "stuck".

Stay tuned folks.
More updates on Friday.

@ razpag,
Just for curiosity, do you know if there is a "reset" button, or a laptop interface in the actual FTTC cabinet for resetting DLM back to the full whack for individual connections?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 24, 2011, 05:58:50 PM
Dear Readers,

Just a quick update.

It seems like there has been a slight misunderstanding regarding PSTN/Broadband engineer tests/visits etc.

An FTTC3 Engineer will now be carrying out some line tests & visiting my home with a view to restarting the DLM "at the full 40 Mb" on Friday morning.

Following the 2 separate PSTN engineers' visits on Monday, it would appear the "broadband engineer" tests (not requiring a home visit) that I understood were arranged for today, will now be combined in Friday's home visit. 

I am still fairly convinced that my line has only been partially fixed (by removal of the double jumpering on Monday), as I still experienced a disconnection/reconnection, crackly phone line, & drop in IP Profile to around 12 Mb an hour or so AFTER its removal.
At least my line attenuation should now have reduced substantially, & may now even be in balance regarding downstream & upstream readings from the JDSU.
This will be revealed on Friday. The camera is fully charged & ready for action.

FYI, I had to turn all my power off for a few minutes last night while I carried out a bit of unassociated rewiring work.

On switching it back on, my IP Profile immediately jumped up, from the 12 Mb that it had dropped down to following Monday's work, up to 20 Mb.
This "appears" to suggest that end-user intervention is sometimes required following re-syncing events that are outside the end-user's control.
This goes completely against all the advice that modems should be left switched on 24/7 for DLM to take care of things?
It also seems to suggest that DLM initiated IP Profiles can actually get "stuck".

Stay tuned folks.
More updates on Friday.

@ razpag,
Just for curiosity, do you know if there is a "reset" button, or a laptop interface in the actual FTTC cabinet for resetting DLM back to the full whack for individual connections?

Paul.

Hi Paul

Firstly, apologies for not getting back to you sooner (RE- the PM), have had a busy personal life this last 2 days/nights. So, having read your latest post, I wont need to respond to the PM mate.

To answer your question on the last paragraph in your post ..... no there isn't. It will most likely (IMO) be a case of BTw 'rebuilding' the DSLAM remotely, or, a 'Lift & Shift' ??. I've no idea Paul, as I don't know what measures Openreach, BTw and Plusnet have agreed to ??

To cover another statement made within your post. You've only re-synched back at 20Mb as you've in forced a 'Power cycle' by turning the Hub off whilst working on your electrics. The DLM will still take this back down to 12Mb over an ammount of time if you still have a fault present. Constant turning on and off of a Hub/Router that is under DLM (RAMBo), especially 21CN products has nothing but a detrimental effect for the vast majority of circuits. TBH, this is going slightly off topic as there is another thread somewhere where this has been debated.

Another issue you had was, "What is an FTTC3 Engineer ??". Honestly ??, I haven't the foggiest Paul. Never heard that terminology used within OR.

Fingers crossed yet again for Friday mate. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 24, 2011, 06:28:41 PM
@ razpag,

No worries re the PM. Due to the "misunderstanding" it didn't matter anyway.

I was that keen to not turn off the modem, I nearly did the wiring without turning off the power.
Remember what it was like before health & safety was invented?
It was too dark though.

Apparently, a type 3 engineer is "broadband", a type 1 engineer is "PSTN".
I think a type 2 engineer is the one that brews up & goes to the greasy spoon for the bacon butties.
These must be Plusnet's own terms if you have not heard of them before.

I can't wait to see the JDSU readings on Friday. I'm getting all excited just thinking about it.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 24, 2011, 06:47:52 PM
Ha ha ha ...... me and a dozen others too I would think Paul. Might take a days A/L and come to yours on Friday ??  ;) ;D

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 24, 2011, 06:55:29 PM
Ha ha ha ...... me and a dozen others too I would think Paul. Might take a days A/L and come to yours on Friday ??  ;) ;D

You're genuinely welcome any time between 8am & 1pm.
OMG, that sounds like a bloody BT appointment :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 24, 2011, 06:58:40 PM
Ha ha ha ...... me and a dozen others too I would think Paul. Might take a days A/L and come to yours on Friday ??  ;) ;D

You're genuinely welcome any time between 8am & 1pm.
OMG, that sounds like a bloody BT appointment :lol:

 ;D You could print tickets, judging by the ammount of interest on here Paul !!

'Bald Eagle's 35Meg surprise party. Bring your own JDSU's.'      ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 24, 2011, 07:09:56 PM
 ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 24, 2011, 07:15:29 PM
Clever beggar !!! LOL.  ;D ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 24, 2011, 07:58:09 PM
I'll come! :drink:

Especially as I am now the owner of a 301C. :dance:

Completely OT but does anyone else appreciate the look of this piece of antique GPO test equipment that I discovered for sale on eBay?

http://www.ebay.co.uk/itm/130563649602?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

The current bid of £0.01 was not made by b*cat. :P
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 24, 2011, 08:09:29 PM
What do you mean ....... antiquated ???  ;D

There's still odds and sods of the old-style testing equipment, knocking around various exchanges. I have to say though, i've never heard of a stand-alone PBX tester ?? The old 'Test Desk' (as in a desk and not a unit like the image on e-Bay) used to perform a myriad of functions, including PBX tests. I thought all testing was incorporated within the Test Desk ??

Not my forte at all though, as I only had perhaps 4/5 yrs of experiencing the old Strowger/Crossbar/TXD/TXE exchanges.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 25, 2011, 06:50:03 PM
Ee by 'eck,

I'm all of a tither that I'll get back my "Good Honest Broadband From Yorkshire" tomorrow.

TBH, it's the bit delivered through Oldham's suspect cabling that I'm bothered about  :no:

Progress update tomorrow folks.

The champagne's on ice, just in case.

Paul.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on August 25, 2011, 07:44:10 PM
Hi
quote : This goes completely against all the advice that modems should be left switched on 24/7 for DLM to take care of things?
You don't mention your SNR margin .
If your   last resynch was done during a noisy period then your synch rate would have been lower than optimum synch  for your (target) snr margin and attenuation  . If the noise decreased allowing your SNR margin to go up then you manually resynching would result in an increase in synch rate with the (target) Snr margin applied by the DLM .
This situation is not normally resolved by the DLM .

 quote It also seems to suggest that DLM initiated IP Profiles can actually get "stuck".

Don't know bout 21cn but yes its possible
http://www.kitz.co.uk/adsl/IPprofile.htm

Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 25, 2011, 08:30:08 PM
Hi
quote : This goes completely against all the advice that modems should be left switched on 24/7 for DLM to take care of things?
You don't mention your SNR margin .
If your   last resynch was done during a noisy period then your synch rate would have been lower than optimum synch  for your (target) snr margin and attenuation  . If the noise decreased allowing your SNR margin to go up then you manually resynching would result in an increase in synch rate with the (target) Snr margin applied by the DLM .
This situation is not normally resolved by the DLM .

 quote It also seems to suggest that DLM initiated IP Profiles can actually get "stuck".

Don't know bout 21cn but yes its possible
http://www.kitz.co.uk/adsl/IPprofile.htm

Regards Jeff


Cheers jefbb,

Page 15 already. I really hope we don't end up filling up any more pages.
There should still hopefully be room on page 15 for me to report a successful outcome tomorrow.

One of the problems is that we just can't see our connection stats so I have absolutely no idea what my SNR & attenuation levels are at any given time.

I have read that a resync during daylight hours is preferred as lines typically become "noisy" in the evenings.
However, my own limited experience with FTTC is that (for whatever reason) whenever the modems have resynced in the evenings, the speeds have been higher than when resyncing during daylight hours.
This also appears to contradict current advice.

By far, the vast majority of resync events have not been initiated by me.
Plusnet have advised me to hang on for 10-14 days & the speeds should increase automatically via DLM, assuming the line is stable.

The fact that the various modems have been incapable of hanging on to a connection for that length of time (apart from the first couple of weeks), seems to clearly suggest a line instability issue that just needs "fixing".
Monday's engineers thought they had tracked it down & "fixed" it.
Whenever I have checked my phone line recently, at the same time the modems are attempting to automatically reconnect following an uninitiated disconnection, I have heard the crackling on the phone (even since Monday's "fix").

Just as an experiment, I turned off the modem today for a few minutes then turned it back on again, whilst listening to the phone.
All the way through to being able to browse the internet again, the phone was completely silent.
However, my IP profile dropped from over 20 Mb back down to less than 15 Mb. That was around lunchtime.

There is a known issue with the BT modems overheating & being unable to maintain connections.
In my case, I believe this known issue may have mis-led both Plusnet & BT into thinking the modems have been the problem.
I have told them on a number of occasions that any modems I have used have only ever felt "a bit warm", definitely not hot.

Hopefully all will be revealed tomorrow when BT will be testing "everything" & resetting my profile to the full 40 Mb.
Going off when FTTC was first installed, I would expect around 35 Mb (ish) by the time it reaches my house after travelling for around 820m or so.
If nothing else, I will be able to obtain my connection stats from the engineer's JDSU & compare them with the last time they were obtained.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 08:56:17 AM
Engineer arrived.

Won't let me get the JDSU stats. Reckons he would get sacked if he showed me, never mind a photo.

Gone to Cab to check for 40 Mb

Only 22 Mb at home (verbally only from the engineer)

PQT & everything O.K.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 26, 2011, 09:33:29 AM
Hi Paul,

Surely it's necessary for somebody to reset (Possibly retrain ?) the service to allow the full speed?

Assuming you still see 22 Mb isn't that about the speed limit that Plusnet have said the service was configured to provide at present ?

It's rather disappointing that the BT Engineer believes he's not allowed to disclose the data to demonstrate the performance of the service you are paying for.

EDIT :- However I believe that the JDSU uploads the test results to a BT database when a connection is available so all is not (yet) lost. All you now have to do is request that PlusNet provide you with that data so you can monitor the condition of your service adequately. Given that this data is quite freely available on all other types of ADSL, I cannot believe that FTTC service performances are commercially secret. I know that ISPs have always, up to now, been allowed to give you the engineers' visit reports data.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 11:50:15 AM
Right, I'm back online again, but I haven't cracked open the champagne just yet.

On arrival the engineer confirmed that nobody had informed him of the issues history or previous visits.
So I gave him a very quick summary.
He also confirmed he could stay as long as it took to sort this issue out.

The engineer visually checked my internal wiring - all O.K, apart from one plug on one of my telephone extensions.
He said it needed a quick clean as it could potentailly cause a problem.

He plugged in his JDSU & laptop, but point blank refused to let me look at them.
He said he was only allowed to give me any stats verbally & there was no way he was going to risk being sacked for letting me see them.

Is that really the case razpag, that BT intentionally hide from end users the statistical details of the service that they are actually paying for, & that engineers can be instantly sacked for allowing users to see the stats?

We already know that the user interface for obtaining connection stats has been intentionally locked/hidden in the BT supplied modems.

He also added that strictly speaking, he should only be confirming whether or not speeds were higher than BT's minimum of 15 Mb.

Verbally obtained stats:-

Downstream Max Rate - 22 Mb
Downstream Actual Rate - 19.2 Mb
Downstream Line Attenuation - 23 dB (this is down from the 30.2 dB that I was allowed to photograph last time, but is it good or bad?)

The engineer stated that the attenuation value takes the whole telephone line from the exchange into account & not the distance from the cabinet.
Again, razpag, I suspect your findings from your recent installation job would confirm otherwise.

SNR - 5.7 dB (down slightly from 5.9 dB last time)
PQT - O.K.
REIN - O.K.
Line Length - Wouldn't confirm - said the JDSU does not report it. (I'm sure I have seen a photo somewhere of a JDSU showing line length)
Line generally is O.K.

He said that the results would be emailed immediately to Plusnet from his laptop, but he was not allowed to actually speak to them.

Off he went to the cabinet & I saw the modem disconnect.
Quite a while later he phoned me to say he had found that the speed was only 22 Mb at the cabinet. Hence me only receiving that speed at home.
I suppose that confirms that the D-side line is currently good enough to get whatever the cabinet is able to throw at me.

He also mentioned that had been unable to locate any faults on the E-side.

He went on to say he had been on the phone for ages to BT explaining the position & to request a "port flex".
I have never heard that phrase before & the engineer wouldn't expand other than to say it is not a "lift & shift".
I can only assume for now that is his terminology for a resetting of my profile and/or resetting DLM back to the starting point.

razpag, are you able to expand on what this actually means to BT?

He said I should get my fast speeds back anywhere within a few minutes to 24 hours from now as my line is good enough to support "quite a lot more" than the current 22 Mb.

This is the current speedtest.net result:-
(http://www.speedtest.net/result/1451004133.png) (http://www.speedtest.net)

The engineer did also mention that a lot of major wire & fibre cabling work is going on in Oldham Town Centre to make way for a new tram system (Metrolink) & this could potentially be causing a number of disconnections/speed issues for any number of Oldham's residents.

It seems like I will have to play the waiting for a while longer.

Alex from Plusnet has requested feedback from today's visit. Once I have updated him I will post any confirmation of what happens next on here.
It may be the case that Plusnet now have to nudge something at their end as was the case when FTTC was initially installed.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 26, 2011, 01:09:08 PM
Dinner break so quick reply.

Port flex in its basic terms means removing 'cappings' or other stuff to take back to default settings, ie-40Meg. Its a switch on-switch off in it's crudest form.

I mooted about checking for 40Meg at the PCP in my PM to you this morning, hence the other stuff about not being 'rocket science'. As I've said before, the int. crackle you have is so intermittent it wouldn't affect your speeds, maybe give a tiny few errors, but thats it.

Why it's taken so long to find a 'double jumper' in the Cab (the crux of all the problems), and the fact the DSLAM Port has locked up, is incredulous !!!

It can take time to 'flex' the circuit by a manual controller, so give it 24 hrs mate, but after that get on to them again. They may have 'flexed' and nothings happened. Then it needs a 'Lift & Shift'. Good days are on the horizon.

PS-- the engineer is wrong IMO, I always show the EU their stats if they're interested, there is nothing to hide ??Plus, nothing has ever been said that I've seen documented to say otherwise. I can't blame him for being cautious though, they tin-tack folk for 'owt these days. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 01:25:32 PM
Thanks razpag,

You have answered a couple of my queries there.

I am still awaiting feedback from Alex at Plusnet, especially my actual stats from this morning.
He is apparently not in work at the moment.

The Plusnet guy I spoke to confirmed that at their end, I am currently on, & have been since FTTC was installed, their max profile (for some reason they call it 37 Mb for all FTTC users).

I just await with bated breath for BT to do their bit now.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 04:23:02 PM
Anyone fancy making any sense of the attached document & relating it to the UK's FTTC service via BT?  :no:

It talks about Attenuation & SNR etc.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 26, 2011, 04:53:29 PM
Not sure what info you need other than what is in the doc Paul ??? It is what it is.

My only comment to add to that document is, that the real issue is noise. If noise were completely erradicated, we could get 100Mb over 0.5 Cu cables. The blindingly obvious problem is this total elimination, hence the earlier comments withing the document about cat cable (more twists) being better at removing noise ceilings.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 05:53:42 PM
@ razpag

Edging toward total geekiness, all I was trying to suss out was what sort of attenuation I should expect for my own line length, or conversely what line length I should expect for my own attenuation as verbally reported today.

Your example of a recent installation was that the attenuation at the home was 13.5 dB over a known line length of 488m.
Entering 13.5 dB into the Kitz ADSL calculator results in a line length of 900m (more or less double the actual length). However, more or less the full 40 Mb was still delivered to the home speed-wise.

As the formula in the document uses frequency as part of the equation, I was hoping someone could confirm the frequencies used for the various flavours for ADSL, along with the frequency used for FTTC as provided by BT.

I have been unable to determine the actual frequency used for FTTC in the UK, but I believe BT use the 8c frequency profile.

Depending what I read, the frequency could be 4 MHz or 7 MHz for BT, & as high as 30 MHz in other parts of the world?

My current attenuation of 23 dB entered in the Kitz calculator results in a line length somewhere around 1700m (again double the real length).

From last time's JDSU attenuation reading of 30.2 dB, it resulted in a line length of 2200m.

I appreciate that SNR has a large bearing upon achievable speeds, but so too do attenuation/line length.

I just want to dispel once & for all the theory that BT & Plusnet both appear to have in that I have a very long line length from the cabinet (just in case they use that argument against me yet again in my ceaseless quest to regain my prevous higher speeds).

It may also even be useful for others at some stage, such as the guy in the other thread
( http://forum.kitz.co.uk/index.php/topic,9846.0.html ) who currently has a reported attenuation of 63.5 dB (probably really more), just in case he should be considering FTTC as a possible option to increase his throughput speeds.

using an attenuation of 13.81 dB/km as the default constant for 0.5mm wire & 4.3 MHz as the frequency tells me that my line is pretty near perfect attenuation-wise for the known distance or pretty near 850m in length for the known attenuation.

Of course I may have used completely wrong values, hence my query, meaning my attenuation could be still pretty poor for the known distance.


EDIT:

OMG we are nearly on page 16 now.



Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 26, 2011, 06:20:15 PM
I see Paul. You have well and truly got the 'Broadband bug' mate. :lol:

My "Example" if you re-read, has me saying the actual attenuation would more likely be 11dB for the EU, as the JDSU is 'resistance heavy' and always 'add's a few dB's onto the figure.

Regarding the transmission frequencies ?? No idea mate, i'm sorry. Maybe when we get FTTC round my way, and there's more work than the squaddies and wet-behind-the-ear prenny's can handle, I might be able to enlighten further ?? Will you still be frequenting Kitz in 2-3 yrs time Paul ?? ;)

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 06:57:35 PM
I see Paul. You have well and truly got the 'Broadband bug' mate. :lol:

My "Example" if you re-read, has me saying the actual attenuation would more likely be 11dB for the EU, as the JDSU is 'resistance heavy' and always 'add's a few dB's onto the figure.

Regarding the transmission frequencies ?? No idea mate, i'm sorry. Maybe when we get FTTC round my way, and there's more work than the squaddies and wet-behind-the-ear prenny's can handle, I might be able to enlighten further ?? Will you still be frequenting Kitz in 2-3 yrs time Paul ?? ;)

Even at 11dB, the Kitz ADSL calculator comes up with 800m, & I was going from memory, which I have to admit isn't quite what is was a few years ago :(

FTTC frequencies anyone?

Will I still be frequenting Kitz in 2-3 yrs time?
No, I'm buggering off & leaving you all in peace as soon as I get my 33 Mb back :lol:, unless it takes 2-3 years to get it back again.

Actually, I have been frequenting Kitz for a number of years (unregistered). I have found it to be a really useful & well informed resource (mind you when you only expect 1 Mb & actually get 1 Mb most of the time, there's not really a lot to consider is there?)

I have a feeling that I might just hang around & maybe find the opportunity to give back some of the excellent & friendly advice that you have all found the time to offer me, without all the nonsense that some forums (fora?) contain.

You know what I mean; "My sky box is connected to the toaster through a wireless cable & the front tyre on my mate's car is flat, what broadband speeds should I expect?" ???


Paul
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 26, 2011, 07:02:11 PM
What about this for a recent download speeds graph?

Isn't it supposed to be something like a straight line?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 26, 2011, 07:06:41 PM
Ha ha ha, cracking up at your last line. :lol:

Why not start a thread on, 'Improving your homes structural well-being' ?? I've questions like "Is a 'raft' better than 'piling', and other such queries.  ;D   
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 26, 2011, 07:38:23 PM
Quote
You know what I mean; "My sky box is connected to the toaster through a wireless cable & the front tyre on my mate's car is flat, what broadband speeds should I expect?" ???

Answer: A sack of onions. ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 26, 2011, 08:45:52 PM
@ BKK,

Are you implying that it's a total sack of sphericals ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on August 26, 2011, 08:50:42 PM
@Walter -- Do you also perform mind readings at various Surrey village shows? "Spherical obloids" is the appropriate phrase. ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 27, 2011, 08:53:15 AM
21 hours back online since yesterday's engineer's visit & no change to speeds yet.

Not that I'm watching the clock or anything :D

My spreadsheet is doing that for me, to the nearest second - GEEK!!!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 27, 2011, 01:39:26 PM
Dear readers,

Well, the 24 hours have been & gone & still no improvement or feedback from anyone at Plusnet or BT.

I suppose I will have to wait until sometime next week now as it's a Bank Holiday on Monday.

At least the line "appears" to be stable now.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 30, 2011, 12:01:02 AM
No news is good news?

No unforced disconnections since Friday.

The line seems stable & no audible crackling on the phone.

Hopefully, the next step(s) will be instigated on Tuesday (whatever they are).

At least I've managed to get some plastering & plumbing done in the meantime.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on August 30, 2011, 12:49:06 PM
Hi Bald_Eagle1,

Your support ticket has been updated.  As per the ticket we will need to monitor the line over the next 24 hours to allow the DLM reset to complete which the engineer initiated.  I will contact you tomorrow if any further action is required.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 30, 2011, 01:01:01 PM

Your support ticket has been updated.  As per the ticket we will need to monitor the line over the next 24 hours to allow the DLM reset to complete which the engineer initiated.  I will contact you tomorrow if any further action is required.


Thanks Alex. Fingers crossed  ;)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 30, 2011, 06:05:20 PM
Walter, Mr Eagle and B*Cat ......... had half a FTTC job today  ;D. Ended up as a 'No access'.

Anyhows, whilst at the Cab, I thought I'd take the attenuation reading before and after the dial tone had been put through to the DSLAM. Results ?? The attenuation was exactly the same.

Therefore, any attenuation readings taken from the EU's premises back towards the Exchange, only account for the D-side network. HTH in future investigations for the EU's and any ISP's looking on. ;) ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 30, 2011, 06:48:44 PM
Hi RP and thanks for using your time so effectively !

That does perhaps make some sense as the attenuation observed is presumably part of the synchronisation process between the DSLAM and the EU's modem. Did you by any chance monitor the SNR as well ?

However I'm unclear what this means for Paul as his attenuation figure seems far too high for a normal twisted pair run of about 800 m (as obtained from the BT O records) between his house and the PCP. If I'm not mistaken RP you've said an 800 m line distance might be expected to have VDSL2 speeds far closer to the maximum than Paul's service provides now.

(I'm also perplexed as to how DLM settlement is expected to increase the sync speed by a significant amount when I believe Paul says his bRAS is 21,166 Kbps now when he had observed far higher figures before?)

“Curiouser and curiouser!” Cried Alice !!!!

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 30, 2011, 06:57:03 PM
Hi RP and thanks for using your time so effectively !

That does perhaps make some sense as the attenuation observed is presumably part of the synchronisation process between the DSLAM and the EU's modem. Did you by any chance monitor the SNR as well ?

However I'm unclear what this means for Paul as his attenuation figure seems far too high for a normal twisted pair run of about 800 m (as obtained from the BT O records) between his house and the PCP. If I'm not mistaken RP you've said an 800 m line distance might be expected to have VDSL2 speeds far closer to the maximum than Paul's service provides now.

(I'm also perplexed as to how DLM settlement is expected to increase the sync speed by a significant amount when I believe Paul says his bRAS is 21,166 Kbps now when he had observed far higher figures before?)

“Curiouser and curiouser!” Cried Alice !!!!

Kind regards,
Walter

Walter ...... thanks for you comments. You see I do think about you, even when I'm not on here.  ;D

I can't remember the D-side distance I quoted on the FTTC Install I did the other week, but I'm sure it was less than 800mtrs Walter ?? Thought it was around 400-500 mtrs ?? Whatever, the synch speed was exactly 39.9Meg on that particular line and I hoped to give a wee bit of guidance in relation to Baldy's line length.

I too am like you and feel time is being wasted with regard to the DLM. The engineer stated he only got 20-odd meg at the DSLAM, then either a full port/card reset is needed, or a lift and shift carried out. DLM will not get any higher without this.

Glad you said it and not me Walter !! Didn't want to upset Baldy any more than what he is. :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: renluop on August 30, 2011, 07:45:46 PM

Glad you said it and not me Walter !! Didn't want to upset Baldy any more than what he is. :lol:
He having been balded, I have been wondering where his other feathers were being plucked from :-\ :o ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 30, 2011, 09:10:34 PM
Evenin' All,

Rather than respond individually, I'll just provide an update.

Plusnet's Alex has confirmed he has discussed this case with BT who advised him that the line had been Port Flexed and the DLM system reset.

He also confirmed the Port Flex is simply a reset of the broadband port I am connected to in the cabinet. The DLM reset is a reset of the DLM system which controls my line.

The BT agent asked Alex to monitor my line for the next 24 hours to allow the DLM reset process to complete and to get back in touch with them if my speed has still not improved. He will re-check this tomorrow and take any further action needed if required.

Well, my IP Profile (bRAS) is now 24244 k.

It was at that level when one of the engineers requested a profile reset some time ago.
However, shortly afterward it dropped back to around 15000 k.

I do hope the improvement from around 22Mb to 24.2 Mb is not classed as a suffient improvement to avert any further action.

A property less than 100m across the road from me has estimated FTTC speeds of 27.9 Mb downstream based upon speeds achieved by consumers in the area.
I believe I was that consumer as my download speeds were stuck at that level for a while shortly after the start of the gradual decline.

Touch wood, my line now appears stable with no unforced disconnections or crackly phone lines.

We now have absolute confirmation that attenuation values for FTTC only take into account the D-side line between the end user & the cabinet (as suspected all along - despite what my latest visiting engineer stated).
The only thing I don't have is a record of my line's attenuation from when it was achieving higher download speeds, to use as a comparison with the recent verbally reported value of 23 dB.

From what have gathered about FTTC, it appears that higher speeds can be expected up to a distance from the cabinet of around 1200m. Thereon, speeds tail off dramatically, no doubt due to the different frequencies used for FTTC, resulting in higher attenuations than for the same line length being used for ADSL.
I have also gathered that FTTC download speeds are usually a lot closer to the bRAS than is the case with ADSL - maybe quite a bit over 90% compared to around ADSL's 85%.

What I don't know is whether or not my current attenuation of 23 dB is about right for my distance from the cabinet of around 820m.
If it is, I very strongly suspect it must also have been around 23 dB when I was achieving higher speeds.
If my attenuation is currently substantially higher than when FTTC was installed, there must still be a problem with the D-side that wasn't present for the first couple of weeks following installation.

Plusnet have previously confirmed that no records exist from the original installation & I only started keeping records following my speeds suddenly dropping from 33 Mb to 27-28 Mb. At that time I thought a 5 Mb drop was a problem!!

razpag recently quoted a line length of 488m when obtaining a JDSU attenuation reading of 13.5 dB & speed of 39.9Mb. The next time he installs FTTC on a line length of 820m. I just know he will be bursting to confirm the attenuation & SNR values in this thread ;D. It will address so many questions in one hit.

So, will my speeds improve significantly over the next 24 hours via DLM?
They have not done so previously, so I suspect not.

Is a bRAS (IP Profile) of 24 Mb now correct for my line?
Not if it has achieved much higher speeds in the earlier days.

What else needs to be physically done to get my connection back to the equivalent of a brand new installation with 40 Mb at the cabinet?
Possibly a simple lift & shift?

Has my speed been capped via DLM due to all the disconnections & crackly phone line over the last 2 months?
Probably, but what is now causing my profile to be "stuck" - faulty electronic equipment in the cabinet or at the exchange?

Why are we continually going over the same ground?
Can it really be a simple lack of knowledge of how FTTC actually operates?
The various engineers who have visited my home all appear to have a slightly differing take on matters, so maybe it is.
Plusnet also previously admit they are not too sure either.

What's with all the "Baldy" references already :lol:?

I'm not saying where the other feathers were being plucked from other than to say I don't need all 3 from the back, crack, & sack wax treatment ;) :lol:

More news tomorrow folks.
I already have it typed out - "Success - 35 Mb bRAS, 32-33 Mb downloads back again" :no:

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 30, 2011, 09:32:29 PM
Quote from a page or two ago, "Quite a while later he phoned me to say he had found that the speed was only 22 Mb at the cabinet".

A 'port flex' should have reset this back to 40Meg. If it hasn't, the port is more than likely faulty. Your speeds are still very similar to when you were 'double jumpered' at the Cabinet, therefore it would suggest that the port hasn't reset back to default 40Meg ??

The only variable we don't know, is the length of the stray 'double-jumper' ?. If it was connected to your D-side as mentioned by the engineer, but the other end was hanging loose (not chill-axeing  ;D) only a few feet away within the Cabinet, then the 'extra attenuation' would be negligible. If the other end was connected direct to another E-side or D-side, then the attenuation would quite substantial.

The only definitive way of knowing what your line is capable of, is to have an engineer 'see' if your port is giving out 40Meg at the FTTC.

Regarding 'records'. I'm sure BTw would have a record on RRT of your 35Meg connection rate from their 'Baseline' data stats. I wouldn't know how you could retrieve these though ?? I would think only your ISP, or an engineer working on a 'live' fault would be able to glean that info from them.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 30, 2011, 10:01:52 PM
Quote from a page or two ago, "Quite a while later he phoned me to say he had found that the speed was only 22 Mb at the cabinet".

A 'port flex' should have reset this back to 40Meg. If it hasn't, the port is more than likely faulty. Your speeds are still very similar to when you were 'double jumpered' at the Cabinet, therefore it would suggest that the port hasn't reset back to default 40Meg ??

The only variable we don't know, is the length of the stray 'double-jumper' ?. If it was connected to your D-side as mentioned by the engineer, but the other end was hanging loose (not chill-axeing  ;D) only a few feet away within the Cabinet, then the 'extra attenuation' would be negligible. If the other end was connected direct to another E-side or D-side, then the attenuation would quite substantial.

The only definitive way of knowing what your line is capable of, is to have an engineer 'see' if your port is giving out 40Meg at the FTTC.

Regarding 'records'. I'm sure BTw would have a record on RRT of your 35Meg connection rate from their 'Baseline' data stats. I wouldn't know how you could retrieve these though ?? I would think only your ISP, or an engineer working on a 'live' fault would be able to glean that info from them.

I suspect a visit to the cabinet to check speeds there will have to be the next step, possibly requiring another home visit to check speeds at the master socket.

To help me understand clearly, when speed is checked for 40 Mb at the FTTC cabinet, is it done before (E-side) or after the DLM equipment (D-side), or both?

Somewhere in the equation is the capping of upload speeds (2 Mb for my package & I currently have no problem with upload speeds, although I did have for a while - down to 0.67 Mb). Do you know whereabouts this capping is implemented?

If a lift & shift is carried out, I presume that would be in the FTTC cabinet. Would I still end up using the current DLM hardware (potentially faulty) for my connection?
Is there ever a need to do some physical work at the exchange?

 Questions, questions, questions  :D

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 30, 2011, 10:16:36 PM
Quote from a page or two ago, "Quite a while later he phoned me to say he had found that the speed was only 22 Mb at the cabinet".

A 'port flex' should have reset this back to 40Meg. If it hasn't, the port is more than likely faulty. Your speeds are still very similar to when you were 'double jumpered' at the Cabinet, therefore it would suggest that the port hasn't reset back to default 40Meg ??

The only variable we don't know, is the length of the stray 'double-jumper' ?. If it was connected to your D-side as mentioned by the engineer, but the other end was hanging loose (not chill-axeing  ;D) only a few feet away within the Cabinet, then the 'extra attenuation' would be negligible. If the other end was connected direct to another E-side or D-side, then the attenuation would quite substantial.

The only definitive way of knowing what your line is capable of, is to have an engineer 'see' if your port is giving out 40Meg at the FTTC.

Regarding 'records'. I'm sure BTw would have a record on RRT of your 35Meg connection rate from their 'Baseline' data stats. I wouldn't know how you could retrieve these though ?? I would think only your ISP, or an engineer working on a 'live' fault would be able to glean that info from them.

The speed at the FTTC is checked directly onto the DSLAM port (via a link cable from the Fibre Cab to the existing cab). As mooted above, when the E-side dial tone is put 'in circuit', there is no change to the 40Meg speed as the attenuation is (at this point in the proceedings), only from the DSLAM located in the Fibre Cab down the link cable to the existing Cab.

Capping is applied remotely by the ISP's. Currently, FTTC products offer up 2 or 10 meg Upstream connections. Capping is there for a variety of reasons ..... non-payment of bills, downloads over and beyond FUP, to maintain a stable circuit.

If a 'L&S' is performed, it will only require the engineer to re-jumper within the Cab to the new port, (or in laymans terms), to reconnect to a new pair in the link cable.

HTH.   
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 31, 2011, 12:20:36 AM

If a 'L&S' is performed, it will only require the engineer to re-jumper within the Cab to the new port, (or in laymans terms), to reconnect to a new pair in the link cable.
 

So, if I now understand matters a bit more clearly, all the pairs in the link cable are already connected to their own DSLAM port inside the fibre cabinet?
Inside the old cabinet, some/most of these pairs are not connected to anything. They may just be hanging loose?

When FTTC is installed for each customer who orders it, the engineer never actually goes inside the fibre cabinet.
He just connects one of the loose pairs in the link cable to the customers D-side inside the old cabinet.
Something stops (or should stop) some of the broadband going back down the E-side toward the exchange

If only 22 Mb was seen by my engineer at the cabinet, he really meant that only 22 Mb was showing inside the old cabinet at the end of the link cable.

Let's just say I am currently connected to DSLAM port No.1 inside the fibre cabinet via the link cable from the old cabinet.
A 'L & S' would disconnect me from DSLAM port No.1 & connect me to DSLAM port No.2.
Assuming DSLAM port No. 2 has never been used, DLM cannot have affected it & 40 Mb should be seen at the old cabinet end of the link cable.

If 40 Mb is not seen at the end of the link cable the unused DSLAM port No.2 could be faulty & DSLAM No. 3 will be tried & so on until 40 Mb is found.

In other words, it should end up just like a brand new installation giving me 40 Mb, less a few Mb for my D-side's attenuation.
The DLM should restart the training period until my now bang tidy D-side line makes it settle at let's say 35 Mb just for argument's sake.

If it really is as simple as that, the question has to be asked, why was this not tried before now e.g. when BT reset my profile a few visits ago to only 24 Mb, stating that was all my line could ever achieve?
It doesn't sound like a major and/or costly operation.

Are all the DSLAMS ports inside the fibre cabinet already "live", or do they need to be switched on at the exchange only whenever a customer orders FTTC or when initiating a 'L & S'?
In other words, is it just possible that only 22 Mb was/is being delivered down the fibre to the fibre cabinet?

If all my wittering above is a load of nonsense, I'm sure you will put me straight again (please)  :)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on August 31, 2011, 07:36:59 AM
Nail on head Paul.

Yes indeed, the ports are all pre-connected to the Fibre cab via a link cable. We (Openreach CSE Engineers) do not have access rights to the FTTC, nor do we need it.

The ports are dead until made 'live' via an order. Having said that, there may be situations where the port has been 'stopped', so voltage may be present (ie-synch can be attained) but there will be no virtual path to obtain an IP address. This might happen if an EU has had VDSL but is moving house.

As I say, I too am learning on the odd chances I get to go on these jobs. Shame this hadn't reared it's head 6 months ago, I was doing roughly 3/4 FTTC Installations a day. The problem is, as an engineer you aren't overly consumed with in-depth investigations into speed, attenuation etc ........ your main concern is the actual installation. If that makes sense ?
 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on August 31, 2011, 08:25:06 AM
Quote
e.g. when BT reset my profile a few visits ago to only 24 Mb, stating that was all my line could ever achieve
Unless Plusnet can do some arm twisting I feel the above statement could be correct.
Regardless of the connection achieved when the FTTC was first installed for what ever reason BT are now saying your line can only achieve 24Mb.
Depending on the wording of your contract you will be receiving a satisfactory (to BT) connection rate.
I hope you and the Plusnet guys are successful in your quest, but remember who you are ultimately dealing with.
My post is not a reflection on OR or anyone other than the provider of the system/line, and I don't mean Plusnet.
Good Luck.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 31, 2011, 08:49:13 AM
Nail on head Paul.

As I say, I too am learning on the odd chances I get to go on these jobs. Shame this hadn't reared it's head 6 months ago, I was doing roughly 3/4 FTTC Installations a day. The problem is, as an engineer you aren't overly consumed with in-depth investigations into speed, attenuation etc ........ your main concern is the actual installation. If that makes sense ?


@razpag,

Thanks for confirming my understanding. I now see the whole thing in a much clearer light.

I realise that as an engineer, your priority is to install FTTC & make sure it works O.K.

However, as there is currently so little real-life situation data available (connection stats etc.) that would help end users understand & manage their expectations in a realistic manner, it would be really helpful if you could find the time in your busy real work schedule to make a quick note of the JDSU stats & ACTUAL LINE LENGTH for us for your next few installation/repair jobs (whenever they may be).

I wonder if any of your colleagues would be interested in forwarding such data too.

I don't mind compiling a record that would assist me personally in reporting problems etc. & probably any others who experience similar problems, and/or avoid end users wasting everyone's time by falsely reporting "problems" that are not really a problem in that their expectations may be too high.
e.g. I would not be pursuing this matter if I had never achieved higher speeds, or if I discovered that my D-side line actually went all over the place before it reached my house & ended up as say 2000m from the cabinet.

I knew what to expect via ADSL for my D-side line from the exchange & I knew when & when not to report a problem, with some confidence that I was genuinely not wasting anyone's time.

I believe we have now finally managed to get to the crux of my particular issues.
It has been quite a slog, with many (far too many) words written in various places.

Historical, real-life data to work with could/should have made this a very simple matter, with clear indications of where the problem(s) were located at a very early stage in the investigation.

On a commercial basis, just imagine how much money BT could have saved by tracking down the "real" issues & fixing them at the outset.
ISPs would also benefit by not having to keep updating fault tickets & chasing BT for the "right" sort of engineer to fix the "right" fault.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: UncleUB on August 31, 2011, 08:53:07 AM
Quote
e.g. when BT reset my profile a few visits ago to only 24 Mb, stating that was all my line could ever achieve
Unless Plusnet can do some arm twisting I feel the above statement could be correct.
Regardless of the connection achieved when the FTTC was first installed for what ever reason BT are now saying your line can only achieve 24Mb.
Depending on the wording of your contract you will be receiving a satisfactory (to BT) connection rate.
I hope you and the Plusnet guys are successful in your quest, but remember who you are ultimately dealing with.
My post is not a reflection on OR or anyone other than the provider of the system/line, and I don't mean Plusnet.
Good Luck.

I have been thinking along the same lines having followed this epic thread with great interest.

So if BT say that 24 mb is a satisfactory outcome for your line what else can you do? Does their t&c's say up to 40mb?

I think this has been a good insight into the world of FTTC,as its relatively new and most consumers have little knowledge of all the ins and outs of it.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on August 31, 2011, 08:57:20 AM
@ Uncy,

I don't think it's only the end users who lack some knowledge or possibly experience !

@ paul,

Amen to that, but you're a better man than I Gunga Din !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 31, 2011, 09:07:15 AM
Quote
e.g. when BT reset my profile a few visits ago to only 24 Mb, stating that was all my line could ever achieve
Unless Plusnet can do some arm twisting I feel the above statement could be correct.
Regardless of the connection achieved when the FTTC was first installed for what ever reason BT are now saying your line can only achieve 24Mb.
Depending on the wording of your contract you will be receiving a satisfactory (to BT) connection rate.
I hope you and the Plusnet guys are successful in your quest, but remember who you are ultimately dealing with.
My post is not a reflection on OR or anyone other than the provider of the system/line, and I don't mean Plusnet.
Good Luck.

@ silversurfer44,

BT & Plusnet have already confirmed that 15 Mb is the contractual "fault threshold" & that as I am currently achieving in excess of that speed, there is nothing that either of tham can/will do about my current issues.

However, fair play to Plusnet (& BT), they do accept that the various issues have also been affecting the quality of my telephone communications & have been & still are pushing for a complete resolution.

It would surely also be in BT's interests, as a general PR exercise if nothing else, to demonstrate that they can actually deliver a stable "up to 40 Mb" FTTC service as a "caring provider", over their aged infrastructure, given time, & genuinely dealing with broadband "faults" as & when needed.

From what has been determined to date, it could be rather embarassing for BT if I were to publish these matters to a much wider audience.
As long as my issues are finally resolved, I will be publishing the outcome with a much more positive outlook, putting the bad experiences to get to the resolution as a learning curve for all involved (including the FTTC broadband providers).

I also realise that I am but one tiny voice in this matter & BT could very easily ignore my issues, simply re-quoting the 15 Mb minimum speed "guarantee".
However, I genuinely believe they have a real interest in resolving this matter as it may even go some way to setting the scene for similar issues going forward.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 31, 2011, 09:28:17 AM

I have been thinking along the same lines having followed this epic thread with great interest.


@ UncleUB,

Hahaha, good point :), but this thread has only been epic due to the actions/lack of actions by others (mainly BT).

They have:-

Quoted my FTTC line length as 5283m, even though that is the distance from the exchange.

Stated my line could never have achieved downloads of 30+ Mb, despite their own performace tester results confirming the contrary.

Unnecessarily replaced modems with absolutely no testing or proof that they were actually faulty.

Somehow caused me to lose my telephone & broadband services for a 4 day period.

"Stupidly" (the engineer's word, not mine) double jumpered my line within the cabinet.

Run various basic tests that would knowingly not find the relevant faults. How many users would have just accepted LTOK?

Not physically checked their own cabinet/exchange equipment for potential & probable faults.

Demonstrated their lack of understanding of their own technology (various visiting engineers and "agents" either quoting inaccuracies, and/or contradicting each other)

etc, etc, etc.......................................


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Oranged on August 31, 2011, 11:52:29 AM

How many users would have just accepted LTOK?


In respect of FTTC I would suggest not that many.

Because those users who are willing to pay for Infinity (or Broadband with Fibre) are not the average user, they are users who want/need the high spec. connection and are probably more knowledgeable than Mr/Ms AverageUser
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on August 31, 2011, 12:14:20 PM

How many users would have just accepted LTOK?


In respect of FTTC I would suggest not that many.

Because those users who are willing to pay for Infinity (or Broadband with Fibre) are not the average user, they are users who want/need the high spec. connection and are probably more knowledgeable than Mr/Ms AverageUser

Hi Oranged,

You may have a very valid point there.

My own main reason for switching to FTTC (& I suspect quite a few others too) was simply that I really do live too far from the exchange to get anything better than a flaky 1 Mb connection on ADSL1.
I have also previously tried mobile phone dongles & looked at satellite as other options.

Unfortunately mobile phone reception is also very poor at my location & satellite appears very expensive.

razpag has previously hinted at current investigations into broadband being delivered via unused channels/frequencies of digital TV.

Unfortunately, I don't get very good digital TV reception either.

I do have a nice view of all the surrounding hills though :lol: :lol:

I would guess that most of the users who switched to FTTC for the same reason that I did are reasonably happy anyway that they are now achieving "proper" broadband speeds, despite the relatively high cost.

In my case, although I wasn't fully aware of the technology involved, it felt like I had won the lottery, achieving somewhere approaching full fibre speeds (well, just over 3/4 of the full speed).

Just imagine how it feels when you have just got used to living the high life, & then have to give back the rest of your lottery winnings  :(

I also have much better/more important things to do than contributing to 17 tiresome pages so far in an online forum, along with all the time I/we have spent in researching matters. Thanks again everyone for all your help & advice.
I know; it's all my own fault for asking the initial question ::).

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 01, 2011, 09:34:34 AM
Dear Readers,

Just a quick update.

I was informed yesterday that my port has now been "flexed" & my profile reset.

Plusnet's test results from yesterday:-
GEA:
Test Outcome                   Pass
Test Outcome Code           GTC_FTTC_SERVICE_0000
Description                       GEA service test completed and no fault found .
Main Fault Location            OK
Sync Status                      In Sync
Downstream Speed             23.987001 Mbps
Upstream Speed                 1.9970001 Mbps
Appointment Required          N
Fault Report Advised           N
Profile Name                      16.2M-32.4M Downstream, Interleaving Off - 0.5M-2M Upstream, Interleaving Off
Time Stamp                       2011-08-31T05:45:0

Summary:  DLM reset complete. Line profile allowing sync up to 32.4Mbps.  Need to allow time for speed to pick up.
**************************************************************************************

I have asked Alex at Plusnet to confirm why my profile had not been reset to "20M-40M Downstream, Interleaving Off - 0.5M-2M Upstream, Interleaving Off" as promised, & that it was before any of the issues started.
I await a response.

I have also requested my connection statistics from when FTTC was installed, to compare with the latest JDSU readings.
Again, I await a response.

I was advised to allow up to 120 hours for DLM to stabilise & hopefully allow the higher speeds again.

There is very little change to my download speeds as of this morning:-
(http://speedtest.net/result/1460267670.png)

I still have the theory that DLM and/or DSLAM/Exchange port(s) may be may be confused, faulty, or "stuck" due to all the previous line instabilities (now possibly cured), requiring a port switch / Lift & Shift.

This apparently only takes a few minutes at the cabinet & a few minutes back at the exchange & as a belt & braces matter, another few minutes to check the results using a JDSU at my home.
Indeed, all-in-all probably a bit quicker & cheaper than unnecessarily swapping modems.

I have no idea why this has not been tried at this time.
Only when "everything" physically possible has been tried, in effect taking my connection back to the equivalent of a brand new installation will I/we have the full picture of what has caused/is still causing the low speed issues.

22 Mb download speeds aren't that bad in general, but they are really poor for a FTTC connection, especially one that was downloading at some 10-11 Mb quicker for the first couple of weeks.

I will be patient for a few more days, even if just to disprove the theory that DLM will eventually get its act together, & then (but hopefully not) the saga will continue, making this epic forum thread even more epic in the scale of epicness.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 01, 2011, 12:49:34 PM
Here we go again

(http://speedtest.net/result/1460639992.png)

The modem disconnected & reconnected while I wasn't around, so I couldn't check the phone for crackling at the time.

The phone is quiet now though (as per usual).

It's a bit warmer out again today.
Maybe the DSLAM overheats & not the modems?

I wonder if a faulty DSLAM could have been causing the intermittent crackling, just at the same time as the modem disconnects.

Has anyone checked the equipment in the FTTC cabinet?
Not that I am aware of.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 01, 2011, 06:49:05 PM
D'oh! That's half of what I would expect you to be achieving for download speed. Clearly there is still something wrong, somewhere. :'(

With regards to the 15 Mbps download speed, that is just an arbitrary marketing limit used by BT retail. A fibre connection that can provide >= 15 Mbps download will be called BT Infinity. A connection < 15 Mbps download will be called BT Option 3 with Fibre (or something like that!)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on September 01, 2011, 08:06:13 PM
@ BKK,

I believe it is also a contractual limit for a BT Infinity product; i.e. if you have a BT Infinity fibre connection it must achieve that limit and might be used by the supplier as a get-out clause, as indeed was mentioned in Paul's case.
IMHO it is absolutely vital that you recored your initial performance figures that you accept at start of contract. This is similar to the MTR and FTR limits on "ordinary" broadband.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 03, 2011, 07:27:22 AM
Dear Readers,

Not much change yet.

I rebooted the modem early doors this morning & download speeds have gone up slightly from last time.

(http://speedtest.net/result/1463672593.png)

My IP Profile / bRAS rate is currently 19410 k, so download speeds are running at approximately 97% of my current profile.

Dooes a lift & shift now seem like the only option remaining in order to get the full 40 Mb at the cabinet & therefore treat my connection as a brand new installation & start the DLM training again on what is now considered to be a good quality, stable, but not too short line?


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on September 03, 2011, 07:29:59 AM
I would say so going from the info on here. Can't do any harm for PN to request one can it ??!! :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on September 03, 2011, 10:34:18 AM
@ Paul,

Might it be better just to ask for PlusNet's suggestions rather than make a direct request?

@RP,

Do you know if a lift and shift task / procedure is yet defined for a FTTC solution?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on September 03, 2011, 01:10:41 PM
Walter ..... never one one, but I'd be pretty damned sure it'll be exactly the same as if the DSLAM were in the Exchange. A pone call to BTw, tests and circuit history explored, then hopefully a new port given. Quick re-jumper in the Cab. Job done. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 04, 2011, 09:36:51 AM
@razpag,

Quote:
Unfortunately, most EU's are left at the behest of the SP's and the advice they are given. I call SP's (as part of my Broadband work) most days, and am left flabberghasted at some of the conversations we have !!!. Poor training perhaps ??
http://forum.kitz.co.uk/index.php/topic,9154.msg188060.html#msg188060

Hi razpag,

I noticed your above comment in the topic linked to above.

Is it still BT's position that engineers may make direct contact with SPs?
In my reply #214 in this current thread, I mentioned that the visiting engineer had told me that he had emailed his JDSU results directly to Plusnet, but that he was not allowed to actually speak to them.

I am aware that throughout my case, communications (or lack of) between the various parties have made the whole issue perhaps a little more difficult to diagnose/determine the next step(s).
I would imagine that a simple telephone discussion could often help clarify matters much better than emails.
It certainly helps within my field of work.

e.g. I may receive an emailed repair order such as "water coming through ceiling".
I would suspect a variety of causes such as roof leak, internal rainwater or soil/waste pipe leak, concealed plumbing or heating pipework leaks etc.
A quick telephone conversation directly with the person reporting the problem usually determines whether to send a plumber, a heating engineer or a roofer to quickly expedite the correct "first time fix".


Paul.
 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on September 04, 2011, 09:50:35 AM
Aha Paul, but this is 'Telecommunications' we are talking about, not building work. One thing is certain, if 'we' (Telco's) can make it difficult, then we will.  ;) ;D

Seriously, in answer to your question. When we became ' BT Openreach', there were lots of new rules & regs enforced that restricts who we can, or cannot discuss work issues with. I kid you not, if I'm sat in the Exchange Canteen area talking to another BTo engineer, and an engineer from BT Operate walks in, we have to end the convo. I appreciate we are different LOB's and this is the reason there are 'Undertakings' about who we can disclose info to.

We had a series of CBT modules regarding this subject in the early days of Openreach, and it was so intense and rigid and the consequences for non-compliance so harsh, that I decided then that I wouldn't talk to anyone anymore. Not even my wife, so there was a plus side. ;D

In reality, it is quite a 'grey' area. However, if it states on our job that a co-op call is required, then we have no choice but to speak with the ISP, 'we' don't get paid for the job if the ISP's required modules are not completed in full.

 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 04, 2011, 10:06:02 AM

We had a series of CBT modules regarding this subject in the early days of Openreach, and it was so intense and rigid and the consequences for non-compliance so harsh, that I decided then that I wouldn't talk to anyone anymore. Not even my wife, so there was a plus side. ;D

In reality, it is quite a 'grey' area. However, if it states on our job that a co-op call is required, then we have no choice but to speak with the ISP, 'we' don't get paid for the job if the ISP's required modules are not completed in full.
 


 :lol: Hahaha - every cloud has a silver lining.

Never mind a grey area, it sounds more like a whiter shade of pale to me.
Nobody has ever fully understood what all that was about either.
Oops! Might be giving my age away a bit there  ;)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: razpag on September 04, 2011, 10:18:40 AM
Top song.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on September 04, 2011, 01:16:00 PM
@ Paul & RP,

I think we can all understand that BT O have to be seen to be separate from other parts of BT as well as the other service providers, all of who whom should be treated on an equal footing.

However we also all know that any form of broadband requires the best possible twisted pair circuit and also that the newer FTTC provision is unfamiliar territory, particularly to those untrained engineers who have legitimate access to the network for the provision of ordinary phone services. Furthermore any human intervention increases the risk of unreliability and service failure. In Paul's case there is evidence that one intervention disconnected his entire phone and broadband service and that the following rectification probably resulted in the double jumpering (which we all probably believe should never have happened whether by ignorance or human error). There is also evidence that the resulting replacement circuit (or FTTC service) does not perform as well as the original one. This situation is being hampered by the rules, processes, experience levels and discussions between the various parties involved and further hindered by reluctance caused by commercial pressures to conclude rectification works.

The big question is how do we get an adequate service restored to be at least as good as the original service ? I suspect matters need escalating both by the communications provider and the service provider. How that can be achieved is another matter entirely !

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 05, 2011, 09:59:22 AM
Dear Readers,

My port was flexed & my profile reset by BT 31st August.

It is now 5th September & there is no feedback other than to report the line "appears" stable with no crackling heard, but there is still no improvement to my download speeds.
Back on to Plusnet for the next step(s) then.

More feedback later, as & when/if it is received....................

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 05, 2011, 05:53:25 PM
b*cat has been thinking. Oh-ah-oops!, I suspect, is the response of readers of this post.

Mr Eagle would really like to know the attenuation and SNRM for his D-side copper to the DSLAM in the FTTC and, due to some "high up" decision, a block (a firewall rule, in fact) to deny access to those statistics was placed in the HG612 that is installed by OR as part of their infrastructure as CPE for all FTTC installations.

Earlier in this thread I suggested the purchase of a JDSU HST-3000C to enable those parameters to be measured. That would, even at second-hand prices, involve thousands of pounds.

Another way would be to find someone to remove the relevant firewall rule from the OR provided HG612 -- i.e. modify the HG612's firmware.

Here is the result of b*cat's ponderations. I have heard rumours that the FTTC DSLAM will adapt itself to what ever modem (within reason) that attempts to sync with it. Rather than buying an alternative VDSL modem[/router] -- as currently being documented in Walter's VDSL Modems for FTTC services (http://forum.kitz.co.uk/index.php/topic,9707.msg196127.html#msg196127) thread -- why not do a very simple experiment? For under £10-00, purchase a new, unused, 2Wire 2700HGV via eBay. Once it arrives, power it up but do not connect it to the xDSL line or a computer. Once it has stabilised (the relay has clicked, the power LED is solid green, the broadband LED is slowly flashing green), connect it to a computer via an Ethernet cable using a static address & route of 192.168.1.254 and then open a web-browser to the 192.168.1.65 IP address. That should bring up the modem/router's home page. Go to the set password page (http://home/xslt?PAGE=C_0_1) and change its password from the default. Now go to the broadband routing page (http://home/xslt?PAGE=C_1_3) and block the evil influence of BT's provisioning server by setting up null routes so that the 2700HGV is unable to "phone home". (Just add "66.193.112.0 255.255.254.0 192.168.1.100 bridge0" and "64.186.176.0 255.255.240.0 192.168.1.100 bridge0". That will result in all attempts to contact the provisioning server failing. :)  ) Now connect the 2700HGV to the xDSL line and allow it to sync with the FTTC DSLAM. This is an unknown step . . . I have not yet tried it and will not be able to do so until next Sunday (11th September 2011). If the 2700HGV and DSLAM do sync (at ADSL2+ Annex whatever speeds), there will be both SNRM and attenuation values available from the DSL Diagnostics page (http://home/xslt?PAGE=C_5_3). And that, if it is successful, should be better than a poke in the eye with a burnt stick. ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on September 05, 2011, 07:10:58 PM
Hi
quote:still no improvement to my download speeds.
If you mean the actual throughput then that is something else .
If your connection is now good and quiet without LOTS of errors then the download speed will be dependent  on your current SNR margin ,profile,any capping by your ISP )
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 06, 2011, 12:35:43 AM
Hi
quote:still no improvement to my download speeds.
If you mean the actual throughput then that is something else .
If your connection is now good and quiet without LOTS of errors then the download speed will be dependent  on your current SNR margin ,profile,any capping by your ISP )
Regards Jeff


@jeffbb,

Plusnet claim my connection is not capped on the dowstream, just the upstream is capped at 2 Mb.

From what I gathered from the last JDSU reading, everything looked reasonably O.K. downstream-wise, apart from my sync speed (& therefore download speeds). (SNRM was around 7 dB & attenuation was around 23 dB).

This leads me to believe the issue may well be faulty/stuck DSLAM/DLM equipment in the cabinet that may now require my D-side to be lifted & shifted to a different, previously unused DSLAM port that actually achieves 40 Mb at the cabinet, unlike the 22 Mb found when last tested by the BT engineer.

My IP Profile/bRAS rate is currently only 19410 k, allowing download speeds of only around 18 Mb or so.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 06, 2011, 12:44:22 AM
Hi All,

Not really much of a cause for a celebration (apart from the friendly advice and assistance received from you all), but yesterday was the 2 month anniversary of my speed issues first rearing their ugly head, & tommorrow will be the 1 month anniversary of my posting the first question in this thread:-

"1) Can anyone give me a realistic estimate of the stable profile / download speeds that I should be able to achieve with a copper line length of around 0.5 mile to the cabinet?"


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on September 06, 2011, 03:26:32 PM
Hi Bald_Eagle1,

Your support ticket has been updated.  I tried to call today but had to leave a voicemail.  I will try to call again tomorrow.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 06, 2011, 08:36:34 PM
Dear Readers,

Not very promising feedback from Plusnet's Alex Rolls today:-

Currently my line is operating at 20Mbps.
The profile set at the cabinet allows a speed up to 25Mbps currently.
This suggests that the line between my modem and the fibre cab is not capable of achieving a speed of 25Mbps with the current line configuration.

Whilst it's true that my line has seen higher speeds previously it may be that this is a burst speed and the line is not capable of transfering data at that rate long term.
Each time the line has been reset or an engineer has attended Plusnet are seeing the line eventually training back down to 20Mbps approximately.

As the line estimate is 14.6Mbps downstream then it may be that my maximum stable rate (MSR) is in the region of 20Mbps.
Bear in mind that nearly all ADSL lines could achieve a higher rate if Plusnet forced a faster line profile but left for a period of time the DLM would eventually return the line back to the MSR.

Alex will try to contact me again tomorrow to discuss this further as we didn't get the chance to speak over the phone today (not because it was crackling too much - it doesn't do that now anyway  ;D, but because I was in a meeting & had my mobile phone switched off)

More feedback tomorrow folks, but the inference from Alex's message isn't great is it?

I'm not sure that a couple of weeks of solid & stable download speeds of 30+ Mb, with no apparent random disconnections until the problems started could genuinely be seen as a burst speed though, could it?
I had certainly exceeded the 10 day DLM training period before the issues started.
The rest since then is well documented in this thread so I won't repeat it for all our sanity's sake.

Downstream attenuation 23dB, SNRM around 6dB, line length 820m = MSR of only 20Mb (half the maximum FTTC speed)? - Any fact based opinions anyone?

It would be nice, following the various BT caused issues, to be given a chance to try out a 40Mb at the cab connection & let DLM do its duty on my nice "fixed"  & now stable line though.

I wonder if anyone has physically checked the speed at the cab since it was last reported as 22 Mb?
If they have, I have not been informed of it. It could well still be at 22 Mb for all I know.

Now, if only I knew someone with a JDSU who just happened to be driving past PCP51 on Heywood Lane on their way home from work one day..................

EDIT:
Just as last thought, if I am currently achieving 20Mb from a 25Mb supposed cab speed, taking my latest stats into account, that equates to 80% of the cab speed.
If it does work pro-rata, 80 % of 40Mb at the cab would would equate to 32Mb. Haven't I mentioned that sort of speed earlier in this thread?



Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 06, 2011, 10:51:45 PM
Quote
I'm not sure that a couple of weeks of solid & stable download speeds of 30+ Mb, with no apparent random disconnections until the problems started could genuinely be seen as a burst speed though, could it?

There is no way that 2+ weeks of throughput (and not sync) downstream speeds of > 30 Mbps can be classified as a "burst".

I'm going to be quite blunt and speak my mind -- Either PlusNet are not telling the full story and have instructed OR, the owners and managers of the DSLAM within the FTTC associated with PCP51, not to set the DSLAM for 40 Mbps downstream sync or there is malfunctioning hardware within that FTTC which, currently, OR are unable to identify. (Or they have identified but, due to the cost involved, do not want to fix!)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on September 06, 2011, 11:38:29 PM
@ BKK,

I think you have that slightly wrong in that OR are not responsible for the DSLAM equipment which is probably owned by BT W. (There is proof positive around here if you look at a FTTC as the DSLAM compartment is fitted with star key locks whereas the IDC connector compartment has the standard triangle key locks.)

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: limbo on September 07, 2011, 01:41:54 AM
Hi everyone,

I've been watching this thread with interest, because I too have signed up to PN FTTC, since I would like something a bit faster than what we are currently getting (see this thread (http://forum.kitz.co.uk/index.php/topic,9901.0.html) for more info!).

It is due for installation on Monday, and I have been given an estimated download speed of 11Mbps with a 2Mbps upload.

What I find most interesting is this comment in an email from PN I got today, confirming the installation procedure.

Quote
When the engineer completes the work you may not experience fibre speeds straight away. This is because we need to manually adjust your speed profile when the order completes, so the change should be effective within 48 hours. Please be patient with us whilst we do this for you.

Now is this saying that they are going to set the speed profile at 11Mbps and leave it there, meaning that there isn't a training period for the line, or is it standard that they have to manually put it up to 40Mbps and let it drop to a stable sync rate? Sounds like I might be given the stock estimated speed for the line, which, if the line is capable of more, would be a disappointment (which we are all unfortunately too familiar with here)  ??? ...

Thanks,
Thomas
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 07, 2011, 08:07:40 AM
Hi everyone,

I've been watching this thread with interest, because I too have signed up to PN FTTC, since I would like something a bit faster than what we are currently getting (see this thread (http://forum.kitz.co.uk/index.php/topic,9901.0.html) for more info!).

It is due for installation on Monday, and I have been given an estimated download speed of 11Mbps with a 2Mbps upload.

What I find most interesting is this comment in an email from PN I got today, confirming the installation procedure.

Quote
When the engineer completes the work you may not experience fibre speeds straight away. This is because we need to manually adjust your speed profile when the order completes, so the change should be effective within 48 hours. Please be patient with us whilst we do this for you.

Now is this saying that they are going to set the speed profile at 11Mbps and leave it there, meaning that there isn't a training period for the line, or is it standard that they have to manually put it up to 40Mbps and let it drop to a stable sync rate? Sounds like I might be given the stock estimated speed for the line, which, if the line is capable of more, would be a disappointment (which we are all unfortunately too familiar with here)  ??? ...

Thanks,
Thomas


Hi Thomas & welcome to Kitz.

I am also quite new on here too & my posts have concentrated in this thread for now.
The guys in this forum are realy helpful & may be able to address matters from your other thread a lot better than I can.
I will say though your issues sounded rather similar to my situation for a while.

It does sound like you have a problem somewhere that may well completely cock up your FTTC speeds though.
Hopefully, you will receive sufficient sound advice in your other thread about how to deal with that side of things.

If memory serves me right, your download & upload speeds look like mine did when I was on a fixed 0.5 Mb profile when I first had ADSL broadband installed, although my distance from the exchange of around 5000m is quite a bit more than yours.
I eventually ended up syncing at around 1 Mb when I switched to ADSLMax (variable rate).

In my case, I had to switch to a different Plusnet product (Value) in order to be eligible for FTTC as I had to be moved from a 20CN connection to a 21CN connection (actually cheaper than what I had been paying for the last few years) in readiness for FTTC. I presume your are moving directly from BT to Plusnet's FTTC so that matter possibly isn't relevant?

The manual speed profile adjustment just means that when FTTC is first installed via Plusnet, you will probably still see your old download speeds for a while. I did & I was given a similar message to yours warning me in advance.
This may well stump the installing engineer as he should be seeing FTTC speeds at your master socket straight away.
My installation engineer was reluctant to leave as he couldn't see the 30+Mb on my PC's speedtests that he told me I would be able to achive for my connection's conditions. He thought it very strange that Plusnet had to adjust my profile manually.

All it means is that unlike BT & their Infinity product where FTTC speeds are seen immediately, Plusnet will have to manually adjust your profile to FTTC's 37Mb (Plusnet's name for the FTTC profile) after the engineer has confirmed the FTTC installation is completed.
In theory, this should be just a few hours after installation, but as it is a manual process, it may take a little longer due to staff workloads etc.
In my case, it took around 1 hour before I could see FTTC download speeds.
Apparently, Plusnet appear to occasionally overlook the profile reset & you may end up having to call them to give it a nudge.

My speed estimate was 14.6 Mb & I achieved over 30 Mb for a while. I am currntly achieving around 20 Mb following a number of line issues as detailed in this very long thread.

It now seems like Plusnet are about to give up trying to resolve this for me.

What I would strongly advise, & I wish I had done it at the time, is ask the engineer to give you as many connection statstics he can from his JDSU or other meter that he will test your connection with at your master socket.
Photograph the display if he will allow you to.
It may well come in very handy if you later have speed issues & at least you will be able to refer back to your connection's conditions at installation time. See the attached photo for the minimum details the engineer should give you. I took the photo during one of the BT engineer's "fault finding" visits, but I didn't have any details from installation date to compare them against.
If he won't let you photograph them, at least write them down & be insistent if he tries to avoid telling you.

It would be very helpful for us in this thread if you could post those stats here too as a comparison with mine & any others' FTTC stats as you will not be able to obtain them for yourself from the BT supplied modem. It is locked against users accessing their own connection stats  >:(
This obviously makes any trouble shooting almost impossible, then having to rely on BT engineer visits that could potentially cost you a lot of money if no fault is found at the time of his visit.

As you have mentioned in your other thread, a lot of the "basic" BT line tests result in LTOK.
A lot of tests carried out on my line have resulted in LTOK, but I have not had to pay for any of the now numerous visits so far as I also had a crackly phone line & complete loss of phone & broadband for 4 days etc. that had to be thoroughly investigated bt BT at no charge to me.

Final advice:-
Run regular speedtests (using the same speedtester for consistency). I use speedtest.net as it stores all your results over a long period of time, even when using the unregistered version.
Run regular BT performance tests as these are logged by BT & Plusnet are also informed. Really useful if/when trying to report a "fault".

Do you know which cabinet you will be connected to i.e. the line length from the cabinet to your home?
Once FTTC is installed, the line length all the way from the exchange can be ignored for broadband purposes.

Good luck, but be warned that as FTTC is fairly new technology, we don't fully understand exactly how it works yet, INCLUDING PLUSNET & SOME BT ENGINEERS & you may be given irrelevant "reasons" if your connection isn't performing properly.
e.g. both Plusnet & a visiting "special BT broadband engineer" have at some stage told me that I shouldn't expect high speeds from FTTC as my line is 5283m long. THAT IS ACTUALLY THE DISTANCE FROM THE EXCHANGE, NOT THE FTTC CABINET!!!!

Today's speed test result:-
(http://speedtest.net/result/1470253038.png)

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 07, 2011, 06:01:33 PM
Dear Readers,

Today's feedback:-

There is no feedback today as Plusnet's Alex didn't manage to contact me.
He must have been busy with other stuff.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: renluop on September 07, 2011, 06:28:19 PM
....He must have been busy with other stuff.

Paul.
Maybe reading up on Hari-Kiri?  :silly: ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 07, 2011, 08:41:15 PM
I think you have that slightly wrong in that OR are not responsible for the DSLAM equipment which is probably owned by BT W. (There is proof positive around here if you look at a FTTC as the DSLAM compartment is fitted with star key locks whereas the IDC connector compartment has the standard triangle key locks.)

Thank you, Walter. May we defer the question of who owns the cabinet DSLAM to the gentlemen employed by OR, Messrs RP & Ezzer?

I recall reading, somewhere, that special dispensation from Offcom was required so that the whole FTTC project could go ahead. It was something to do with the fact that the infrastructure provider, OR, would be providing an Internet connection when it is not a wholesale or retail service providing company. Basically the DSLAMs in an exchange are owned by a CP (BT Wholesale, TalkTalk, etc) but the DSLAMs in a FTTC environment (out in the street) are owned by the infrastructure provider (OR). Unfortunately, I can not put my paws onto an explicit reference / link. :(

One other thought has just come to mind. Mr Pag has gone on record as saying that he and his fellow CSEs are only allowed to access the tie pairs and copper side of a fibre connection and that there are other OR engineering staff who have been trained for fibre side working.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 07, 2011, 08:52:41 PM
There is no feedback today as Plusnet's Alex didn't manage to contact me.
He must have been busy with other stuff.

Perhaps in a meeting with Bob Pullen, discussing the best way forward in resolving your connection issue? ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 07, 2011, 10:56:45 PM
There is no feedback today as Plusnet's Alex didn't manage to contact me.
He must have been busy with other stuff.

Perhaps in a meeting with Bob Pullen, discussing the best way forward in resolving your connection issue? ;)

Haha. You might be right.

I bet they were discussing why it looks like I'm only getting ADSL speeds now.
It's almost as though someone/something has turned off or blocked my access to the higher VDSL2 frequencies & speeds.

If only I was able to see my own current modem stats & compare them against the stats when FTTC was first installed, we might have a bit of a clue where to start looking. Certainly none of the engineers who have visited have managed to find the missing Mb's.

I have asked Plusnet a few times to provide my original stats for comparison against the last engineer's JDSU readings.
If you recall, those were the stats for which the engineer told me he would be sacked if he let me actually look at the JDSU's display myself.
Surely Plusnet/BT must keep those sort of records.

All will be revealed tomorrow?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: limbo on September 07, 2011, 11:29:17 PM
Hi Paul, and thank you for the welcome!

Quote
In my case, I had to switch to a different Plusnet product (Value) in order to be eligible for FTTC as I had to be moved from a 20CN connection to a 21CN connection (actually cheaper than what I had been paying for the last few years) in readiness for FTTC. I presume your are moving directly from BT to Plusnet's FTTC so that matter possibly isn't relevant?

Walter very kindly looked my line up for me, and according to the OR database, and I am on a 21CN connection, so I think you're right, this shouldn't be a problem for me.

Quote
The manual speed profile adjustment just means that when FTTC is first installed via Plusnet, you will probably still see your old download speeds for a while. I did & I was given a similar message to yours warning me in advance.
This may well stump the installing engineer as he should be seeing FTTC speeds at your master socket straight away.
My installation engineer was reluctant to leave as he couldn't see the 30+Mb on my PC's speedtests that he told me I would be able to achive for my connection's conditions. He thought it very strange that Plusnet had to adjust my profile manually.

All it means is that unlike BT & their Infinity product where FTTC speeds are seen immediately, Plusnet will have to manually adjust your profile to FTTC's 37Mb (Plusnet's name for the FTTC profile) after the engineer has confirmed the FTTC installation is completed.
In theory, this should be just a few hours after installation, but as it is a manual process, it may take a little longer due to staff workloads etc.
In my case, it took around 1 hour before I could see FTTC download speeds.
Apparently, Plusnet appear to occasionally overlook the profile reset & you may end up having to call them to give it a nudge.

Thank you for explaining this- it makes a lot of sense now! And hopefully the OR engineer won't be scratching his head wondering why the connection speed is so slow!

Quote
What I would strongly advise, & I wish I had done it at the time, is ask the engineer to give you as many connection statstics he can from his JDSU or other meter that he will test your connection with at your master socket.
Photograph the display if he will allow you to.
It may well come in very handy if you later have speed issues & at least you will be able to refer back to your connection's conditions at installation time. See the attached photo for the minimum details the engineer should give you. I took the photo during one of the BT engineer's "fault finding" visits, but I didn't have any details from installation date to compare them against.
If he won't let you photograph them, at least write them down & be insistent if he tries to avoid telling you.

It would be very helpful for us in this thread if you could post those stats here too as a comparison with mine & any others' FTTC stats as you will not be able to obtain them for yourself from the BT supplied modem. It is locked against users accessing their own connection stats  >:(
This obviously makes any trouble shooting almost impossible, then having to rely on BT engineer visits that could potentially cost you a lot of money if no fault is found at the time of his visit.

I will take as much data as I can, and post it here. After reading the forum, I think I have a good idea how to get OR Engineers friendly; the biscuits will come out!!

Quote
Final advice:-
Run regular speedtests (using the same speedtester for consistency). I use speedtest.net as it stores all your results over a long period of time, even when using the unregistered version.
Run regular BT performance tests as these are logged by BT & Plusnet are also informed. Really useful if/when trying to report a "fault".

Do you know which cabinet you will be connected to i.e. the line length from the cabinet to your home?
Once FTTC is installed, the line length all the way from the exchange can be ignored for broadband purposes.

Good luck, but be warned that as FTTC is fairly new technology, we don't fully understand exactly how it works yet, INCLUDING PLUSNET & SOME BT ENGINEERS & you may be given irrelevant "reasons" if your connection isn't performing properly.
e.g. both Plusnet & a visiting "special BT broadband engineer" have at some stage told me that I shouldn't expect high speeds from FTTC as my line is 5283m long. THAT IS ACTUALLY THE DISTANCE FROM THE EXCHANGE, NOT THE FTTC CABINET!!!!

I read about them getting confused with the distances- that is a really fundamental error!

I have spotted a cabinet (I think it is FTTC- one of those new smaller ones (saw the thread on Fibre Cabinets!), with an older more tradition cabinet on the other side of the road. In fact when we drove past it earlier today there was an OR engineer in the old cabinet doing something!) which is 0.6 miles away (when we drove past it). I'm not sure if this is the right one, as there as a reasonable housing estate before it gets to us, and I would have thought that there might be one in there- I might go and have a walk around it! I've read that just because we see a cabinet doesn't mean it's the right one. There is also one about the same distance away in the other direction... However, I am led to believe that this is connected to the adjacent exchange, not the one I am on (rather ironically, it is much closer to us than the exchange we are connected to).

Thanks for all of your help & advice Paul- I'm sure it will come in very handy!

Thomas

Ps. I hope you have some good news tomorrow!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 08, 2011, 09:52:41 AM
Dear Readers.

This morning's results following a forced modem power reset:-
bRAS / IP Profile 20487k, showing a slight improvement on the recent 19410k.

(http://speedtest.net/result/1472031024.png)

Downloads at 07:25 this morning were approximately 96.7% of IP Profile.

According to the Kitz Max ADSL Speed Calculator, the above is roughly the equivalent of an ADSL2+ connection on a line length of 900m, Attenuation 13dB, Target SNR 6dB.

So, what could possibly be blocking my VDSL2 connection's additional higher frequencies (assuming that is actually the issue) & associated connection/speeds 24 hours per day that wasn't apparently blocking them when FTTC was first installed?

I would assume it isn't noise/interference being introduced along the route of my D-side cable or even in my home as the SNR values from the engineer's JDSU looked O.K. & I can't for the life of me think what other equipment could be running 24 hours per day that could be affecting my D-side, apart from the stuff in the cabinet itself.
Where I live, there are no industrial buildings & the area is not heavily populated with houses.

I am not aware that anyone has physically checked the DSLAM / port / Line Card inside the cabinet itself yet.
Could it simply be that they, and/or the DLM kit are faulty or "stuck" & my connection issues quickly & permanently cured by a lift & shift to a previously unused DSLAM port?
I believe a lift & shift is usually quite a standard procedure in resolving such matters. It was done on my previous ADSL connection via Plusnet a long time ago.

There appears to be some reluctance from Plusnet/BT to try a lift & shift, but I don't understand what the reluctance is, other than the regular reference back to my originally estimated 14.6Mb speed, even though nobody has been able to confirm how that estimate was arrived at.

The closest I ever got to an explanation, from Plusnet, was that it was based on line length & takes into account actual line attenuation & "other factors".
However, the Plusnet guy that told me that also quoted my reported 5283m line length, even though that is the length right back to the exchange.
I don't know how the attenuation & "other factors" on the D-side that is relevant for FTTC purposes would be calculated/estimated prior to FTTC installation.

Can anyone explain these estimated speed calculations for me?

More feedback later today folks, following Plusnet hopefully contacting me to discuss the current position/action plan.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: UncleUB on September 08, 2011, 10:10:07 AM
@ Bald_Eagle1......do you actually find the time to do anything on the internet other than monitor your connection and write your findings on here.......  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 08, 2011, 10:20:58 AM
@ Bald_Eagle1......do you actually find the time to do anything on the internet other than monitor your connection and write your findings on here.......  ;D

Hahaha.
It would appear not :lol:

I actually work from home a lot & dive in & out of the line issues stuff in between work matters.

Mrs. Eagle's not too chuffed about the amount of time I spend "messing about" with this when I should be finishing the house refurb though.

I wouldn't like Plusnet's Alex and/or now Adam to get on the wrong side of her. She can be quite "dangerous" ;)


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: limbo on September 08, 2011, 11:33:21 AM
Hi Paul,

One question, if I may:

How do you log modem disconnections? Presumably if you're on the internet then you would notice, but other than that, how do you know when it's happened (eg if it's been happening throughout the night)?

Thanks,

Thomas
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 08, 2011, 12:15:23 PM
Hi limbo,

I have the BT supplied modem & a Netgear WNR1000 router as supplied by Plusnet for an ethernet connection from the BT modem.

The modem as supplied by BT cannot be monitored as it is locked, but the Netgear router maintains an activity log, showing stuff like this:-

[Time synchronized with NTP server] Tuesday, Aug 30,2011 18:56:38
[Internet connected] IP address: 91.125.94.116, Tuesday, Aug 30,2011 18:57:00
[Internet disconnected] Tuesday, Aug 30,2011 18:48:53
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 16:55:57
[DHCP IP: (192.168.1.3)] to MAC address 00:01:E6:70:69:6C, Tuesday, Aug 30,2011 16:28:28
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.7], Tuesday, Aug 30,2011 16:08:19
[DHCP IP: (192.168.1.4)] to MAC address 00:1C:23:03:F9:4B, Tuesday, Aug 30,2011 12:46:44
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 12:27:07
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.10], Tuesday, Aug 30,2011 12:19:33
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.10], Tuesday, Aug 30,2011 12:08:01
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 11:03:43
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.6], Tuesday, Aug 30,2011 10:49:09
[Time synchronized with NTP server] Tuesday, Aug 30,2011 08:13:10
[Internet connected] IP address: 87.113.179.243, Tuesday, Aug 30,2011 08:13:58
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 08:12:34
[Internet disconnected] Tuesday, Aug 30,2011 08:07:29
[DHCP IP: (192.168.1.5)] to MAC address 00:24:2B:07:68:E6, Tuesday, Aug 30,2011 06:29:42

You can set the router to email the logs to you if you wish.
I have mine set to email me at 5:00am every day.
If you do choose that option, the router logs are cleared as soon as the email is sent, so you would have to save the emails for record purposes.

You will see from the above log that it can take quite a few minutes for the router to regain an internet connection, even though the BT modem only takes a few seconds (unless it is continually trying to re-sync due to line/connection problems etc.

If you haven't already received it yet, the Netgear router should arrive from Plusnet a day or so in advance of the FTTC installation & give you time to set it up with your own connection details/wireless access & security etc.

Plusnet can also confirm disconnections/reconnections via a chart, but usually only do so if they are trying to monitor your connection's stability etc.

If you choose to use a different router with the BT modem, it should also have its own logging facility.

HTH.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: limbo on September 08, 2011, 08:11:18 PM
Hi Paul,

Thanks for the explanation- that is very useful to know.

You're right about the router taking a long time to reconnect.

Out of sheer curiosity, if the router was unplugged from the modem, would that be considered losing sync from the DSLAM (and hence cause the IP profile to be lowered)?

Cheers,

Thomas
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 08, 2011, 09:09:35 PM
I can answer that for you, Thomas.

It is the modem (the OR provided HG612) that synchronises with the DSLAM in the fibre cabinet. So if the link between the modem and the router is broken, it is only your PPPoE session that drops. You would just loose your current authenticated session with your ISP / CP.

Hence "no" is the short answer. ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: limbo on September 08, 2011, 11:49:22 PM
I can answer that for you, Thomas.

It is the modem (the OR provided HG612) that synchronises with the DSLAM in the fibre cabinet. So if the link between the modem and the router is broken, it is only your PPPoE session that drops. You would just loose your current authenticated session with your ISP / CP.

Hence "no" is the short answer. ;)

Thank you for confirming this. I asked because I am going on holiday a week after the FTTC is installed, and we wanted to turn off as much as possible, but we don't want to have an inferior speed because we turned it off.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 09, 2011, 01:01:15 PM
Dear Readers,

There is a rather interesting thread going on over at thinkbroadband:-
http://forums.thinkbroadband.com/fibre/4040711-more-fttc-line-stats.html?vc=1

Well, interesting to me anyway ;D
I might have to try to get hold of one of them there unlocked modems as a spare, for research & information use only.

I would then be able to post some proper stats & graphs for your interest, delight, & hopefully sound advice as to what is actually wrong with my connection, & how to deal with it.

I am still awaiting Plusnet's feedback as to what happens next.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 09, 2011, 04:49:37 PM
Just a quick update folks:-

Another engineer's visit is being planned to further investigate this matter, hopefully for early next week.

I have asked Alex at Plusnet for clarification of what this will entail.

Until I receive that feedback I can only assume a "lift & shift" is now finally being considered as the further investigation refers back to previous fault ticket updates where it was mentioned as a possible option, along with returning my connection to the equivalent of a brand new FTTC installation..

I probably won't have much to report until the visit has been concluded.
How on earth will you all waste spend your time over what promises to be a sunny weekend without yet another essay from me to read? :lol: :lol:

I have the attached file on standby, just in case.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: tuftedduck on September 09, 2011, 05:26:03 PM
>>> How on earth will you all waste spend your time over what promises to be a sunny weekend without yet another essay from me to read? <<<  ;D

It's all being turned into a script for my new long running TV series...... :D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 09, 2011, 05:39:41 PM

It's all being turned into a script for my new long running TV series...... :D


Something like "The fall and rise of Reginald Eagle's download speeds"?

I didn't get where I am today by writing short forum posts.


Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: renluop on September 09, 2011, 06:25:28 PM
I didn't get where I am today by writing short forum posts.

And where's that then? ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on September 09, 2011, 08:22:28 PM
@ TD,

Perhaps we could invent the Geekers, an everyday story of nerdfolk.
Cue appropriate country dancing music complete with jingling bells, handkerchiefs and clouting sticks !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: limbo on September 13, 2011, 01:15:44 PM
Hi limbo,

I have the BT supplied modem & a Netgear WNR1000 router as supplied by Plusnet for an ethernet connection from the BT modem.

The modem as supplied by BT cannot be monitored as it is locked, but the Netgear router maintains an activity log, showing stuff like this:-

[Time synchronized with NTP server] Tuesday, Aug 30,2011 18:56:38
[Internet connected] IP address: 91.125.94.116, Tuesday, Aug 30,2011 18:57:00
[Internet disconnected] Tuesday, Aug 30,2011 18:48:53
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 16:55:57
[DHCP IP: (192.168.1.3)] to MAC address 00:01:E6:70:69:6C, Tuesday, Aug 30,2011 16:28:28
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.7], Tuesday, Aug 30,2011 16:08:19
[DHCP IP: (192.168.1.4)] to MAC address 00:1C:23:03:F9:4B, Tuesday, Aug 30,2011 12:46:44
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 12:27:07
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.10], Tuesday, Aug 30,2011 12:19:33
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.10], Tuesday, Aug 30,2011 12:08:01
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 11:03:43
[DoS attack: ACK Scan] attack packets in last 20 sec from ip [212.159.15.6], Tuesday, Aug 30,2011 10:49:09
[Time synchronized with NTP server] Tuesday, Aug 30,2011 08:13:10
[Internet connected] IP address: 87.113.179.243, Tuesday, Aug 30,2011 08:13:58
[Admin login] from source 192.168.1.100, Tuesday, Aug 30,2011 08:12:34
[Internet disconnected] Tuesday, Aug 30,2011 08:07:29
[DHCP IP: (192.168.1.5)] to MAC address 00:24:2B:07:68:E6, Tuesday, Aug 30,2011 06:29:42

You can set the router to email the logs to you if you wish.
I have mine set to email me at 5:00am every day.
If you do choose that option, the router logs are cleared as soon as the email is sent, so you would have to save the emails for record purposes.

You will see from the above log that it can take quite a few minutes for the router to regain an internet connection, even though the BT modem only takes a few seconds (unless it is continually trying to re-sync due to line/connection problems etc.

If you haven't already received it yet, the Netgear router should arrive from Plusnet a day or so in advance of the FTTC installation & give you time to set it up with your own connection details/wireless access & security etc.

Plusnet can also confirm disconnections/reconnections via a chart, but usually only do so if they are trying to monitor your connection's stability etc.

If you choose to use a different router with the BT modem, it should also have its own logging facility.

HTH.

Paul.

Hey Paul I'm looking through my router's logs (btw, I can't seem to get the email bit of it to work; do you use your PN email account? Both Gmail and Live don't want to work).

It seems that my router takes less time to reconnect than yours:

[Internet connected] IP address: 80.229.127.146, Tuesday, Sep 13,2011 02:26:59
[Internet disconnected] Tuesday, Sep 13,2011 02:26:41
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 13, 2011, 01:25:40 PM
Hi Thomas,

Yes, I do use my PN account for the router email logs.

I'm not at home at the moment to check the settings I used, but let me know if you want me to confirm them later on.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on September 13, 2011, 03:46:36 PM
@Bald_Eagle1

Your support ticket has been updated.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 13, 2011, 05:59:32 PM
@Bald_Eagle1

Your suppor ticket has been updated.

Cheers Alex,

Are you able to confirm what the engineer will actually be doing tomorrow (we have previously discussed lifting & shifting/port swapping and other options etc. in order to return my connection to the equivalent of a fresh installation) & how long he/she will be able to spend dealing with this?
I did ask you via the Plusnet support ticket, but you may have missed my query.

I notice from Plusnet's newsgroups that your providers (I assume BT???) have been updating your software in the early hours of this morning.
Is this likely to have any bearing on matters?:-

"What does it affect?
The routing of customers' broadband traffic.

How long will it take?
About five hours.

What does the work involve?
Our suppliers are performing a software upgrade.

Am I likely to notice the work?
Some customers on 21CN connections will experience a loss of connection
for at least 20 minutes between1.30am-3.00am. Brief disconnections are
also possible at any time during the maintenance window."

My router logs reported a disconnection at around 11:30 last night, but no disconnections during today.
Was that possibly due to the software upgrade being started earlier than planned?

Finally, I hope you have already mentioned to BT that I must be allowed to see & record any statistics as displayed on the engineer's JDSU or similar device.

I will be very disappointed, to put it very mildly, if the engineer refuses to disclose the connection stats again.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on September 14, 2011, 01:05:59 PM
 :drink:  nearly 21  :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 14, 2011, 01:43:12 PM
Good afternoon Readers,

Feedback from today's engineer's visit:-

The OR Engineer arrived with no brief other than to find out what the issues have been & to fix them as necessary.

After a very brief summary of the issues, he accepted that I had indeed achieved download speeds in excess of 30Mb, which made a refreshing change. (see lower down for the engineer's theory on this)

He allowed me to photograph his JDSU, but unfortunately my camera skills are very poor, as you will see in the attached photo.

What I did glean though, was my US Line attenuation had gone down from 52.9dB to 21.9dB & my DS Line attenuation had gone down from 30.2dB to 23.0dB since the previous photograph of the JDSU.

He showed me the VDSL summary screen (thanks Thomas for obtaining that screen during your recent installation), which showed an estimated length of 1.1km.

I explained about the 22Mb or so that was seen recently at the cabinet, so off he went to check.

After quite a while, he returned with the following comments:-

I would not be allowed to photograph his JDSU again, but I was allowed to see it (he must have spoken to someone back at BT, as he had no qualms at all when I took the photo on his arrival).
I didn't manage to jot all the figures down, but it showed DS Actual Rate of 23500k & DS Max Rate of 23514k.
The estimated length was now showing as 1.0km

He had checked my connection at the cabinet, & as it was immediately showing lots of "errors", he had performed a lift & shift to a new DSLAM port.
This action sorted out the errors, & the speed following the L & S was actually 40Mb at the cabinet.

When I queried the still low speeds at home, he mentioned that the previous engineer had shown me "something" from BT's Network Records, but that it was the wrong screen as it didn't show the actual line route.
Therefore the previous engineer's reported line length of only 820m was incorrect & that it probably is actually around 1.0km as shown today on the JDSU.

The engineer's theory is that my new download speeds, currently around 22Mb are probably about right for the distance from the cabinet, unless something is still capping them. They are indeed slightly better since today's Lift & Shift.

He went on to state that via fibre, the cabinets currently receive "up to" 80Mb & that BT currently cap download speeds at a maximum of 40Mb for all customers.
Those living close to the cabinet (say up to 500m or so will indeed be able to download at around 38Mb or slightly higher, with those living further away achieving less, based upon signal loss over the copper D-side.

There are apparently tentative plans to provide "uncapped" connections in the not too distant future, no doubt at additional cost?.

He also added that typically, FTTC speeds are completely uncapped during the 10 day training period & that he has actually seen actual download speeds in excess of 60Mb at the end user's home.
In theory, the 40Mb cap is introduced immediately following the 10 day training period, but "occasionally" it gets missed & the user continues to enjoy higher than 40Mb download speeds.

He thought that it was possible that I was obtaining 33Mb or so for the first couple of weeks, because my connection was "open" to whatever uncapped speeds could be delivered, & as soon as the 40Mb cap was introduced, my line length would only allow up to 25Mb or so.

I have previously queried more than once whether speeds are uncapped during the training period & the answer has been that they are not.

He also thought that my various previous issues such as a crackly phone line, frequent random disconnections, HR fault (double jumpering), total loss of servce for a number of days etc. may well have been pure coincidence & a bit of a "red herring" in matters.

These theories could have some validity, but I will be asking Plusnet to confirm on my behalf that neither they, or BT are currently capping my download speeds for any reason.

So, that may be that now. I may finally have to accept download speeds of around 22Mb as shown here, obtained since the engineer finished his job today:-
(http://speedtest.net/result/1482169340.png)

There still appear to be many uncertainties around BT's current FTTC provision, with various "experts" providing conflicting advice (as previously demonstrated in this very thread).
THIS NEEDS TO BE QUICKLY SORTED OUT ONCE & FOR ALL, SO THAT END USERS CAN ACTUALLY UNDERSTAND MATTERS ACCORDINGLY, IN THE SAME WAY THAT ADSL TECHNOLOGY (& ACHIEVABLE DOWNLOAD SPEEDS) ARE UNDERSTOOD.

How difficult should it really be for BT & ISPs to publicise a "typical" & realistic speed graph/chart based upon distance from the cabinet at a starting speed of 40Mb?
Surely, between them, they MUST have sufficient data based upon actual installations by now.

Furthermore, how difficult should it really be to provide customer help desk staff (& BT Engineers) with simple & accurate fact sheets, actually based upon facts?


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 14, 2011, 01:45:27 PM
:drink:  nearly 21  :lol:

Hi Jeffbb,

I tried to make my latest posting long enough to get us to the celebratory "21 today" stage, but failed.

Paul.

EDIT: I now see that Just another line or two would have done it  :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on September 14, 2011, 02:48:07 PM
@Bald_Eagle1

Your support ticket has been updated.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 14, 2011, 05:46:44 PM
Thanks Alex,

I have responded as just a couple of final queries remain, particularly (but not only) regarding the engineer's theory regarding BT's FTTC provision being completely uncapped during the 10 day training period, hence a "possible" explanation for my initial higher download speeds.

It doesn't explain why another Plusnet user, named limbo in this forum, only achieved 26Mb (compared to my initial 33Mb) following his FTTC installation this Monday, although he apparently has a shorter D-side than I have.
see http://forum.kitz.co.uk/index.php/topic,9901.msg200191.html#msg200191


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 02, 2011, 06:49:28 PM
Dear All,

I haven't posted for a while for 2 reasons:-
1) I have been busy with other things
2) As suggested by Plusnet, I have waited to see if my connection would fix itself given time!!!!!

Well, these are this morning's results
(http://speedtest.net/result/1512200325.png)

Not only is the download speed down yet again, the upload speed is now only 0.67Mb from a 2Mb capped service.
It is usually around 1.6-1.7Mb.

I have also suffered a few disconnections recently (possibly coincidental with the unseasonal heat-wave?)

My stats are attached below.

DS Band D2 is the one used for VDSL2 fequencies.
You will see that I am receiving hardly anything in this band, probably due to the high attenuation level.

I do have graphs from earlier this morning showing absolutely nothing at all for DS Band D2, but at least my US speed was still O.K.

I have also attached someone else's stats from a good connection as a comparison.

Plusnet closed my previous (UNRESOLVED) ticket, so it seems like I'm back to square one again.

Don't panic though. I won't be making any more epic posts.

Paul.

P.S. I must say a big thank you to asbokid from the TBB forum (& an occasional visitor here) for making access to our stats possible, & also a big thank you to b*cat for his patience & assisting me with his Linux knowledge to convert the Linux graphing script into a Windows Batch file (even though he claims to know nothing about Windows  ;) ).
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 02, 2011, 09:40:19 PM
Having downloaded both graph sets, I then displayed them as a continuous slide show and the high frequency degradation was abundantly clear.

If Mr Pag (Razpag) was still "one of us", I would ask for his opinion on my diagnosis of a possible HR joint. Clearly there is something amiss with the copper pair between the NTE5/A (in the Aerie) and the DSLAM (in the fibre cabinet, situated on Heywood Lane). :(

Another OR engineering visit will have to be arranged by PlusNet, methinks. :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 02, 2011, 11:00:18 PM
Hi Paul & BKK,

It also seems clear that an enhanced escalation procedure is required which might well require technical input from BT Wholesale specialists.
Given the limited DSLAM technical training BT openreach seem to be given, it seems quite unreasonable that a BT O engineer is expected to be able to solve this type of intermittent fault.
At a practical level, how can a BT O engineer interpret the diagnostic data presented to him ?

Without additional help this sort of problem could go on for many months (if not to Infinity) and at significant expense and inconvenience to all concerned.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on October 03, 2011, 08:25:03 AM
Well, not to make to light of this fault it seems to fall into the kind of fault finding I did for the last twenty years of my working life. No i am not qualified nor extensively knowledgeable of the Telecom industry.
Having said that I have read through this post and deciphered that there is no apparent fault on the copper wire from Paul's house to the terminal cabinet for the copper run. There appears to be no fault from the exchange to terminal cabinet for the fibre. If I understand this correctly there must be a point where the copper joins the fibre. Using my experience as a fault finding engineer and an experience I had with a particular electrical fault, I would think (suggest) the problem lies in the area where the two meet up.

The scenario I was faced with was a dead photocopier. There was correct electrical readings throughout the machine, no blown fuses etc. There was 240 volts coming from the wall socket, the plug was wired correctly. The answer was obvious that the socket was faulty in some way. I had to insist that some-one from the company do a visual check on the socket wiring. Lo & Behold it was found the Neutral wire was not secured into the back of the socket.

I trust one can see the resemblance to Paul's fault, all the connection readings are correct, yet there is this HR fault. Has any of the engineers done a physical check on where these two cables join. If it's not a physical join, but a piece of equipment that does the joining then if it has not already been replaced then I would place some money on this piece of equipment.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 03, 2011, 09:24:36 AM
Hi SS & Paul,

If my memory has not disappeared entirely, I recall that BT O did a "Lift & Shift" in the FTTC. If so, perhaps with PN's confirmation that a new port is now in use, that should have eliminated anything within the link cables and the FTTC.

Assuming that BT Wholesale will be reluctant to intervene, one of the few remaining options for BT O are to investigate the D side line to Paul's house.
Drop wire 12 should be used to replace the entire house-end wiring together with a new NTE as well. That must be followed with an new pair connected back to the PCP.

Perhaps if PN are also fed up with the time this fault is consuming, they might escalate the matter via their BT W contacts to ensure the problem is tackled completely ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 03, 2011, 10:11:10 AM
Hi SS & Paul,

If my memory has not disappeared entirely, I recall that BT O did a "Lift & Shift" in the FTTC. If so, perhaps with PN's confirmation that a new port is now in use, that should have eliminated anything within the link cables and the FTTC.

Assuming that BT Wholesale will be reluctant to intervene, one of the few remaining options for BT O are to investigate the D side line to Paul's house.
Drop wire 12 should be used to replace the entire house-end wiring together with a new NTE as well. That must be followed with an new pair connected back to the PCP.

Perhaps if PN are also fed up with the time this fault is consuming, they might escalate the matter via their BT W contacts to ensure the problem is tackled completely ?

Kind regards,
Walter

Hi Walter,

Yes, the lift & shift was supposedly done 14th September.
Speeds did marginally improve for a day or so, but only to about 22Mb (still 10-11Mb short of the initial speeds).
So it didn't appear that I was being provided with a "brand new" installation as promised.

The SFI engineer even phoned Plusnet to query why on earth I was looking for more than 20Mb because I was already achieving it at the time.
Plusnet had to explain to him that FTTC is an "up to 40Mb" service, not ADSL2+ speed.

I have still not received any confirmation that at least 40Mb is available at or near the cabinet, or that my BT profile had been reset to 40Mb for the training period to start all over again.

I saw the modem resyncing when the engineer did the L & S, or whatever it was that he did.
Within seconds, I had conducted a speed test that showed nowhere near 30Mb, never mind 40Mb.
Within minutes of the engineer leaving I had reconnected the unlocked modem & was only achieving an Attainable Rate of 25124 K & a Line Rate of 25067K.

If you also recall, the "double jumpering" was supposedly tracked down by the use of TDR testing, but NOT retested after the double jumper was removed as "it wouldn't be necessary as the fault has been fixed".
Maybe the double jumper was contributing to the issues, but not the major factor?
Whenever I "fix" anything, I test afterward to make sure there isn't still some other underlying fault.

I have asked Plusnet's Bob Pullen to do whatever he can to escalate this issue accordingly for a quick & satisfactory resolution once & for all.

What is Drop wire 12? I haven't heard that term before.


Paul.

EDIT:
Found it:-
http://www.caledonian-cables.co.uk/Telephone/Indoor/CW1406.htm
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 03, 2011, 10:36:52 AM
Hi Paul,

I suggested drop wire 12 as a replacement as it has larger 0.9 mm dia wires and as a single pair there is no possibility of a second pair affecting it.

Remember that the up to 40 Mbps is the modem sync rate. On one good FTTC service in Guildford, at about 100 m from the FTTC, that line achieves an average throughput of 37.1 Mbps which perhaps should be recorded as the maximum practical throughput speed.

Although there is more variation in throughput speeds, my Virgin Media service usually achieves around 95 Mbps which is undoubtedly the better solution where VM have installed their services. Sadly that is not everywhere !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on October 03, 2011, 11:00:24 AM
Wouldn't it be a tad expensive to replace all the cabling?
Also quite disruptive?

If the cabling from the pole to cabinet runs via ducting then I could see a replacement as a solution. If the cable is via some other means well!!!

PS I could look up the acronyms but for what I will be posting? ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: asbokid on October 03, 2011, 11:11:42 AM
Hi Paul..

I think Walter has nailed it.... 

My layman's understanding of your line stats graphs is that they suggest that something is physically wrong with your loop.

I just made a blog post about the four metrics in the graphs (BITS, SNR, QLN, and HLOG).[1]

Perhaps most interesting in your case is your chart of Hlog(f). I believe it illustrates the problem.

Hlog(f) is a logarithmic measure of the channel insertion loss.  In other words, it measures loop attenuation at individual sub-carrier frequencies across the band-plan spectrum.

The plot of Hlog(f) needs to be read upside-down. It is actually inverted, insofar as the lowest point of the red zone charts the attenuation reading for a given frequency. (An attenuation measurement of -96dB means the data is not available or is out of range).

We can identify the following characteristics of the attenuation on your loop from Hlog(f).

The lowest utilised sub-carrier in the lower D1 downstream band is DMT ~#36 which is transmitted at ~150kHz.  (Remember vDSL Profile 8c uses 4.3125kHz channel spacing, so 36 * 4.3125 = 150kHz.)

In your 'good' Hlog graph, a channel insertion loss of -6dB was measured at 150kHz.  In the 'bad' Hlog graph, a channel insertion loss of -12dB was measured at the same frequency.

The highest utilised sub-carrier in the lower D1 downstream band is ~#690. This tone is transmitted at ~3.0MHz. In the 'good' graph, a channel insertion loss of -17dB was measured at that frequency.  However, in the 'bad' graph, attenuation at 3.0MHz has jumped to -45dB.

In the second downstream band (D2), the lowest tone is ~#1195. This tone is transmitted at ~4.9MHz. The loop attenuation measured at the frequency in the 'good' graph was ~-25dB. However, in the bad graph, the measurement was ~-65dB.

The highest utilised tone in D2 is DMT #1625. It is transmitted at ~7.0MHz. The 'good' graph shows loop attenuation of ~-27dB at that frequency, whereas the 'bad' graph shows a loss of ~ -75dB.

So in the period of time between the data collection for those two graphs, your loop mysteriously developed a high attenuation profile across the whole bandplan spectrum.

The attenuation measurements by themselves are not that useful. The sensitivity of the ADSL transceiver units will actually determine whether the signal at a given frequency can be recovered.

What's more important for diagnostic purposes is the slope of the Hlog graph which takes the form of an exponential decay function.  Characterising the Hlog graph is not straightforward. Since the ordinate scale shows negative decibels you could call it an exponential growth function as attenuation grows as the frequency gets higher.

It would be useful to use non-linear regression (curve fitting) to discover the parameters of the attenuation function for a given loop.  That's what I am trying to develop as part of the port of the dmt tool for use with vDSL connections. I see that Huawei Corp has patented a couple of ideas in that sphere. If anyone would like to collaborate on an open source project to do this, please contact.

Once the parameters of the attenuation function are identified, it could be superimposed upon the 'classic' attenuation functions for the typical loop, enabling diagnosis by comparison.

For example, the parameters of the attenuation function for a (faultless) single segment twisted pair constructed to BT cable specification CW1128 - class 1 solid annealed 0.5mm plain copper conductors with cellular polyethylene (CEL-PE) insulator - will be well known to the egg-heads at Martlesham Heath. 

They will also know the (higher) attenuation profile of the aluminum twisted pairs that were used as a substitute when copper prices soared at the hands of the City gangstas in the 1970s.

Here are some plots of the attenuation functions for twisted pairs using various wire gauges (AWG24 has 0.5mm conductors). The plots were taken from [2] and [3] and are only meant for illustrative purposes. The units of measure and the graph scales are all over the place. To develop anything out of it, we need the parameters of the functions to plot those graphs. Then they could be used for various comparisons.

(http://huaweihg612hacking.files.wordpress.com/2011/10/attenuationfunctions.jpg)

According to a European patent filed by Huawei in Sweden, the attenuation profile of a loop can be used to accurately estimate its length and to gauge its physical condition.

Enough rambling!

Cheers,
A

[1] http://huaweihg612hacking.wordpress.com/2011/10/01/measuring-line-characteristics-on-the-huawei/
[2] http://www.cc.gatech.edu/classes/AY2005/cs4251_fall/class5.ppt
[3] http://www.serialphy.com/attenuation-chart-24-awg-wire.html
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 03, 2011, 11:44:49 AM
Hi Paul..

I think Walter has nailed it.... 

My layman's understanding of your line stats graphs is that they suggest that something is physically wrong with your loop.

I just made a blog post about the four metrics in the graphs (BITS, SNR, QLN, and HLOG).[1]

Perhaps most interesting in your case is your chart of Hlog(f). I believe it illustrates the problem.

Thanks asbokid for your clear explanation & links to sources of information.

I could see what appeared to be wrong with my connection, but just couldn't put it into plain words.

Now, as my connection has delivered much higher & stable speeds of 30Mb+ throughput in the past, it appears that I simply need to get BT (via my ISP & phone provider Plusnet) to find the fault(s), somewhere physically in my connection & fix it/them once & for all.

That sounds very simplistic, but in reality....................?
I am but one small voice in a mighty organisation's service provision.

The intermittent nature of this issue (e.g. the dramatic downturn over the last few days of unseasonably hot weather) is understandably causing some diagnosis difficulties & appears to have an incredibly detrimental effect upon how DLM automatically restricts my speeds (assuming at least 40Mb is really being delivered to the cabinet where the DSLAM & DLM equipment is installed.

BTW, all the modems have stayed quite cool to the touch throughout these issues, so there would appear to be no point in replacing them just as a matter of course.

I have pointed various Plusnet staff members to this thread & requested the matter be escalated accordingly, so hopefully the additional explanation/information you have now provided will go some way in helping to speed matters along.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 03, 2011, 12:01:00 PM
Wouldn't it be a tad expensive to replace all the cabling?
Also quite disruptive?

If the cabling from the pole to cabinet runs via ducting then I could see a replacement as a solution. If the cable is via some other means well!!!

PS I could look up the acronyms but for what I will be posting? ::)

Hi Silversurfer44,

The cable from the nearest pole to my home is overhead, as is much of the cable from the cabinet.

One of the engineers did mention that it is steel reinfoced though.
I wasn't sure if he meant just the main runs, or from the pole to home, or both.
The cable from the pole to home doesn't look very thick though.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on October 03, 2011, 12:38:03 PM
If you look at the cable from your home to the pole looks black then it will be the reinforced variety, if it looks grey and similar to a twin flex for a lamp then it is not the reinforced.
The two are very distinctive, I have both running to my house and can see the difference.

I have just been looking back through your novel and noticed the question of aluminium was never resolved, I think it finished on a maybe. Regardless of that I do believe the answer is in pure simplicity of good and bad connection/wiring. It would appear as the stare in the face type fault is being overlooked.

I applaud asbokid in his knowledge and depth of explanation, however it reminds me of the tale of the mathematician and the jar of pickles. The mathematician could tell you the perimeter of the lid, the inside area, the thickness absolutely every dimension you could think of, but he couldn't tell you how to get the lid off to get to the pickles.
I am not casting aspersions or anything asbokid, just that throughout this riveting novel the same thing has been done, and, I think the powers that be are still doing it.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 03, 2011, 01:06:39 PM
HI Paul,

Just to add a little to SS's comments, a black drop wire contains steel catenary wires as well as the copper twisted pair(s) you'll see from the cable spec you found whereas BT's multicore distribution cables have a separate steel wire incased in a much smaller diameter PVC envelope. The picture in this link shows a BT pole demolished by a buffoon behind the wheel ! You can see where the catenary wire has been pulled out of one 50 pr cable and another through-cable where BT obviously ran out of serviceable pairs. The die-cast pole support has been forced through nearly 90 degrees as the cables are supporting the pole instead of vice versa. The line clamps only bite into the catenary cable and not the larger twisted pair one.

I am hoping that BT O might replace your drop wire as it is relatively inexpensive. If they do perhaps you could ask the engineer to leave the catenary wires just outside the NTE so you could experiment by earthing them to see if that has any screening effect.

http://www.scribd.com/doc/67277255

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 03, 2011, 01:09:19 PM
If you look at the cable from your home to the pole looks black then it will be the reinforced variety, if it looks grey and similar to a twin flex for a lamp then it is not the reinforced.
The two are very distinctive, I have both running to my house and can see the difference.

I have just been looking back through your novel and noticed the question of aluminium was never resolved, I think it finished on a maybe. Regardless of that I do believe the answer is in pure simplicity of good and bad connection/wiring. It would appear as the stare in the face type fault is being overlooked.

I applaud asbokid in his knowledge and depth of explanation, however it reminds me of the tale of the mathematician and the jar of pickles. The mathematician could tell you the perimeter of the lid, the inside area, the thickness absolutely every dimension you could think of, but he couldn't tell you how to get the lid off to get to the pickles.
I am not casting aspersions or anything asbokid, just that throughout this riveting novel the same thing has been done, and, I think the powers that be are still doing it.

Hi SS44,

The cable from the pole is black.

Regardless of aluminium or not, I had a high(ish) speed & stable connection for a while.
Now I don't (& haven't for quite some time now).

Please Mr. BT Man, fix it - "Simples".

Asbokid has managed to get the lid off the modem, & we are at last able to see our pickles / connection statistics.
Prior to that point, everything was just assumptions & guesswork.

It is all asbokid's fault for not unlocking the modems in time for me to have gathered my stats immediately following FTTC's installation  :lol:.
I would at least have been able to compare my current stats against the "good" stats that BT and/or Plusnet do not possess (or so they tell me).
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: asbokid on October 03, 2011, 02:05:25 PM
The cable from the pole is black.

Regardless of aluminium or not, I had a high(ish) speed & stable connection for a while. Now I don't (& haven't for quite some time now).

Please Mr. BT Man, fix it - "Simples".

Asbokid has managed to get the lid off the modem, & we are at last able to see our pickles / connection statistics.
Prior to that point, everything was just assumptions & guesswork.

It is all asbokid's fault for not unlocking the modems in time for me to have gathered my stats immediately following FTTC's installation  :lol:.
I would at least have been able to compare my current stats against the "good" stats that BT and/or Plusnet do not possess (or so they tell me).

I was looking again at your graphs. The plot of Quiet Line Noise shows an average of ~20dB more noise between the 'good' and the 'bad' graphs.  The data readings for QLN are taken during the xDSL initialisation and training phase and before the xDSL connection is active. The readings may also be re-taken at any point thereafter at the request of either the CPE modem (known as the ATU-R) or the DSLAM (the ATU-C).

The steep narrow 'spike' in the noise measurement around tone #250 (1MHz) is very distinctive.

Burakkucat already alluded to the likelihood of a high resistance joint or splice being the physical cause of your line problem.  If that's what it is,  then perhaps it's aggravated by environmental conditions - humidity/water ingress, elevated ambient temperature etc..

Below are some Application Notes by Chris Dunford from EXFO, an expert in telecoms test and measurement systems.  His Notes contain a number of oscilloscope traces from Time Domain Reflectometry tests on faulty lines. The traces show the effects of each type of fault.[1]  Of course, all we can do with the Huawei is analyse the magnitude responses in the frequency domain.  How they can be correlated with the TDR results (if at all), I don't know  ???

The document linked at [2] is the Masters Thesis of Matthias Ernell, a postgraduate at KTH, the Royal Institute of Technology in Stockholm. The title of Ernelli's work is "Loop Qualification for VDSL2". At the time he authored the document (2008), Ernelli was working for the Swedish telco, Telenor and must have gained a lot of wisdom and inside knowledge from that employment.  The thesis is really well written, and perhaps the best technical document I've ever read on xDSL.  Chapter 3 is dedicated to Loop Measurement, the characterisations that our graphs try to reproduce.

Cheers,
A

EDIT Link to Application Notes containing TDR scope plots; Corrections to comments about the 'spike' around 1MHz in Paul's QLN graph; Reference to Ernelli's work

[1] http://documents.exfo.com/appnotes/anote168-ang.pdf
[2] https://eeweb01.ee.kth.se/upload/publications/reports/2008/XR-EE-KT_2008_003.pdf
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 04, 2011, 07:39:05 AM

So in the period of time between the data collection for those two graphs, your loop mysteriously developed a high attenuation profile across the whole bandplan spectrum.


@ asbokid,

Just to clarify the origin of the graphs, the "bad" one is mine from 2nd October & the "good" one is from another user who is achieving the full 40Mb DS & 10Mb US.

My US is capped at 2Mb with my Plusnet package.

I don't have modem statistics from when I was achieving over 30Mb DS throughput, but to have achieved that level of throughput, my line's statistics & therefore quality MUST have been much better than they are currently.

The only other explanation would appear to be that maybe BT had not implemented their 40Mb DS cap during, & a little beyond the 10 day training period.
If that was the case, my throughput speeds would have been attenuated down from over 50Mb to the typically 32-33Mb that I achieved.

The latest visiting engineer had that theory, but he did admit that it was only his personal theory, unconfirmed by BT.

However, as Plusnet have confirmed that their speed cap is 40Mb from the outset & also confirmed that BT's cap is 40Mb from the outset, the current statistics would appear to confirm some sort of resistance/loss of signal (or speed capping) in my connection that wasn't previously present.

I have attached graphs from immediately following a recent lift & shift operation, when I achieved around 21-22Mb throughput for a short while.
It is thought, but still unconfirmed, that 40Mb was available for my connection at the cabinet following the L & S.

So, the remaining question is what can BT now do to locate the line "fault" & to reinstate the quality of my connection to its original standard.

Finally, as the reported SNRM level was high earlier this morning, I forced a modem reboot.
However, the DS rate for Path 0 is now only 14999K, but the US rate has gone back to 2000K.
This is from an Attainable Net Data Rate of 24012K DS & 6966K US.
This now gives this throughput & suggests BT's DLM capping of their basic 15Mb:-

(http://www.speedtest.net/result/1515710212.png)

Confirmations from BT's online checker & another online checker that accesses BT's systems are that my current BRAS rate (IP Profile) is: 12674 k


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 04, 2011, 09:04:38 AM
@ Paul,

I don't understand how you can remain so calm !

Just to remind everyone the "up to 40 Mbps" is the synchronisation speed whereas the speed test is one of actual throughput. I know of one good service around here at about 100 m from the FTTC where the throughput is around 37 Mbps.

I've also noted that bRAS figures usually recover within about 24 hours instead of in days, so perhaps some observations this evening and tomorrow might see some further speed restoration.

The pressing question is how do we get BT Openreach to listen to the ISP and rectify the anomaly once and for all ?

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 04, 2011, 09:53:01 AM
@ Paul,

I don't understand how you can remain so calm !

Just to remind everyone the "up to 40 Mbps" is the synchronisation speed whereas the speed test is one of actual throughput. I know of one good service around here at about 100 m from the FTTC where the throughput is around 37 Mbps.

I've also noted that bRAS figures usually recover within about 24 hours instead of in days, so perhaps some observations this evening and tomorrow might see some further speed restoration.

The pressing question is how do we get BT Openreach to listen to the ISP and rectify the anomaly once and for all ?

Kind regards,
Walter

Cheers Walter,

I also need to get the ISP to listen to this end user, rather than have them keep requoting my original (& widely acknowledged as ridiculously conservative) BT speed estimate of 14.6Mb.

The fact remains that I achieved stable high speeds for a reasonably prolonged period, completely regardless of the pre-install estimates.

If I could achieve them previously, something must now need "fixing" that has deteriorated between then & now.

If my line had always been sub-standard, surely I could never have achieved the higher speeds.

You have already seen estimates for yourself, relating to a property just across the road from me, of 27.9Mb, along with a statement that users in the area have achieved those speeds.
They must have been my achieved speeds, as there are not many other properties in my area & I was indeed stuck at 27.9Mb for a while following the first batch of disconnections that were initially suspected to be due to an overheating modem.

EDIT:
I have been told by a number of Plusnet staff that via FTTC, reductions in bRAS/IP Profile can be more or less instant, & that recovery can take up to 10-14 days.
Hence my absence from this forum for a while.

Current modem screenshot attached.
I note no errors.
I usually have quite a few when synched at a higher speed.


Paul.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on October 04, 2011, 03:55:21 PM
Hi
Is the line attenuation of 0 db a reporting error ?
Regards jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 04, 2011, 06:59:43 PM
Hi Jeff,

If I can deputise for Paul, I believe asbokid has discovered a generic bug in all modems using the chip in this one; it produces a 0 attenuation on VDSL services but not ADSL ones.

All part of life's rich tapestry !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: asbokid on October 04, 2011, 07:11:58 PM
Hi
Is the line attenuation of 0 db a reporting error ?
Regards jeff

Hi Jeff,

It's a firmware bug that is present in other devices that are based on the Broadcom 6368 VDSL2 chipset.

It is present because Broadcom hasn't updated the API between the webserver and the xDSL driver MIB for this particular chipset.

The webserver still looks to the MIB variables that were used to hold the ADSL2 attenuation measurements.

However, VDSL2 uses multiple upstream and downstream channels, (U0,U1,U2 and U3) and (D1, D2 and D3).

Somebody decided that a single (average) figure for line attenuation wasn't appropriate for VDSL2 since attenuation is frequency dependent.

But whoever built the Huawei firmware and specifically the middleware that sits between the webserver and the xDSL driver, didn't update the MIB references to point to the right MIB variables.

Broadcom's confidential source code for the ADS2+ driver was accidentally published last year, so you can get a good idea of what happens under the bonnet with the 63xx xDSL driver. Unfortunately, noone to date has leaked the source code modifications for VDSL2, otherwise the attenuation bug could be patched once and for all.

It's possible to hack together a patch by modifying the ASP code in the Huawei's web interface so that the attenuation figures for a VDSL2 connection are retrieved from a different source (from the response to a 'pbParams' request made to xdslcmd, a tool in the firmware).   That's a bit of clumsy solution, though.

Cheers,
a
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on October 04, 2011, 07:28:10 PM
Hi
Thanks for the very  informative reply  :)
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 04, 2011, 07:57:53 PM
Hi
Thanks for the very  informative reply  :)
Regards Jeff


& just what I was going to say  ;D

According to Plusnet, I now have a perfectly acceptable Profile Name of 7.5Mb-15Mb.

That seems quite good for an "Up to" 40Mb service, from a cabinet situated just a few hundred yards from my home ???

I might post Plusnet's full response to my recent & drastic downturn in both DS & US speeds later on, (if I can be bothered).


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 04, 2011, 08:09:05 PM
Quote
I might post Plusnet's full response to my recent & drastic downturn in both DS & US speeds later on, (if I can be bothered).

Paul,

You must be bothered enough to make the posting otherwise you are giving a tacit signal that "they" have won. >:(

There is an option to consider, at this stage. Request a MAC code from PlusNet and then join Andrews & Arnold. The latter CP / ISP enjoys, nay, relishes fixing the problems that other CPs / ISPs can't (or won't attempt to) fix. :-X
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on October 04, 2011, 08:16:01 PM
I have read this thread with interest and there is one thing that stands out.
Quote
However, they say that as my line faults were "fixed", & I was achieving download speeds higher than the estimated 15 Mbps, there is nothing they can do to report a fault to BT:-
That absolutely stinks of the old upto 8megs. I know we are talking higher figures with the FTTC but the mention of achieving what they (Plusnet owned by BT) feel is an acceptable connection rate. I would say you are on an uphill struggle to improve things. It's like trying to run through treacle once things like that get mentioned.
If Walters suggestion works then it will be wonderful, however I doubt very much that you will get any favourable response as it will leave the door wide open for anyone in the same or similar situation contacting the person mentioned.
Good luck all the same.
From my first post on this thread. Sorry but I had an idea it would come to something like this.
I had a very similar experience with BT, albeit upto 8megs. This IP profile rubbish finished me with BT for good on broadband. Kept the landline and changed to LLU on adsl2+.

burakkucat's idea sounds like a good way to go.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 04, 2011, 10:40:56 PM
Hmmmmmmm

I'll mull all this over & decide what to do tomorrow.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on October 04, 2011, 10:50:41 PM
Hi
Plusnet is this the some "honest  Yorkshire broadband "

Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: silversurfer44 on October 05, 2011, 07:49:57 AM
>> Plusnet is this the same "honest  Yorkshire broadband " <<

No it is now part of the BT conglomerate!!!

No longer independent.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 05, 2011, 07:51:06 AM
Hi
Plusnet is this the some "honest  Yorkshire broadband "

Regards Jeff

Nearly Jeff.

Their adverts say "GOOD HONEST BROADBAND FROM YORKSHIRE"

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 05, 2011, 01:45:52 PM
Dear Readers,

I now have mulled this matter over for a while.

Unlike Plusnet & BT, I have collated factual data (not supposition, "likely" scenarios, & completely false information), from both before & after I had access to an unlocked modem's statistics.

I have briefly summarised the various issues into 1.5 sheets of A4 paper, & added backup charts, graphs, & tabulated data.

Seeing the information graphically presented, it is vey clear to me that I enjoyed high speeds & stability for more or less a full month before my phone & broadband services were completely cut off for a 4 day period starting 21st July.
Nobody has ever confirmed what actually caused this unexpected loss of service.

& as far as I am concerned, nobody has ever convinced me that it has ever been fully fixed.
I believe my data clearly & undeniably proves that point.

From that date right up to today, the factual data clearly demonstrates a low speed connection (very low for periods) with much instability.

The whole document is too large to post in this forum so I will find somewhere to locate it & provide a link for you to read it & pass any suitable/helpful comments before I send it to the relevant levels of Plusnet's & BT's management tiers.

I also fully intend to publicise the outcome along with my findings as widely as possible.

I am still fully prepared to accept that matters have not yet been resolved due to the learning curve that both Plusnet agents & BT engineers are still clearly climbing.
I will also fully publicise a successful outcome (if there should be one).

Watch this space for the link to the document.
I hope to provide it some time this evening

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on October 05, 2011, 02:04:03 PM
Hi
Good for you . Wish you lots of success. :)
Regards Jeff
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 05, 2011, 07:56:45 PM
Dear All,

Here is the link for the draft Summary document:-

https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0B7Kcea04kkOEZDYyZDkzMGEtM2Q4OC00NzY2LTgxNWUtNGVhZTQyMjZkZmM2&hl=en_US

Please feel free to comment / slate it to bits.

I would really appreciate your feedback on whether it makes sense, appears factually well founded, & clearly proves that I did have a good connection for almost a full month, & that since the total loss of service, the data/chart/graph proves there is still a physical & repairable fault somewher in the connection between the cabinet & my house.

I need to re-engage Plusnet to pursue a resolution to this matter as they appear to have given up on me now.

As they confirm they have no real data to work with, I am struggling to understand how they can state that my connection is within acceptable limits.

Does 12Mb download speed really appear within acceptable limits for an up to 40Mb service that did deliver 30Mb for a while, despite the pre-install estimated 14.6Mb that nobody appears to be able to confirm EXACTLY what it was based upon?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Oranged on October 05, 2011, 11:07:00 PM
Are your speed tests performed via ethernet or wireless ?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 06, 2011, 01:05:08 AM
Paul,

For the July 21st to 26th incident, have PlusNet provided you with a copy of the OR engineer's report? Sight of that will show exactly what work was done and thus, from that, what caused your service outage. ???

[Completely OT but b*cat notices that this is his 2^9 th posting in the fora.  :)  ]
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 06, 2011, 05:54:43 AM
Are your speed tests performed via ethernet or wireless ?

Always via ethernet from my destop PC that is located aproximately 1m away from the BT modem & master socket, which used to be an extenion & was converted to a master by the installing engineer.

The wireless laptop is a good distance & 2' thick walls away from the modem & router, so is never used for speed tests.

The wiring from the point of entry to the master socket is high quality shielded twisted 2 pair cable. 1 pair goes directly to the master & the other pair goes off to my phone extensions.

Every visiting engineer has checked the internal wiring & socket & I ran my connection for a few weeks with the extension wiring disconnected.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 06, 2011, 06:00:06 AM

For the July 21st to 26th incident, have PlusNet provided you with a copy of the OR engineer's report? Sight of that will show exactly what work was done and thus, from that, what caused your service outage. ???


Hi b*cat,

Nope, other than it was an external fault that has been fixed.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 07, 2011, 10:00:31 AM
Hi Folks,

Just waiting for another update from Plusnet regarding my response to their very recent statement that any futher investigation has now ceased as my connection is within acceptable limits compared to my pre-install estimate, with NFF (no faults found???)

BTW, does this sound at all vaguely familiar? :-

http://community.plus.net/forum/index.php/topic,99006.0.html

Bob Pullen from Plusnet said "I'm not sure I'd consider 19Mbps to be a 'poop speed'"

I consider 19Mb to be 'poop' compared to the 37Mb that the poor lad WAS getting.

Paul.


EDIT:
Why on earth has this thread reached page 23?

The issue is simple.

I had a really stable, high speed connection.

BT carried out some "work". I don't know what it was, or who it was for.
The result was that I lost both my phone & broadband services for 4 days.

BT supposedly fixed the fault that THEY had caused.

Ever since then, my connection has been quite unstable & my speeds have been low.

BTW, Plusnet have recently advised me to take this matter up with Ofcom and/or use their own complaints procedure as they intend to do nothing else to resolve it.
I thought I was paying Plusnet for phone & broadband services that they would fix when they break.

Still awaiting a response regarding their NFF message.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 07, 2011, 05:31:49 PM
<snip>

I had a really stable, high speed connection.

BT carried out some "work". I don't know what it was, or who it was for.
The result was that I lost both my phone & broadband services for 4 days.

BT supposedly fixed the fault that THEY had caused.

Ever since then, my connection has been quite unstable & my speeds have been low.

<snip>

Perhaps the "Big Chief"'s office should be made aware of this debacle -- how two subsidiary organisations (OR and PlusNet) of his group (the BT Group) have dug themselves into a pit and, due to what seems to be silly pride, refuse to stop digging. In essence, the ports of the DSLAM in the fibre cabinet should be delivering 40 Mbps downstream and not 22 Mbps. If the DSLAM is faulty, it should be replaced. Too much obfuscation has been attempted by OR and PlusNet. Shame on them both.

The Big Chief (http://www.btplc.com/Thegroup/Ourcompany/Theboard/IanLivingston/IanLivingston.htm). His office contact e-mail address: Ian.Livingston@bt.com
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 07, 2011, 05:59:38 PM

In essence, the ports of the DSLAM in the fibre cabinet should be delivering 40 Mbps downstream and not 22 Mbps. If the DSLAM is faulty, it should be replaced. Too much obfuscation has been attempted by OR and PlusNet. Shame on them both.


Thanks for the contact details b*cat.

One of my problems is that until quite recently, whenever BT's engineers referred to the cabinet, I took it to mean the fibre cabinet as I have a FTTC service.
It actually transpires that they mean the old cabinet (at the other end of the patch cable from the FTTC cabinet).
I have discovered that the OR engineers that have visited me are not actually allowed inside the fibre cabinet.

As the DSLAM & DLM equipment are located inside the fibre cabinet, DLM will have had its wicked way with my connection before the end of the patch cable at the old cabinet.

Now, when the L & S was carried out, I was promised the equivalent of a new connection, thus allowing DLM to have its way, & for my connection to retrain from 40Mb right from the start.

It has not been confirmed, although I have asked a few times, whether my connection was re-set at 40Mb following the L & S.

As stats & graphs from my unlocked modem, collected immediately after the last engineer left my home, suggest that was NOT the case, is it any wonder that my speeds have not & WILL NOT return if my starting speed is not much above 20Mb.

I have tried my hardest to explain these matters to Plusnet, to no avail (despite me providing plenty of sufficient evidence).

Alongside the low starting speeds is the potentially ongoing issue regarding my line's instability since I lost services for 4 days.
e.g. last weekend, when "something" caused my modem to re-sync at below 10Mb while I was still tucked up in bed.
My download speeds were obviously lower than the sync speed.

I not allowed to talk to BT, Plusnet have refused to talk to BT, will Ofcom really talk to BT on my behalf?
Probably not a b*cat in hell's chance.

Have the big guys squashed the little guy yet again?
Not without a fight they haven't.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 07, 2011, 10:39:44 PM
Quote
One of my problems is that until quite recently, whenever BT's engineers referred to the cabinet, I took it to mean the fibre cabinet as I have a FTTC service.
It actually transpires that they mean the old cabinet (at the other end of the patch cable from the FTTC cabinet).
I have discovered that the OR engineers that have visited me are not actually allowed inside the fibre cabinet.

Yes, I appreciate that fact, Paul. When you next travel down Heywood Lane, stop and take a look at the locks on the original PCP and its fibre pairing. You will see that the PCP and one section of the fibre cabinet have triangular "heads" to the lock bolts, whilst the electronics side of the fibre cabinet has star "heads" to the lock bolts. A POTS network engineer or a broadband CSE will only have a "triangular" key and, according to a discussion I had with Mr Pag, even a broadband SFI CSE such as himself is not supposed to open the "triangular" side of the fibre cabinet.

For good measure, you might as well give both cabinets a good kick -- it is strange the effects to which modern electronics will respond. >:D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 08, 2011, 12:18:25 AM
@ Paul,

I have been thinking about your lamentable situation re the best method of obtaining a satisfactory outcome.

I think we must assume that PlusNet do not want to consider the invaluable technical evidence you have provided to assist them in their dialogue with BT Openreach.
There is perhaps a slim chance that the BT Group might see that this is very bad negative publicity. Very sadly, if not rectified, it demonstrates a monumental investment blunder that the BT Group have made in attempting to continue with the GPO's Public Switched Telephone Network.

Perhaps to you, as an individual, the latter is of little consequence and does nothing to improve matters for the service you are paying for. In these circumstances, perhaps the only remedy is one of shrewd patience. I.e maintain an accurate record of the bRAS figures and BT speed tests to demonstrate the unacceptable unreliability of your service. After a suitable time has elapsed you present this data both here, to PlusNet and to your MP and local Government representatives as broadband has become a political topic. (I am reasonably sure Ofcom will have no interest in an individual's case.)

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jelv on October 13, 2011, 10:22:23 AM
Have you considered discussing your issue with Andrews & Arnold (http://www.aaisp.com/broadband-trial.html)?

Quote
We pride ourselves in having a very capable team of people that deal with faults. We have a close working relationship with BT, and our team are well known within all parts of BT for not tolerating being fobbed off.

If they managed to get it sorted you could really rub PN's nose in it!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 13, 2011, 01:53:10 PM
Have you considered discussing your issue with Andrews & Arnold (http://www.aaisp.com/broadband-trial.html)?

Quote
We pride ourselves in having a very capable team of people that deal with faults. We have a close working relationship with BT, and our team are well known within all parts of BT for not tolerating being fobbed off.

If they managed to get it sorted you could really rub PN's nose in it!

I have indeed considered AAISP.

However, I am only a few months into a long Plusnet FTTC contract, with early termination costs etc.
(Mind you, Plusnet would probably pay ME to walk away now) :lol:

I still have every faith that Plusnet will manage to get BT to resolve this simple issue:-

My connection was brilliant.
BT carried out some work, for someone, somewhere, that left me without a connection for 4 days.
My connection has been variously unstable & slow ever since its reinstatement.
BT and/or Plusnet keep referring to my pre-install estimated speed of only 14.6Mb, despite me achieving high speeds right up to BT's "accidental" disconnection.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: camallison on October 13, 2011, 04:59:01 PM
My son experience a very similar problem earlier this year which, after much to-ing and fro-ing has now been solved.  It turned out to be a severed connection in the last mile coppers that had been hurriedly twisted back together by (the culprit) whoever severed them in the first place.  Surprise, surprise - British Gas (or their contractor) had done some mains repair work in their street.  Once the BT contractor had dug down to where the fault was detected to be, a bundled "repair" was found with gaffer tape around it to "keep out the damp".  The (multiple core) cable was then correctly terminated and properly insulated and reburied.  Result - fault totally cleared.

Had any gas or water mains work in the neighbourhood recently?

Colin
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 13, 2011, 05:31:40 PM

Had any gas or water mains work in the neighbourhood recently?

Colin

Hi Colin (camallison),

I am not aware of any "other" work being carried out by other statutory undertakers at that time.

From the limited information I have at hand, it would appear that BT accepted responsibility for the loss of service, but will NOT accept responsibility for restoring my connection to its original condition.

Feedback from Plusnet only this afternoon (via Alex Rolls) indicates that as far as they are concerned, the matter is now closed.

Despite previous denials from various Plusnet agents, Alex also confirms that FTTC speeds,  following the training period, usually diminish - quote:- "as we see this phenomenom with most of our fibre lines"

He also only now confirms (after 2 months of hassle) that "We also saw this throughout the FTTx trial".

I was led to believe the training period was 10 days & then MSR (maximum stable rate) & FTR (fault threshold rate) were established.

It now appears that the training period for FTTC can be up to a month.
Well, at least that's how long my connection provided stable & high speeds.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 13, 2011, 08:22:40 PM
Shame on PlusNet. >:(

Shame on OpenReach. >:(

The time has come to make a written request (paper, envelope and stamp) to PlusNet's registered office for a copy of the engineering report that was dawn up as part of the documentation of the repair process from when OpenReach resolved your four days without any telephony or Internet service. :-X
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 13, 2011, 10:44:59 PM
Shame on PlusNet. >:(

Shame on OpenReach. >:(

The time has come to make a written request (paper, envelope and stamp) to PlusNet's registered office for a copy of the engineering report that was dawn up as part of the documentation of the repair process from when OpenReach resolved your four days without any telephony or Internet service. :-X

Hi b*cat,

Plusnet's comment from the day the disconnection was reported:-

"NDT

Test Result: Fail - Fault located in local network
Description: FAULT - Earth Contact"


Just for my own "entertainment", I thought I would take a look at some old Plusnet documentation, just to see whether my memory had been playing tricks on me for the last 2 months, & to see how it compares to Alex's latest comment.

It might just be the way I was reading it because it appeared to contradict Alex's comment.
So I highlighted some of it in red & made it a bit bigger to help me see it a bit more clearly.

From my Value Fibre Welcome pack:-

Your first 10 days of broadband

At first we won’t know exactly how fast your broadband will be. During the first 10 days you’ll see your speeds
go up and down. You might even get disconnected from time-to-time. Don’t worry though, this doesn’t mean
you’ve got a problem, so please bear with it. This period is where we find the best balance between speed
and reliability. In a few days it’ll settle down for you.

Tip: You can use the Broadband Fault Checker from any Internet connection. This means you don’t
have to use your own, you can tell us about a fault from a friend’s house, the library, or from work.

Why am I not getting maximum speeds?
The maximum speed is the theoretical maximum possible based on ideal conditions. The length and quality
of the phone line between your house and your local exchange all affect the speeds you can get. The broadband network will adjust your line speed to be as fast as possible without becoming unreliable.

My broadband speed has suddenly dropped. Why?
A temporary fault on your telephone line, even some dodgy British weather can cause your speed to drop, as
we try to keep your connection stable. Once the problem has passed you’ll see your speeds go up again.If your speed doesn’t go back to normal after 3 days, try switching your modem or router off and on again, once a day for about 5 days. This forces the network to get your line’s highest speed.


Nope, that didn't work. It still seems contradictory to me.
It also seems strange for Plusnet to state they didn't know how fast my broadband would be, but now I have a genuine problem they refer me back to a pre-install estimate.

I also obviously incorrectly assumed that a month's stable & high speed connection was undeniable proof of what my connection could (& did) achieve & also proof that my line must have been in much better condition then.

Oh, well.....

Hmmmmm....................


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 14, 2011, 12:10:54 AM
What do I find laughable in the PlusNet information that you have shown us, above?

Quote
The maximum speed is the theoretical maximum possible based on ideal conditions. The length and quality
of the phone line between your house and your local exchange all affect the speeds you can get.

As the service is FTTC, we must assume that the two sentences I have just quoted was written by a numpty. The seven words that I have underlined for emphasis . . . Oh, dear.  :lol:

Quote
NDT

Test Result: Fail - Fault located in local network
Description: FAULT - Earth Contact

That is the result of PlusNet's own testing. It would be interesting to read the report from the OpenReach engineer who fixed that fault -- because that is the start of all your troubles.

The other thing that still needs to be addressed is why the cabinet's DSLAM is only providing 22 Mbps downstream. Remember, 24 Mbps is the theoretical maximum for ADSL2+.  Until the DSLAM provides the full 40 Mbps downstream, you will only receive 55% of the actual speed your line is capable of supporting.  :o

Perhaps you should only pay PlusNet 55% of what they are charging you?  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 21, 2011, 01:36:22 PM

I still have every faith that Plusnet will manage to get BT to resolve this simple issue:-

My connection was brilliant.
BT carried out some work, for someone, somewhere, that left me without a connection for 4 days.
My connection has been variously unstable & slow ever since its reinstatement.
BT and/or Plusnet keep referring to my pre-install estimated speed of only 14.6Mb, despite me achieving high speeds right up to BT's "accidental" disconnection.

Paul.



Hi Folks,


Not much has happened since my last chapter in this epic tale. Hence ny absence for a while.

However, in the last day or so, BT's & Plusnet's FTTC availability checkers have both started reporting increased estimated speeds for my connection.

The 14.6MB estimated speed that Plusnet keep quoting as the threshold before a fault can be raised with BT has now increased to 24Mb.

Unless someone moves the goal posts again, I will indeed refer to my new estimated speed in any communications (as I have indeed already done this morning).

Poor old Alex. I really do feel sorry for him.

Also, it appears that BT have now started to roll out the new 17a FTTC profile as a replacement for the original 8c profile.

I believe the new profile will be using even higher frequencies, which may be a bit of an issue for my heavily attenuated or speed capped connection.
However, I believe there will also be a "power" boost for the new frequencies to offset some of the line loss.

I don't yet know when/if I will be switched to the new profile, but I have seen evidence of a recent user's switch that has increased his speeds by quite a few Mb.

Of course, none of that addresses the fact that my connection was very good until BT engineers ruined it & now it is not so good (to put it incredibly politely).

Watch this space for the next installment.

TTFN.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 21, 2011, 07:26:03 PM
Quote
Of course, not of that addresses . . .

sed 's/not/none/'  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 21, 2011, 08:56:33 PM
Quote
Of course, not of that addresses . . .

sed 's/not/none/'  ;D

touché  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on October 22, 2011, 12:40:12 AM
touché  :)

Ouch! Did someone just peck at my tail? :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 22, 2011, 12:53:32 AM
Ouch! Did someone just peck at my tail? :-\

Haha. Not at all.

Completely OT, but it appears that I have recently been made the guardian of my son's large black tom cat, as pets aren't allowed at his new home, & I am very "cat friendly".

Paul.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: jeffbb on October 22, 2011, 07:03:37 PM
25TH anniversary coming up :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 28, 2011, 06:54:27 AM
25TH anniversary coming up :lol:

& to celebrate the fact, BT have changed my FTTC profile from 8c to 17a, with a SLIGHT speed increase.
Still not resolved the high attenuation by the looks of it though (unless I still have a capped IP Profile).

(http://www.speedtest.net/result/1559672309.png) (http://www.speedtest.net)

So, it might now be time to speak with Mr. Rolls at Plusnet again.

Current stats attached

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: alexrolls on October 28, 2011, 01:27:08 PM
Hi Bald_Eagle1,

Your support ticket has been updated. ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 28, 2011, 05:28:48 PM

Your support ticket has been updated. ;)


Cheers Alex,

& Likewise, I have updated your update.

I missed the chance to reboot the modem when SNRM was "good" this afternoon as I was a bit later than expected getting home from work. So I'll try it another day.

FYI, SNRM has dropped rapidly from almost 7dB, to just 4 dB in about 15 minutes or so.

No doubt that's due to all the women getting home from work & switching their cookers on to get tea ready for the man of the house, & switching the heating on to warm his slippers next to the radiator.
No sexism intended, but as a Yorkshire based lad, you must know where I'm coming from  ;)

Paul

P.S. I do hope that Alex isn't short for Alexandra.

P.P.S. I know it's not really, as we have spoken on the phone a couple of times.

P.P.P.S. The CRC, FEC & HEC error count has stayed very low for a change too (1273, 48, & 246 respectively over 11 hours or so connection time).
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: gouledw on October 30, 2011, 08:53:33 AM
If this thread is about estimated speed on FTTC... Then what am I likely to get on my 9km line as I already get 2meg (stable) and the cabinet is 7km from me? And vDSL deteriorates the speed 4x quicker per km than adsl?

General Information

DSL Line (Wire Pair):   Line 1 (inner pair)
Downstream Rate Cap:   2272 kbps
Downstream Atten. at 300kHz:   81.0 dB
Uncancelled Echo:   -16.2 dB   Ok
VCXO Frequency Offset:   -34.3 ppm   Ok
Final Rx Gain:   29.9 dB   Ok
Excessive Impulse Noise:   0   Ok
Downstream Required Impulse Noise Protection:   4
Downstream Impulse Noise Protection:   0.00
Downstream Delay of Latency Path:   0.25 ms
Upstream Impulse Noise Protection:   0.00
Upstream Delay of Latency Path:   0.25 ms
Framing Mode   ATM
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 30, 2011, 11:14:25 AM

If this thread is about estimated speed on FTTC... Then what am I likely to get on my 9km line as I already get 2meg (stable) and the cabinet is 7km from me? And vDSL deteriorates the speed 4x quicker per km than adsl?


Hi gouledw,

I am probably not the best placed person to accurately answer your question, as I started this thread, asking the same question, & still don't know the answer.
Nobody does, even BT!

What does BT's Infinity availability checker state as estimated FTTC speeds for your phone No., and/or Post code?

If the FTTC cabinet really is 7km distant, I would be very surprised if FTTC would be available for you at all.

From what I can gather, if it was available over that distance, I understand the speed would be somewhat similar (possibly worse) than ADSL, therefore not at all worth the increased cost anyway.

Where did you obtain your reported distances from the exchange & cabinet?


& 81.0 dB attenuation seems really high.
Are you really getting 2Mb throughput?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: gouledw on October 30, 2011, 11:42:37 AM
Hi Bald_Eagle1

Well its a long story, and I will not go into lengthy details.  But for the last 5 years we've had loads of trouble with noise on the PSTN.  And finally after switching ISP's 9 times last year we came back to BT Retail beginning of this year, I immediately e-mailed off an e-mail to the CEO of the group, who then intern passed it to his secretary.  Well they spent about 2 months just testing different parts of the cable to see what was wrong with it.  And in total about a third of the line was duffed (3km of it!).  So they set out replacing different parts of it in an attempt to cure the noise.  But in the end they found that no matter what part of the line they replaced there was always some part that was causing noise.  It didn't help the fact that it was all mostly DIG armoured cable.  But while they were upgrading the cable they decided it would be worth replacing each section of cable with some .9 cable as at different stages of the line there were around 50+ premises or so.  But ....... 7 months later we've had the job done and all the cable is the nice thick .9 stuff bar the last 200m to the house which is DROPWIRE12.  And its also been a combination of getting the right things replaced on my side of the NTE5.  I rid away with that useless NTE2000 filtered faceplate, and replaced it with an ADSL Nation, simply as it has better and more components in it (all to get a Thunderstorm the next week and a 20,000 volt surge) luckily all it fried was the router, so that was all completely fine.  And then having all the internal wiring replaced with a white external speck cable, and also having an RF3 junction box placed before the Master.  Getting new routers and playing about with different ones, and then eventually once we'd found the right one, because the 2700HGV was just syncing to high (3072kbps) on a 6dB margin and dropping out all the time, I turned to a fixed rate and also another Business Hub the 2701 in order to quell the speed a bit.

For instance my socket how I have tidied up, I don't know how much difference it makes, not a lot I would presume but maybe razpag can advise?

And also on the checker nothing comes up, and can't place an order under EcoPlus.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on October 30, 2011, 12:06:35 PM
& I thought that I had experienced a few trials & tribulations!

If your line length is indeed 9km from the exchange, I would imagine you are currently achieving the best you can get.

My ADSL line length from the exchange was reported as 5283m, & I could only achieve around 1Mb until switching to FTTC.

Are you 100% certain that the nearest FTTC cabinet is no closer than 7km?

If so, there's not really anything I could suggest other than MAYBE a mobile phone broadband dongle, or satellite (really expensive?), but I'm not quite sure what their max download speeds are, or if like me you have poor mobile phone coverage, probably not worth trying anyway.

If you have read any of this epic thread, you will also have gathered that FTTC isn't exactly a fully understood technology (yet).
Either that, or it IS understood, but conveniently ignored on occasions.

Unfortunately razpag is no longer a member of this forum & his hands-on BT engineering installation experience & knowledge is very sadly missed.

I'm sure other members will drop by at some stage & will be able & willing to comment on your wiring photo though.

I'm sure he won't mind the mention here, but waltergmw has a great deal of experince with problematic lines & even assistance in getting connections into remote locations.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: gouledw on October 30, 2011, 12:17:25 PM
Im perfectly happy with speed I get considering distance to the exchange.  And it wouldn't have helped if I didn't have my friend in BTw ;) And the OR man said it was 7km, because thats how far it is between me and the nearest local village...
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on October 31, 2011, 07:32:15 AM
Hello GouleDW,

You are exceedingly lucky to have an attenuation as low as 80 dB if you have such a long line.
80 dB is just about the maximum value to obtain a stable connection as the laws of physics, even with probably the best modem, are difficult to circumvent.

Your master socket looks quite new and in dood condition.
You might try disconnecting the extension and using a cordless DECT phone with the base station sited well away from the master socket.
Using a short shielded twisted pair RJ11 modem lead sometimes has a marginal effect too.

Failing this a wireless link back to somebody closer to the exchange is probably the only other option.
E.g.  http://forum.kitz.co.uk/index.php/topic,9625.msg195241.html#msg195241

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: GunJack on November 01, 2011, 05:19:46 AM
what happened to razpag, where'd he go, why ??  Have I missed something ??
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: tuftedduck on November 01, 2011, 06:21:28 AM
Razpaq decided that he could no longer contribute to the Forum, and requested that his account be deleted.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: GunJack on November 01, 2011, 02:41:54 PM
Razpaq decided that he could no longer contribute to the Forum, and requested that his account be deleted.

That's a shame, his on-the-job knowledge was highly regarded :(

Don't suppose it was anything to do with his line management chain sussing who he was and applying pressure at all ???
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on November 01, 2011, 06:08:23 PM
Razpaq decided that he could no longer contribute to the Forum, and requested that his account be deleted.

That's a shame, his on-the-job knowledge was highly regarded :(

Agree / agreed. Most definitely. With Ezzer retired from the job and now emigrated, Mr Pag would be significant contributor to these fora.

Quote
Don't suppose it was anything to do with his line management chain sussing who he was and applying pressure at all ???

No. It was, unfortunately, the result of a personality clash in the early part of last September. :'(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 09, 2011, 06:25:19 PM
Hi Folks,

As they say, in a rather un-PC manner, "It's not over until the fat lady sings"
Well, I don't hear any singing just yet.

Another engineer's visit is now being arranged via Plusnet based upon the details in this thread:-
http://forum.kitz.co.uk/index.php/topic,10142.msg204066.html#msg204066

Watch this space (& that space) for any updates.

Without the "evidence" from the various stats collection & graphing scripts, I would simply not have reached this stage.
So, thank you again to those people, along with thanks to those who have provided me with other technical & factual details.

My connection looks rather "messy" from this afternoon's stats.
It's almost as though someone (unnamed for now, but I'm sure we all know who it was) scripted the production of stats collecting scripts, just in the nick of time  ;)


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 15, 2011, 02:48:01 PM
Hi Folks,

Update from this morning's Engineer's visit.

On arrival, the Engineer confirmed he had spoken with someone at his end so he had a rough idea of the issue(s).
That was a refreshingly good start.

He tested sync speed at the master socket with his JDSU & said it was 24Mb, attenuation about 22dB, & line length 1 km.
Earlier on this morning my modem had been reporting 25.3 Mb.

He wasn't too happy about my "high quality, high speed, twisted pairs shielded cable" that the original installation engineer had wired to the incoming pair (upstairs) to make the new downstairs master socket.
Neither was he happy that from the new master socket, it had been "back-wired" to create the upsairs extension (at what was the old master socket position).

He disconnected everything from the incoming pair upstairs, clipped on an adapter cable & tested sync speed there.
He said it was 30Mb, i.e. a 6 Mb increase from downstairs.
His deduction was that the shielded cable must have been the problem all along.
Hmmm........

When I reminded him that I been actually downloading att 33 Mb for the first month on the old 8c profile, he said that's how it works over D-side lengths similar to mine.
i.e. It starts off at high speeds & stabilises down after a while.
He also said it can take much longer than the 10 day trining period to find the right balance between stability & speed.
Hmmm...........That's not quite what Plusnet have told me, or what I have read in other forums.

Anyway, he went off to the cab to "check things" there.

On his return, he confirmed that 40 Mb was present at the cab.
He also confirmed that he had tested the speed after applying an attenuator, which resulted in 30Mb at the cab.
He did say that the attenuator had slightly more attenuation effect than my D-side cable's own attenuation.

He decided to rewire everything from the incoming supply.
Thinking he was going to route a cable through the house, I started clearing space for access.
The next thing was I heard him putting up a ladder & saw him fixing a new drop wire round the back of the other half of the semi-detached house.
He had already obtained approval from my neighbour to do this.

Not only did he provide new cable to the nearest pole, he got a cherry picker organised & took the cable right across the main road to the next pole (probably around 100m in total length).

He brought the new cable in through the back of my house (downstairs) & replaced the whole master socket.
He then reused my shielded cable to provide the connection back to my upstairs extension.

Sync speed was tested again.
I THINK he said it had gone up to 28Mb or so & that it was a lot better than when he had arrived, which proved it must have been the shielded cable causing the issue(s) all along.

I asked if he needed to get the BT Fibre Centre to reset my profile just to finish off the "repair".
He said that wouldn't be necessary any more as his engineers' notes will deal with that sort of thing.

He also said that undoubtedly, the 4 day complete loss of service had had an effect & that now everything was right again, it might gradually build up speed again.

He reconnected the modem & we had a quick look at the stats & tested the effect of using the phone.

The modem reported:-

DS Attainable Rate 33136 K
US Attainable Rate 5560 K
DS Sync speed 27400 K
US Sync speed 4999 K
DS SNRM 6.3 dB
US SNRM 7.1 dB
DS Output Power 12.2 dBmV
US Output Power 6.3 dBvM

CRC Errors US & DS 0
FEC Errors DS & US 0
HEC Errors DS & US 0

Picking up the phone & making a call had only a tiny effect upon SNRM, & didn't cause any errors.

(http://speedtest.net/result/1593225920.png)


In other words, everyting looks a bit better than of late, but still not what it was for the first month.

Was it the shielded cable, or the old cable/joints between the telegraph poles, or the master socket/filtering?
I will obviously monitor matters for the next few days/weeks.

After being reconnected for roughly 2.5 hours, SNRM has dropped (only a little) & DS CRC errors now total only 6, FEC errors 5 & HEC errors Nil.


Paul.

The graphs are attached......

Edit:
I musn't forget to add thanks to Plusnet (Alex R in particular), for not just fobbing me off with this matter.
It's not over until the fat lady sings, but at least I think I am now beginning to hear her loosening up her throat in readiness.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on November 15, 2011, 06:25:35 PM
Hmm.  :hmm:

Very interesting. So if the original installing engineer had not attempted to use what he had found in situ but had provided a new feed to a new NTE5/A, this whole saga may have been avoided.  :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: UncleUB on November 15, 2011, 07:01:30 PM
Only need 5 more pages and this thread will be available on Kindle  :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 15, 2011, 10:05:37 PM
Hmm.  :hmm:

Very interesting. So if the original installing engineer had not attempted to use what he had found in situ but had provided a new feed to a new NTE5/A, this whole saga may have been avoided.  :-\

Hmm indeed  :-\

I'm not too sure about that.
The original installing engineer did manage to get me over 30 Mb download speeds for a month, & everyone else that I am aware of on similar speeds has seen a few Mb increase toward the maximum out of the capped 40Mb service since the switch to profile 17a.

Although I was quite pleased to get a few metres of shiny new drop wire 10B & a new NTE5/A installed, along with the back-wiring removed, I have to say I was a little disppointed at the overall result.

My attenuation levels haven't changed much after today's visit & still seem very high.
I'm sure they can't have been that high when I was achieving the higher speeds or as one engineer has suggested in his personal & still unconfirmed theory, the service ran totally uncapped for the first month.

Is there still a HR or other issue somewhere in the copper?
Unless he did them at the cabinet, I am not aware that today's engineer carried out any TDR testing, so unfortunately I have no idea.
I meant to ask about that, but was distracted by my neighbour & unfortunately didn't come back to the subject by the time the engineer had packed up to leave.

We also spoke about potential issues on the E-side copper that is still used for my telephone.
The engineer said the E-side copper could not have any effect whatsoever on the D-side broadband, but that both E-side & D-side had been replaced during the previous "troubles" anyway.

Oh dear........
(http://www.speedtest.net/result/1594124016.png)

It's a long time since I saw such a low download speed.

Is the internet very busy tonight?
I tried a few different testers with very similar results.

I'll see how it looks during tomorrow, before perhaps trying a reboot.


Paul.


EDIT:

Immediate panic over:-

(http://www.speedtest.net/result/1594275719.png)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 15, 2011, 10:14:11 PM
Only need 5 more pages and this thread will be available on Kindle  :lol:

& what a fantastic Christmas present that would be, to have a new Kindle, complete with a pre-installed dramatic tale full of mystery & intrigue, with twists & turns throughout, leaving the reader begging for more  ;D


Oooh! I see we are another page closer now.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on November 16, 2011, 08:35:09 AM
Paul,

Very well done recording so much ("unapproved") information which may well be of great benefit to others.

Given the traumatic history on this line it is perhaps a pity that the engineer did not obtain the thicker dropwire 12 single pair cable.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 16, 2011, 09:11:02 AM
Paul,

Very well done recording so much ("unapproved") information which may well be of great benefit to others.

Given the traumatic history on this line it is perhaps a pity that the engineer did not obtain the thicker dropwire 12 single pair cable.

Kind regards,
Walter

Hi Walter,

The engineer didn't bat an eyelid when I showed him the modem's printed out stats/graphs and its actual web page interface.
In fact he seemed reasonably interested in what was shown, as a comparison with his JDSU readings.

I didn't really bother too much about obtaining the JDSU readings now that I can obtain all the details I need directly from the modem.

We still aren't sure how the JDSU combines the connection's attenuation levels into a single value.
I think the modem's attenuation values are more relevant anyway (split over the 3 different frequency band plans) as it highlights which frequencies are being attenuated the most.
In my case, the higher frequency band is attenuated that much that I get Diddly Squat from it (unlike users with much better speeds / quality of connection / genuine distance from the cabinet etc.

Alex R mentioned that my DLM profile is unusually not now shown in Plusnet's records (yesterday anyway).
He thinks this may be due to the connection going through another training period now that it has been "repaired" again.

BYW, I see that SNRM has started to gradually creep back up again from its overnight low of 4.2 dB. It is currently 4.7 dB.

It might be worth a re-sync/re-boot later on if this continues?
(We have both previously noticed that I have needed to reboot the modem to force an increase in sync speed, despite DLM automatically reducing it on the fly).

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on November 16, 2011, 10:24:15 AM
Hi Paul,

If you have the energy and the enthusiasm it would be well worth recording the JDSU comparison figures so you can "help" Openreach.
I know for a fact that at one time the engineers all knew that there was a reporting bug in the JDSU ADSL firmware.

If we carry on along this path the Kitz website might well become an enhanced training centre for BT openreach staff dealing with the mystical aspects of the VDSL implementation !

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 21, 2011, 10:26:35 AM
Dear All,

Just a quick update following the engineer's visit of 15th November:-

The connection now appears stable, & is now hardly affected at all by incoming/outgoing phone calls.
Sync speed has also shown a SLIGHT improvement, but is still well below its original level.

14 day, 24 hour, & this morning's graphs can be seen at this link ( too large to upload here without losing definition):-

https://docs.google.com/open?id=0B7Kcea04kkOENTc2NDdhOTctMTM0MS00MzUzLWIzMjYtMjYzMTRhYmU3YTZm (https://docs.google.com/open?id=0B7Kcea04kkOENTc2NDdhOTctMTM0MS00MzUzLWIzMjYtMjYzMTRhYmU3YTZm)


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on November 29, 2011, 01:10:12 PM
Howdydoody Folks,

Just a quick update:-

Since the engineer's visit of 15th November, my connection appears to be completely stable again (apart from the error count - more on that in my other thread at http://forum.kitz.co.uk/index.php/topic,10142.0.html

DS SNRM had been consistently running between approximately 4 dB & 4.5 dB with normal time of day fluctuations.
The modem had not re-synced since 18th November (some 11 days ago).
So, just for the hell of it, I thought I would force a re-sync this morning.

DS SNRM went up to 6.4 dB (now gradually tailed off to around 5.6 dB) & DS Sync speed went up slightly.

The outcome is that I am currently able to download at over 26 Mb for the first time since my 4 day (unexplained) loss of connection was restored toward the end of July.

(http://speedtest.net/result/1619041217.png)


My connection's DS attenuation still appears high though, which (to me) suggests there is still some sort of resistance somewhere in the D-side that CANNOT have been present when I was achieving the higher download speeds.
Either that, or there is a pysical cap on my connection's speed "somewhere".

I wonder if Plusnet are unwittingly capping my speed.
The engineer actually confirmed that 40 Mb was available at the cabinet this time, but Plusnet do appear to be possibly experiencing a minor glitch with their FTTC speed profile system, in that Plusnet's reported profile for some users who are solidly achieving maximum speeds, is lower than the default 37 Mb.

Mine has shown 37 dB, ever since I first noticed connection & speed problems. I wonder if it is somehow working in reverse, where Plusnet THINK they are letting me have the highest speeds, but in reality are somehow unwittingly restricing it.

Hmmmm. I'll have to ask Alex about that as he is aware of this "potential" issue to some extent:-

http://community.plus.net/forum/index.php/topic,100017.0.html


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on December 15, 2011, 10:23:30 PM
Ahhh,

Memories........................
 :( :( :( :( :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on December 16, 2011, 12:08:45 AM
Ahhh,

Memories........................
 :( :( :( :( :(

You've forgotten to include the "Rubbish_Speed_Test_Today", for comparison purposes.  :P
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on December 16, 2011, 05:46:56 AM
Ahhh,

Memories........................
 :( :( :( :( :(

You've forgotten to include the "Rubbish_Speed_Test_Today", for comparison purposes.  :P


Here's a couple of recent ones:-

(http://www.mybroadbandspeed.co.uk/results/127934091.png)

(http://speedtest.net/result/1650826570.png)


It did peak quite recently (but that didn't last for long before DLM had its wicked way with it):-

(http://speedtest.net/result/1638393380.png)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on December 16, 2011, 06:33:15 PM
Hmm.  :-\  Not good. Two out of the three equivalent to a relatively decent ADSL2+ service.  :-X

I would not be willing to pay my money for that.  >:(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on December 16, 2011, 08:57:12 PM
Hmm.  :-\  Not good. Two out of the three equivalent to a relatively decent ADSL2+ service.  :-X

I would not be willing to pay my money for that.  >:(

I don't really have a lot of options available to me.
I'm genuinely too far from from the exchange to gain any benefit from ADSL2+ at a much lower cost. So I could go back to 1 Mb to save the money.

Cable isn't available in my area.

Satellite is far too expensive.

It's too hilly in my area to consider wireless.

As FTTC is available, it's unlikely that FTTH will be rolled out any time in the near future.

Despite providing lots of factual evidence & statistics to the contrary, Plusnet are convinced my connection needs no further repair works & is as good as it ever will be.
Although each time an engineer has found & fixed a fault, I was told the same (LTOK).
It's just a pity that the engineers have never fully re-tested the connection after carrying out the work.

The only evidence I cannot provide is actual statistics from when my connection was obviously working well.
My attenuation levels for the various band plans is very high. That high, that I have gained diddly squat from the newer higher frequencies.
It surely cannot have been any where near so high when I achieved the decent speeds can it?

The real annoying aspect is that my decent speeds were achieved back in the 8c profile days.
Everyone else who was achieving a little over 30 Mb on the 8c profile now appear to be achieving the full Monty after the switch to 17a, or at least very close to it.

It now seems that I'll just have to live in hope that one day a BT engineer might accidentally fix whatever is wrong with my connection, just like a BT engineer accidentally broke it & left me with no services at all back in July.

It cannot just be coincidence that speeds & stability were pretty good before that accident, & have never returned since.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on December 17, 2011, 12:06:49 AM
@ Paul,

I am reasonably convinced that you are by no means the only one in that predicament.
It is time that Ofcom insisted that BT publish far more realistic figures. Something just has to be done to improve those like you, as well as those e.g. on the far side of our most aptly named Cobblers Brook !

Another solution would be to insist Ofcom makes the providers charge pro-rata so you would effectively get a discount for the lousy performance.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on December 17, 2011, 01:31:39 PM
Hi Walter,

@ Paul,

I am reasonably convinced that you are by no means the only one in that predicament.
It is time that Ofcom insisted that BT publish far more realistic figures. Something just has to be done to improve those like you, as well as those e.g. on the far side of our most aptly named Cobblers Brook !

Another solution would be to insist Ofcom makes the providers charge pro-rata so you would effectively get a discount for the lousy performance.

Kind regards,
Walter


It's not so much the cost, although a "discount" while a connection is under-performing would be nice (& possibly a slight incentive for providers to get it fixed).

It's more the issue that my line WAS performing very well, way beyond any 10 day training period (BTW, that apparently doesn't really apply to FTTC connections), but that it is now performning very poorly in comparison, yet nobody has any interest whatsover in "fixing" it as it is supposedly "within estimated speeds & specifications".

I have only today began to gather some "evidence" from other users on 1000m or so D-side connection lengths, where their attainable rates now peak at 44 Mb, giving sync speeds of 35 Mb:-
http://forums.thinkbroadband.com/fibre/t/4074867-re-long-line-fttc-question.html (http://forums.thinkbroadband.com/fibre/t/4074867-re-long-line-fttc-question.html)

& here:-

http://forums.thinkbroadband.com/fibre/f/4074344-bt-infinity-draytek-2750n-connection-issues.html#Post4074884 (http://forums.thinkbroadband.com/fibre/f/4074344-bt-infinity-draytek-2750n-connection-issues.html#Post4074884)

My Attainable rate is currently only 32012 K, with a sync speed of 27131 K.

My own sync speed WAS 35 Mb, even on the older 8c profile, & as my estimated speeds were 14.6 Mb as opposed to that user's 8 Mb, it suggests that I really am closer than 1000m to the cabinet.

I do believe that Ofcom, or somebody else, should FORCE BT into providing equipment where users can actually see their own connection's statistics, without the risk of falling foul of any breach of Ts & Cs.
The decision to INTENTIONALLY hide these stats by providing LOCKED modems is disgraceful, in my opinion!

It really is a whole load of Cobblers Brook  >:( >:( >:(


Paul
(A.K.A. Mr. Angry of Oldham)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Oranged on December 17, 2011, 04:14:12 PM

I do believe that Ofcom, or somebody else, should FORCE BT into providing equipment where users can actually see their own connection's statistics, without the risk of falling foul of any breach of Ts & Cs.
The decision to INTENTIONALLY hide these stats by providing LOCKED modems is disgraceful, in my opinion!


It could be construed as an unfair contract term associated with just the Infinity product because other broadband contracts allow such access.......but a contracts lawyer would need to be consulted on that one.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Maturecheese on January 22, 2012, 05:35:13 PM
I am roughly 600 meters from the cabinet (slight over estimate, I hope) and my estimated speed according to BT will be 27.7 mb.  Is this about right or is it quite slow and if it is slow for the length I can only conclude that the cable to the cabinet is aluminium :( as was hinted at by an engineer about 18 months ago.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on January 22, 2012, 06:18:05 PM
I am roughly 600 meters from the cabinet (slight over estimate, I hope) and my estimated speed according to BT will be 27.7 mb.  Is this about right or is it quite slow and if it is slow for the length I can only conclude that the cable to the cabinet is aluminium :( as was hinted at by an engineer about 18 months ago.

It's a little hard to say regarding your speed estimate.

In readiness for BT's speed doubling to 80Mb, they have stated that all speed estimates will be updated 28th/29th January.
However, it appears that some may have been updated already.

When I first got FTTC in June, my speed estimate was 14.6Mb. I achieved 32Mb - 33Mb (at first).

The FTTC profile has been gradually changed from 8c to 17a, again in readiness for speed doubling (more available higher frequencies & more available tones in which to load data bits.
I was switched to the 17a profile at the end of October.
Shortly after the profile swich, my speed estimate went up to 24Mb.
In the last couple of weeks, my speed estimate has gone up again, to 30Mb.

Most users with a relatively short distance (less than 800m) are currently achieving the full 40Mb.

Your estimate for only 600m does appear quite low, even if it is still based upon the old 8c profile.
I strongly suspect that aluminium cabling may indeed be a deciding factor in your estimated speed.

Most users, even on the old 8c profile, actually saw & have maintained much higher speeds than their estimates.
They even saw quite a substantial speed boost when switched to the 17a profile.

I would suggest you re-check your estimated speeds a few days after 29th January. It may increase.
Getting anyone to confirm whether or not it is currently based on the 17a profile will be nigh on impossible.

EDIT:
Have you noticed your estimated speeds changing over the last few months?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on January 22, 2012, 11:01:41 PM
Considering the approximate distance and the speed estimate, I have a feeling that there is a significant aluminium presence in the D-side wiring.

My neighbour, Gordon, & I have exactly 440 yards / 400 metres of copper D-side cabling and the attached image relates to his FTTC service. In particular, look at the data obtained from xdslcmd info --show (bottom right).
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Maturecheese on January 22, 2012, 11:10:17 PM
27.7mb is the estimated speed I have been given since I looked into getting FTTC.  I would say that was from roughly sept last year and It's still the same estimate.  I will find out from Tuesday on as that's when I'm getting it installed.  Incidentally, and I've mentioned this on here before, my next door neighbours line has a lower attenuation than mine, around 10 db lower even though her line goes to the same pole and no doubt the same cabinet. She gets a faster speed than me because of this. I raised this with BT and I got the usual reply, my line was performing above the minimum level required so no action needed.  I just hope that the reason for the poor performance of my line up until now is before the cabinet and not after it as the fibre to the cabinet will solve that. (fingers crossed)

EDIT  If the line is Aluminium then I'll just have to put up with slower speeds but it doesn't explain the discrepancies between my line and next doors as surely if mine is aluminium so is hers.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on January 22, 2012, 11:19:06 PM
Quote
I just hope that the reason for the poor performance of my line up until now is before the cabinet and not after it as the fibre to the cabinet will solve that. (fingers crossed)

If, by saying "before the cabinet", you are suggesting an issue with the E-side cable then, yes, the fibre optic link will replace that. The phrase "before the cabinet" is somewhat ambiguous, because it all depends from which vantage point you are looking towards the cabinet . . .

 :fingers:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on January 22, 2012, 11:25:49 PM
Incidentally, and I've mentioned this on here before, my next door neighbours line has a lower attenuation than mine, around 10 db lower even though her line goes to the same pole and no doubt the same cabinet. She gets a faster speed than me because of this.

Have you a means of discovering your neighbour's FTTC speed estimate as a comparison against yours?

Quote
I just hope that the reason for the poor performance of my line up until now is before the cabinet and not after it as the fibre to the cabinet will solve that. (fingers crossed)

Fingers crossed indeed. A 10dB difference in attenuation levels does appear to make a substantial difference for FTTC connections, speed-wise.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Maturecheese on January 23, 2012, 12:21:15 AM
Sorry I should have said the cable between the Exchange and the cabinet fingers crossed :)

I will check my neighbours FTTC estimate tomorrow, could be interesting.

EDIT  I have tried to check but as my neighbour is not with bt I cannot input the tel No and for some reason the checker won't accept house No and postcode.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on January 23, 2012, 12:25:34 AM
Sorry I should have said the cable between the Exchange and the cabinet fingers crossed :)

I will check my neighbours FTTC estimate tomorrow, could be interesting.

My next door neighbour's is the same as mine (30Mb)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on January 23, 2012, 12:28:37 AM
Quote
EDIT  If the line is Aluminium then I'll just have to put up with slower speeds but it doesn't explain the discrepancies between my line and next doors as surely if mine is aluminium so is hers.

Two adjacent properties with drop-cables from the same pole, which are fed via the same (aluminium) multi-pair D-side cable from the PCP. How can one pair have 10 dB more attenuation than the other? Possibly because of more (defective) joints. Aluminium is an amphoteric metal; it reacts readily with both acids and alkalis. Aluminium is actually a very reactive metal. It appears to be fairly stable and unreactive because of the thin film of aluminium oxide that rapidly forms on its surface. Now get two pieces of aluminium in contact with yet another metal & atmospheric moisture and the aluminium will readily corrode. If it is expected that an electrical signal, at radio frequencies no less, will flow through those two pieces of joined aluminium then there will be a severe degradation of the signal. It will be attenuated. If those two pieces of aluminium are sections of a D-side cable pair and the other metal is an old-style "blue bean" type of crimp, them I'm sure I don't need to type much more.  :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Maturecheese on January 23, 2012, 01:34:58 PM
Quote
EDIT  If the line is Aluminium then I'll just have to put up with slower speeds but it doesn't explain the discrepancies between my line and next doors as surely if mine is aluminium so is hers.

Two adjacent properties with drop-cables from the same pole, which are fed via the same (aluminium) multi-pair D-side cable from the PCP. How can one pair have 10 dB more attenuation than the other? Possibly because of more (defective) joints. Aluminium is an amphoteric metal; it reacts readily with both acids and alkalis. Aluminium is actually a very reactive metal. It appears to be fairly stable and unreactive because of the thin film of aluminium oxide that rapidly forms on its surface. Now get two pieces of aluminium in contact with yet another metal & atmospheric moisture and the aluminium will readily corrode. If it is expected that an electrical signal, at radio frequencies no less, will flow through those two pieces of joined aluminium then there will be a severe degradation of the signal. It will be attenuated. If those two pieces of aluminium are sections of a D-side cable pair and the other metal is an old-style "blue bean" type of crimp, them I'm sure I don't need to type much more.  :(


Wouldn't that senario show up as a High Resistance fault?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: asbokid on January 23, 2012, 08:22:21 PM
Playing Devil's Advocate a bit here...

In 2009, Professor Barry Forde of Lancaster University produced a Technical Reference report on LLU (local loop unbundling) for the JANET Network Access Programme. [1]

There is a table on page 7 of Forde's report. It lists the range of wire types used historically in BT's network.  The table shows eight different types of copper cabling and four different types of aluminium cable.

Each type of cable is listed with a loop resistance (measured in ohms/km) and an insertion loss (measured in decibels/km @ 1600Hz).

That table from Forde's report is attached below.

The figures for insertion loss are interesting. They appear to show that heavier gauge aluminium cabling (0.8mm) can outperform lighter gauge copper cabling (0.5mm), in terms of insertion loss at 1600Hz.

However, 1600Hz is at the low-end of the voiceband. It may be unrepresentative of the insertion losses found at the much higher frequencies used in xDSL broadband access systems.

[1] http://www.ja.net/documents/development/llu/llu-technical-document.pdf

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Maturecheese on January 23, 2012, 10:25:17 PM
Is it possible to officially find out if a line is Aluminium and the thickness of it?  If one can and it turns out it is aluminium is there a hope in hell of getting it replaced by either copper of fibre in the next decade?  I suspect the costs involved will rule it out indefinitely.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: asbokid on January 23, 2012, 11:53:30 PM
Is it possible to officially find out if a line is Aluminium and the thickness of it?  If one can and it turns out it is aluminium is there a hope in hell of getting it replaced by either copper of fibre in the next decade?  I suspect the costs involved will rule it out indefinitely.

It would be reassuring to learn that BT Openreach has a database in which it records the cable type(s) and lengths used in every subscriber line.   Though, in practice, the records are probably very vague.  Maybe the use of aluminium conductors in the larger distribution bundles is recorded?

Openreach must have a long-term programme to replace all that aluminium with copper.  Has that programme ever been disclosed?  Copper will be obsolete by the time the aluminium is eventually replaced, especially if Walter has his wicked way with FTTP rollout!

You can bet that the replacement programme would accelerate rapidly if the price of aluminium were to soar and the copper price were to plunge. However, that doesn't seem likely in the near future. Here are the Friday close (cash) prices on the London Metal Exchange for aluminium and copper.  The prices are quoted in US dollars per metric ton.

Aluminum  2184.00
Copper      8230.50

As for discovering whether your own twisted pair has aluminium conductors, without access to Openreach records, it's a good question.  Maybe the line characteristics data obtained from the modem could give a strong indication. It's a difficult problem.  The line could be 'inhomogeneous' along its length, comprising multiple sections of different cable types.  And maybe the succession of cable joints is causing more damage to the signal than the types of cable in use?

cheers, a
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on January 24, 2012, 01:31:21 AM
Quote
EDIT  If the line is Aluminium then I'll just have to put up with slower speeds but it doesn't explain the discrepancies between my line and next doors as surely if mine is aluminium so is hers.

Two adjacent properties with drop-cables from the same pole, which are fed via the same (aluminium) multi-pair D-side cable from the PCP. How can one pair have 10 dB more attenuation than the other? Possibly because of more (defective) joints. Aluminium is an amphoteric metal; it reacts readily with both acids and alkalis. Aluminium is actually a very reactive metal. It appears to be fairly stable and unreactive because of the thin film of aluminium oxide that rapidly forms on its surface. Now get two pieces of aluminium in contact with yet another metal & atmospheric moisture and the aluminium will readily corrode. If it is expected that an electrical signal, at radio frequencies no less, will flow through those two pieces of joined aluminium then there will be a severe degradation of the signal. It will be attenuated. If those two pieces of aluminium are sections of a D-side cable pair and the other metal is an old-style "blue bean" type of crimp, them I'm sure I don't need to type much more.  :(

Wouldn't that senario show up as a High Resistance fault?

Yes, you are correct. A HR fault should be found -- if one (or more) were potentially being investigated.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on January 24, 2012, 12:11:19 PM

Yes, you are correct. A HR fault should be found -- if one (or more) were potentially being investigated.


"if" being the operative word.

In my experience, it has been rather difficult, to say the least, to get anyone from the provider's end to show any real interest whatsoever in potential HR faults, especially when a given connection falls within "acceptable Fault Threshold Rates & is performing above estimated speeds".
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on January 24, 2012, 06:19:56 PM
The HR faults that one can fairly easily get investigated and fixed are those that have an adverse affect on the telephony service. With hisses, crackles, plops, pops, etc, it is a bit difficult for a representative of an ISP / CP to deny the presence of such a fault when the line in question is being used to report the problem. Unless, of course, s/he suffers from a "Nelsonian Ear".  ::)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 05, 2012, 09:54:07 AM
Update 05/02/2012:


Just as an experiment while my sync speeds are still low, at my request, Plusnet have recently experimented with resetting their throughput profile for my connection.

BT's SIN 498 document states that ISPs should try to set throughput profiles to closely match achievable speeds to avoid traffic losses etc.

I was seeing really high error counts (millions at a time), even following the latest engineering work to replace a section of dropwire, that did actually help to further stabilise my connection.

I was on a 37Mb Plusnet profile, which means full speed throughput for the currently capped 40Mb offering.

As my speeds have not exceeded 30Mb since July, I asked Plusnet to lower my throughput profile to 32Mb.
Error counts have reduced dramatically & likewise the frequent "on the fly" re-syncs, usually at lower speeds, have also reduced.

My sync speeds have been gradually increasing & I actually achieved just over 30Mb sync speed a few days ago (for the first time since July!).

Hoping, that lower error counts & less frequent re-syncs would be seen by DLM as a more stable connection, I was hoping for a prolonged error-free connection up time.

Everything was looking positive until I arrived home from work on Thursday, when I spotted an engineer at the top of the pole nearest to my house.

Of course, I rushed inside just to check everthing was still O.K. with my connection.
It wasn't.
I could see that for around 1/2 hour my SNRM had been all over the place & there was evidence of a few re-syncs in quick succession.

I spoke with the engineer & he denied touching my connection as he was working to provide a new one for someone else.
I ended up with a sync speed of not much above 20Mb.

as it was dark by the time the engineer left, my subsequent re-sync was O.K. speed-wise, but below 30Mb again.

Anyway, I contacted Plusnet just to let them know what had been causing this recent instability.

When I retuned from work on Friday, everything seemed fine again, until I noticed my connection re-syncing again.
Oh no. I thought. That enginer has messed up my connection again.
Just as a check, I looked out of the window & there was a different engineer at the top of the same pole.
He also denied touching my connection, but I lost a few more Mb in sync speeds again.

I rebooted the modem yesterday morning & achieved just below 30Mb sync speed.

I have reported both these incidents to Plusnet & requested an engineer's visit to thoroughly test my whole D-side using TDR and/or whatever else would be necessary & if no "issues" are detected, to INSIST on BT resetting my connection to 40Mb as it has never actually been confirmed that it has been reset to 40Mb following ANY of the previous engineers' visits.

So the message is that ISPs attempting to send too high a throughput on a poorly performing connection can actually cause even more instability & actually lower ongoing sync speeds.

Watch this space for any updates.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 05, 2012, 12:24:46 PM
Hi Paul,

Your continuing saga does strongly suggest there are difficulties in the supply-side of your D side connections back to the PCP.
Why else would it be necessary for TWO engineer visits just to provide a new service to somebody else?
(Yet more inefficient and costly deployments of BT engineers.)

For those who are yet to become embroiled in the ever increasing impediments of the ageing 20 CN infrastructure,

(That means EVERYBODY until such time as the nation wakes up to the crucial requirement¥¥ of point-to-point Fibre To The Home.)

it is probably worth explaining how most distribution arrangements are organised.

There will usually be several D side cables radiating from every PCP green cabinet.
Each cable usually takes the minimum TOTAL cable length strategy "hedgehopping" back and forth to each Distribution Point (DP); thus often increasing the D side lengths to each house.
At every DP (and sometimes at intermediate points if a cable has been damaged and repaired) a cable joint is inserted with every wire of every active pair individually crimped in its "birds-nest".
Some pairs will be straight-through connections to the next joint. The remaining local pairs depart from the main cable in a multicore (e.g. 20 pair) cable to the actual distribution box nearly always at the top of the pole**.
I hope those who have not yet been lost in this labyrinth will observe that their service is connected by (Petroleum) jelly crimps at every joint up to the DP and then there are two sets of connections leading to the drop cable to the house, sometimes with yet more connections there.

Every crimp is a potential source of a high resistance connection, particularly with age-brittle aluminium alloy for EVERY crimp in the entire joint.

Perhaps it is now obvious what a stirling job the average BT linesman does and the thankless, frustrating, task that awaits him or her when attempting to find a faulty joint.
Their JDSU (or similar) test equipment can help indicate the approximate distance of the discontinuity, but it is a very time-consuming task to be completed under significant pressure to get on to the next job.

Does anybody now wonder why so many, sometimes intermittent, faults go undetected and un-repaired for so long ?

** The above description covers what I believe to be the majority of phone connections. There are three exceptions that I'm aware of:-

1. The distribution on more modern estates where all cables are underground. In this case the same joints are made back to the PCP but the local DP function is done within a single joint sleeve.

2.  There are some hollow metal distribution columns where the DP is situated at ground level within the base of the column.

3.  Similar distribution arrangements but using cables and boxes fixed directly to buildings.

¥¥ Apologies if have already rambled off-topic for too long here so I will start a new topic for a practical solution to this horrible quandary which is here:-

http://forum.kitz.co.uk/index.php/topic,10655.msg210353.html#msg210353

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 05, 2012, 05:39:43 PM
Everything was looking positive until I arrived home from work on Thursday, when I spotted an engineer at the top of the pole nearest to my house.

Of course, I rushed inside just to check everthing was still O.K. with my connection.
It wasn't.
I could see that for around 1/2 hour my SNRM had been all over the place & there was evidence of a few re-syncs in quick succession.

I spoke with the engineer & he denied touching my connection as he was working to provide a new one for someone else.
I ended up with a sync speed of not much above 20Mb.

. . .

When I retuned from work on Friday, everything seemed fine again, until I noticed my connection re-syncing again.
Oh no. I thought. That enginer has messed up my connection again.
Just as a check, I looked out of the window & there was a different engineer at the top of the same pole.
He also denied touching my connection, but I lost a few more Mb in sync speeds again.

To me that is the evidence of a defective DP, which needs to be rectified by Openreach.  :(  A total "refit" of the pole should be implemented.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 06, 2012, 09:00:55 AM
@ BKK,

Although that might well seem to be the most obvious component (culprit ?), there are probably others.
I very much doubt if BT Openreach would even consider any cause postulated by their clients, especially as there won't be any official cross reference between Paul's service and the new service(s).

Perhaps the most that could be asked for is sight of the TDR data from the JDSU. That also assumes that PlusNet have the capability to obtain action from BT Openreach.

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 06, 2012, 01:18:08 PM
Indeed, Walter. My comment was based on pure logic rather than that of the fantasy world in which the Evil Empire of Newgate Street likes to reside.

Perhaps Mr Eagle could rent a JDSU HST-3000c for one weekend and obtain his own TDR data for the line?  :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 06, 2012, 05:20:38 PM
Indeed, Walter. My comment was based on pure logic rather than that of the fantasy world in which the Evil Empire of Newgate Street likes to reside.

Perhaps Mr Eagle could rent a JDSU HST-3000c for one weekend and obtain his own TDR data for the line?  :-\

Indeed, that is one option.

Another would be to purchase a used 301c 'Mole', or a Hawk tester (at a reasonable price).
They may be uncalibrated, but would surely indicate any potential "issues".

If any such tests proved inconclusive or completely clear, the question would remain - how on earth did I ever achieve a reasonably sustained throughput of up to 33Mb, with a probable sync speed of around 35Mb or higher, for the first month (on the "slower" 8c profile) & why can I not achieve or improve on it now that I am on the "faster" 17a profile, after so many engineer visits that have supposedly "fixed" everything at each visit?

EDIT:
Examining my Hlog graph (plotted as lines as apparently plotted via a JDSU, rather than the usual boxes) does not indicate any particular HR or capacitance issues for the tones my connection is actually able to use (see attached) other than generally highish attenuation over frequency.

Could it be simply a matter of crosstalk due to increased takeup of FTTC services from my cabinet or that output power from my cabinet has been reduced to avoid crosstalk onto ADSL frequencies?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 06, 2012, 10:44:00 PM
EDIT:
Examining my Hlog graph (plotted as lines as apparently plotted via a JDSU, rather than the usual boxes) does not indicate any particular HR or capacitance issues for the tones my connection is actually able to use (see attached) other than generally highish attenuation over frequency.

Could it be simply a matter of crosstalk due to increased takeup of FTTC services from my cabinet or that output power from my cabinet has been reduced to avoid crosstalk onto ADSL frequencies?


If everything else proves to be satisfactory, then either of your postulations could be the answer. However I am highly suspicious of what you have recently reported -- that when a "proper man" goes up the pole, your service throws a "funny fit".  :-\

Also, you are no closer to finding the length of your D-side cable.  :-X
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 06, 2012, 11:19:39 PM
If everything else proves to be satisfactory, then either of your postulations could be the answer.

I doubt it really. I was just trying to remain "positive"

Quote
However I am highly suspicious of what you have recently reported -- that when a "proper man" goes up the pole, your service throws a "funny fit".  :-\

Me too. It threw another funny fit just after 9:00 tonight. Sync speed back down to 23753 K & SNRM levels/attainable rates all over the place.
No massive error counts though.

Quote
Also, you are no closer to finding the length of your D-side cable.  :-X

True. I wonder if we should start a sweep for the real distance.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 07, 2012, 10:17:28 PM

Me too. It threw another funny fit just after 9:00 tonight. Sync speed back down to 23753 K & SNRM levels/attainable rates all over the place.
No massive error counts though.


I rebooted the modem at 14:49 today, following advice from Plusnet:-

"I would recommend to force a re-sync to obtain a higher sync speed and then attempt to maintain this connection for as long as possible."



Not bad - Sync speed 30160 k & SNRM at 6.4dB (actually the highest sync speed since last July).
(http://speedtest.net/result/1757889701.png)


It was a bit short-lived though.
A grand total of 2 hours & 12 minutes later, at 17:01, the connection re-synced itself.

I didn't spot any engineers up the pole this time though.
Maybe they don't need to come back & mess up my connection any further as they seem to have done a prettty good job of it already  :o >:(


Sync speed ended up back down to 23367 k, with SNRM back up to 10dB:-
(http://speedtest.net/result/1758242447.png)

Of course, I immediately reported this to Plusnet, reminding them that my line was quite stable & gradually building speed until 2 engineer's messed it up for me late last week.

Hopefully they will confirm what they will be doing about it some time during tomorrow.

I'm sure I posted a similar message earlier on.
I wonder if it was removed because I may just have let a naughty word slip in.
It did display as "{censored}" though.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 08, 2012, 12:04:50 AM
@ paul,

I suspect you have long since passed the record for the longest thread on Kitz's famous site - and VERY well done for being so persistent !

(In a different context perhaps you have noticed my tenacity elsewhere !)

I did just have a nasty fear that the engineers' up the pole might have been using a tone generator but I'm relieved  to read your recent reports of ongoing difficulties.

I'm trying to summarise the likely causes of the recent disturbances after quite a long time of reasonably steady, but degraded, performance.

1. It is much colder now that when you started this marathon, but there were perturbations in warmer times too, so this is unlikely to be a major factor.

2. Upon the assumption that the engineers are actually climbing on the pole, physical movement and vibration on the pole generally might be a contributory factor.
I.e. a)  it is possible that a joint or the local feed cable has poor crimps and / or corrosion
      b)  the drop wire itself or the cable towards the static house components is damaged; however I seem to recall that the drop wire has been replaced ?
      c)  EITHER the idc connections, if they are provided, that your service uses have been stretched or corroded OR similarly the crimp joints, if they are provided, are faulty ?
      d)  assuming that the drop wire was replaced, then the supply cable pair within the DP has been damaged - either the wires themselves or the insulation to other metallic parts is damaged
      f)  an unusual connection method has been employed where there are other components in circuit such as another cable join, perhaps in a BT 66 box or similar ?

3.  Given the current minimal maintenance regime employed by BT Openreach (at least around here), the chances of having the entire DP replaced are probably minimal. You just might, if you are very lucky, persuade the next engineer called out to investigate to swap the pair from the through joint up on to a different pair of connectors and also perhaps to replace the drop-wire with a new length of drop-wire 12 preferably as a single length direct into your NTE.

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 08, 2012, 12:57:41 AM
Walter,

My recollection is that the NTE5/A (in the office at "The Aerie") and entire length of drop-cable from it to the DP pole-top was replaced, with new, a couple of months ago. The reason why that has remained in my mind is because the drop-cable is affixed to Doris' house, Mr Eagle's neighbour to the west, and then travels down the side & along the back of the buildings to it's destination in the office.

My suspicion is thus directed to the pole-top and the junctions "up there" or to the supply cable (20-pair ?) that "climbs" the pole from underground. Perhaps Mr Eagle could take a series of photographs for us to examine? Looking at images from Google maps, dated November 2009, offers no great help.  :no:

Edit: Re-visiting those images, It now looks as if both Doris' and Mr Eagle's drop-cables have a pole of their own, which is fed, in turn, by an aerial feed from a pole on the north side of the road. It is the second pole (on the north side of the road) which has a "climbing" 20-pair and that can be traced back to its "three-cover" joint-chamber, in the east, by the "scar" in the pavement surface. However, it all looks a bit "odd", for I think I can see a "two-cover" joint-chamber in the pavement at the front of Doris' house.  :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 08, 2012, 08:29:42 AM
@ BKK,

I am pleased that you too recall the drop wire replacement.

Following our recent postulation that the latest interventions by BT Openreach engineers to provide a new service somewhere from the existing DP pole, I think we both agree with your para 2 statements upon the likely area of the problem which, if I recall, is across the main road. (It might help if Mr Eagle can confirm whether or not the adjacent houses share a single drop cable as that would imply a break in the drop cable where the two house separate their services. However as that is reasonably remote from DP pole mechanical vibration it seems unlikely that is the culprit.)

We must also not completely rule out other causes of the difficulties at least up to and including the PCP and FTTC.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 08, 2012, 08:39:56 AM
Hi Walter,

I suspect you have long since passed the record for the longest thread on Kitz's famous site - and VERY well done for being so persistent !

(In a different context perhaps you have noticed my tenacity elsewhere !)

I have indeed noticed & I wish you all the best of luck in what appears to be an increasingly uphill struggle.

Quote
I did just have a nasty fear that the engineers' up the pole might have been using a tone generator but I'm relieved  to read your recent reports of ongoing difficulties.

I'm not quite sure what you mean by that. Could you please clarify it for me?

Quote
I'm trying to summarise the likely causes of the recent disturbances after quite a long time of reasonably steady, but degraded, performance.

1. It is much colder now that when you started this marathon, but there were perturbations in warmer times too, so this is unlikely to be a major factor.

A few slight improvements do appear to have occured as the weather has become colder. Some slight improvement did coincide with with being switched to the 17a profile in October (a few more DS bit-loading tones available at the lower frequencies - although the slight speed increase did appear to be the start of me seeing massive error counts).

I have wondered if any contraction of cables could cause a "tightening" effect & make some dry joints better?
Also, I'm sure I have read of a seasonal phenomenon where broadband speeds & stability can increase due to reduced radio propagation/skip in winter, thus reducing any effect of interference/noise levels.

The worst period of instability was from reinstatement of my services at the end of July to around the middle of September.
The double jumpering issue was “fixed” near the end of August.

Quote
2. Upon the assumption that the engineers are actually climbing on the pole, physical movement and vibration on the pole generally might be a contributory factor.

The 2 engineers from last week did indeed climb the pole.
AFAIK, any previous engineers have used a cherry picker.

Quote
I.e. a)  it is possible that a joint or the local feed cable has poor crimps and / or corrosion
      b)  the drop wire itself or the cable towards the static house components is damaged; however I seem to recall that the drop wire has been replaced ?

The drop wire was indeed replaced, along with the complete master socket and faceplate.

Quote
 
      c)  EITHER the idc connections, if they are provided, that your service uses have been stretched or corroded OR similarly the crimp joints, if they are provided, are faulty ?
      d)  assuming that the drop wire was replaced, then the supply cable pair within the DP has been damaged - either the wires themselves or the insulation to other metallic parts is damaged
      f)  an unusual connection method has been employed where there are other components in circuit such as another cable join, perhaps in a BT 66 box or similar ?

The pole is an old timber telegraph pole.
The new drop wire does appear to be quite tight in comparison with the previous sagging drop wire.
My immediate neighbour & I do not have BT 66 boxes.

Quote
3.  Given the current minimal maintenance regime employed by BT Openreach (at least around here), the chances of having the entire DP replaced are probably minimal. You just might, if you are very lucky, persuade the next engineer called out to investigate to swap the pair from the through joint up on to a different pair of connectors and also perhaps to replace the drop-wire with a new length of drop-wire 12 preferably as a single length direct into your NTE.

I think the chances of any of that are remarkably slim.


The whole point of all this is that my connection was perfectly fine until it was accidentally disconnected at the end of July & that nobody has yet discovered why it has been rather unstable with low speeds ever since.

For all I know, the double jumpering could well have been in place right from the start, the drop wire could have needed replacing right from the start, the internal shielded cable that has raised a few eyebrows was in place right from the start.

All of these various “fixes” have brought some slight improvement, but the underlying cause of the issue, in my opinion, is still to be located & “fixed”.

If all the other incidental “fixes” have improved matters, maybe I should by now be expecting the full 40Mb sync speed, very low error counts & very infrequent re-syncs.

Maybe I should also be looking forward to a slight possibility of being able to achieve something from BT’s soon to be rolled out 80/20 speed doubling.

My maximum attainable rates are still only around 35Mb maximum & that is only immediately following a re-sync (on the occasions that I do actually sync at just below 30Mb).

My connection MUST have actually synced at around 35Mb or so when I was able to achieve throughput of 33Mb (as reported via speedtest.net & mybroadbandspeed.co.uk et al.

Even then, I was aware that BT’s own speed/performance test produced DS throughput speeds of 1Mb to 2Mb lower than the other online testers.

Here is just one example of the result from a BT speed test, from around 23:00 on 30th June, some 6 days after installation.
Download speed achieved during the test was - 32359 Kbps.

According to BT’s SIN 498 document, the “training period” for FTTC services is not 10 days (it would be quite helpful if all ISP agents were aware of that).
The document states that if any severe instability is seen within the first 24 hours of installation, DLM will take immediate action.
Otherwise, it will take action within the next 24 hour period.

As we know, my connection was able to maintain higher speeds & apparent stability right through the irrelevant 10 day period starting 24th June to 21st July when it all suddenly fell apart.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 08, 2012, 09:29:38 AM
Hi b*cat,

Walter,

My recollection is that the NTE5/A (in the office at "The Aerie") and entire length of drop-cable from it to the DP pole-top was replaced, with new, a couple of months ago. The reason why that has remained in my mind is because the drop-cable is affixed to Doris' house, Mr Eagle's neighbour to the west, and then travels down the side & along the back of the buildings to it's destination in the office.

My suspicion is thus directed to the pole-top and the junctions "up there" or to the supply cable (20-pair ?) that "climbs" the pole from underground. Perhaps Mr Eagle could take a series of photographs for us to examine? Looking at images from Google maps, dated November 2009, offers no great help.  :no:

I will take some photographs & post them here.

Quote
Edit: Re-visiting those images, It now looks as if both Doris' and Mr Eagle's drop-cables have a pole of their own, which is fed, in turn, by an aerial feed from a pole on the north side of the road. It is the second pole (on the north side of the road) which has a "climbing" 20-pair and that can be traced back to its "three-cover" joint-chamber, in the east, by the "scar" in the pavement surface. However, it all looks a bit "odd", for I think I can see a "two-cover" joint-chamber in the pavement at the front of Doris' house.  :-\

The "two cover" joint chamber is a red herring.
It has NTL on it, but I have no idea what it is as it has been confirmed there is absolutely no possibility of me having NTL/Virgin cable TV or broadband.

Please see the attached roughly drawn sketch of the poles & cables.

From the PCP, the supply could take one of two routes Route A, up the main road or Route B up a smaller road.
Quite thick looking cables all meet at the pole at the road junction.
One engineer thought it came via the shorter route & another thought it came via the longer route.

The dotted cable line may be an underground supply from the pole in front of the petrol station to the pole across the road from my house.
Alternatively, again thick cables can be seen going up the lane behind the petrol station & down the footpath to the pole facing my house.
None of the engineers have confirmed which route is used.

Regardless of which routes are actually used. The line length still appears to be less than the 1000m as displayed on an engineer's JDSU.

For all I know, my connection might have been originally supplied via the more direct underground route (shown dotted - if it actually exists).
How could I tell whether it exists or not?

When my services suddenly ceased for 4 days back in July, it might have been an expensive to repair issue in the underground section.
So my connection might have been rerouted around the back of the petrol station & down the footpath, adding quite a few metres to the overall D-side length.

I have asked the question a few times, but unfortunately nobody can (or they just won't) confirm the exact route for me.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 08, 2012, 07:31:56 PM
Hi Paul,

Quote
I'm not quite sure what you mean by that. Could you please clarify it for me?

BT Engineers regularly use tone generators and tone tracers to identify the required pairs to be connected or changed etc.
I had wondered if their tone generators had produced cross talk on to your rather delicate CCT.
The fact that the problems continued after the BT engineers had gone away suggests tone generators are unlikely to be the cause of all your anguish.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 26, 2012, 08:53:13 PM
Just for "fun" I thought I would plot my IP Profiles since FTTC was installed 24th June 2011.

The graph is attached.

I had to calculate my IP Profile from my Sync speed & speed tests for a few of the days, as I wasn't logging my IP Profie all the time (FTTC's IP Profile works out at 96.8% of sync speed (approx) & speed tests approximate 97% of IP Profile (at quiet times).

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 27, 2012, 12:58:12 AM
Hmm.  :hmm:  Not a pretty sight.  :no:

What you really need is for B*Sheep to be seconded from his normal Lancashire & Cumbria area to the Devil Worshippers' catchment area and then to be assigned to resolve all of your long standing line issues . . .  :-X
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 27, 2012, 08:22:36 AM
@ Paul,

You could perhaps illustrate the serious problems of the FTTC implementation by drawing a horizontal line at 15,000 Kbps to show that, as from about 10 November 2011, your line has stayed within the BT Openreach declared acceptable performance levels thus absolving them from all fault-finding responsibilities whatever, whilst you continue to pay for your monthly "sack of potatoes" with varying sized holes in it.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 27, 2012, 12:11:57 PM
Haha,

Nicely worded Walter.

You have to laugh though, otherwise......................

Let's see what happens when BT engineers connect up an extra bit of black underground cabling that has recently been coiled up, ready for connection at the DP at the top of the pole where my drop wire starts.

I have no idea what the cable is for, but it is around 12mm in diameter & it appears to come from a joint chamber a little further away from the cabinet than the pole (maybe 30m or so).


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on February 27, 2012, 12:49:49 PM
Haha,

Nicely worded Walter.

You have to laugh though, otherwise......................

Let's see what happens when BT engineers connect up an extra bit of black underground cabling that has recently been coiled up, ready for connection at the DP at the top of the pole where my drop wire starts.

I have no idea what the cable is for, but it is around 12mm in diameter & it appears to come from a joint chamber a little further away from the cabinet than the pole (maybe 30m or so).


Paul.

There's a couple of reasons that new cable is there Paul.

1) The original 'feed' cable has been diagnosed as faulty in length, and needs replacing. (God, I hope it's that and your issue gets resolved).

2) The DP needs 'Relief' ( Plenty of 'Carry-on' puns allowed at this point), whereby there aren't enough 'pairs' at the DP for the ammount of EU's demand. This will mean another 'DP Block' will be mounted on the pole. Have any new properties gone up that could be 'fed' from this DP ?? That would usually indicate that 'DP elief' is in progress. 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 27, 2012, 06:10:23 PM
Update 27/02/12:

Well, On arriving home I noticed the cable had been connected whilst I was at work this afternoon.

In my hope/excitement that maybe a new feed cable had been installed, I rushed inside to check my connection's stats.

Imagine my dismay when I saw that sync speeds were only 19932 kbps DS & 5818 kbps US.

I checked my logs & saw that there had been 4 re-syncs between 15:11 & 15:29 this afternoon (at varying lower speeds than of late).

Thinking that DLM may have been a bit confused by these re-syncs in quick succession, believing there was a general connection problem, I rebooted the modem at 17:05.

The result was rather disappointing sync speeds of 20126 kbps DS & 5844 kbps US.
SNRM was 6.2dB DS & 6.0dB US.

A short while later, I noticed that SNRM had suddenly shot up to 11.8dB DS & 6.2dB US.

That looked promising (plenty of spare DS margin), so I rebooted the modem again.

The result was 26590 kbps DS & 5877 kbps US with SNRM of 6.3dB DS & 6.1dB US.

1 Hour later SNRM is fluctuating up & down a little, currently at 5.4dB, but as evening is now drawing in a drop is expected.

Attenuation levels are more or less unchanged.


I will see how it all pans out over the next few days, but all-in-all, it doesn't look too promising at the moment  :(

(http://www.speedtest.net/result/1800347678.png)


I know that Alex from Plusnet looks in on this thread from time to time, so I won't mither him too much again (not just yet anyway)  ;)


@ Black Sheep:-

Wouldn't the above qualify as "engineering works" that may now require a BT sync/profile reset back to 40Mb, just to see what DLM will make of it?

There are no new properties in the area that could be fed from this DP, but it may be possible that some dwellings have been split into flats, or just require additional lines.


Paul.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 27, 2012, 06:47:54 PM
@ Paul,

Does the new cable replace the existing one into the same DP box or even into a new one?
If so that would explain some drops as your pair would need to be re-connected both in the u/g joint and at the DP.
If not, then there should not have been any disturbance of your connection unless (unlikely) your feed cable or DP are badly damaged and any movement disturbs everything.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 27, 2012, 06:59:09 PM
Hi Walter,

I can't say at the moment.
I'll try to have a look in the daylight tomorrow.


My connection does appear to be easily disturbed though.
Do you recall a couple of weeks ago that I mentioned 2 separate engineers causing re-syncs at lower speeds & both denying they had touched my connection?


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 27, 2012, 08:53:44 PM
Just a comment. If possible, power down and disconnect the HG612 modem from the line for as long as you can leave it.

That will allow the DSLAM line-card's port "plenty of time" to do "whatever it fancies" with the line, without having an active CPE providing any loading / termination. I would aim for 24 hours but if that is too long, try 12 hours.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 28, 2012, 06:15:05 AM
@ b*cat,

That might be worth a shot.

I might try it at weekend as I really need the internet during the week to access the office servers from home.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 28, 2012, 10:04:41 PM
@ Walter,



Does the new cable replace the existing one into the same DP box or even into a new one?
If so that would explain some drops as your pair would need to be re-connected both in the u/g joint and at the DP.
If not, then there should not have been any disturbance of your connection unless (unlikely) your feed cable or DP are badly damaged and any movement disturbs everything.


Well, while I was peering up at the various boxes at the top of the pole this morning, more or less confirming that my drop wire is still connected to the original quite old looking cable & that the new cable feeds someone else's connection an engineer arrived carrying his ladders.

I told him what had been going on & he said that none of it should have affected my own connection.
He may well have been/probably was the same engineer from yesterday.

He did say he would have a look for any dodgy connections & after I suggested he may wish to check my connection with a TDR meter after he had completed his work, just to make sure everything was still O.K. I left him to it.

I have to congratulate him for his efforts as when I returned a few hours later, my sync speed had gone down to 18884 kbps!

(http://speedtest.net/result/1801900350.png)

Seeing that SNRM was a shade over 15dB, I rebooted the modem just before 2:00 pm, achieving a sync speed of 27400 kbps, with SNRM of 7.8dB.

(http://speedtest.net/result/1801938138.png)

The connection had also re-synced at 22:15 last night at 26574 kbps, just a few kbps down from the 26590 kbs from yesterday afternoon.

The connection re-synced itself again at 19:23 this evening at 23670 kbps, SNRM at 9.9dB.
A sudden burst of over 100,000 CRC/RSUnCorr errors in the preceding minute may have been the trigger, along with SNRM dropping the minute earlier.

(http://speedtest.net/result/1802932228.png)


To say I am getting thoroughly fed up with all this is now rather an understatement.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on February 28, 2012, 10:26:13 PM
Hi Paul,

Poor you - what a chapter of difficulties !

However there is at least an opportunity now to get your service transferred to the new cable.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 29, 2012, 07:57:07 PM
Some good news & a slight glimmer of hope............

Plusnet are about to arrange another engineer's visit to check my line, based upon the most recent evidence of my connection's performance.

I won't dust off the invitations for the 33Mb party just yet though.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on February 29, 2012, 08:46:27 PM
I think you should threaten PlusNet with a good pecking, unless they arrange for Black Sheep to be assigned the job . . .  :P
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on February 29, 2012, 09:22:27 PM
I think you should threaten PlusNet with a good pecking, unless they arrange for Black Sheep to be assigned the job . . .  :P

If only...........................

BS would certainly have a massive head start as he has already seen & contributed to the extensive case notes.

Altogether now............"He achieved 33Mb actual download speeds during the first month"
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 01, 2012, 07:32:23 AM
Ha ha ha ..... thanks for the vote of confidence lads. There has to be somebody capable of peforming full tests on BE's patch !!  ???
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 01, 2012, 07:37:02 AM
Ha ha ha ..... thanks for the vote of confidence lads. There has to be somebody capable of peforming full tests on BE's patch !!  ???

There is, but he must always be on leave when it is my turn  :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 01, 2012, 12:38:34 PM
It may be a deliberate ploy to go on Annual Leave, when your job starts to crop up on our systems, BE. He he he ..... :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 01, 2012, 05:42:36 PM
Quick update Folks:-

Feedback from Plusnet

"An appointment has been booked for:
03/03/12 between 08:00 and 13:00."

Then:-

"we have received an update from Openreach diagnostics stating "Dropping connection and errors recorded in history. Passed to field eng to investigate."  Because an engineer has already been assigned it may cause the appointment for 03/03/12 AM to fail to book correctly."

&:-

"All I can say is that the errors and retraining must be fairly high as BT have booked an engineer to go out and look at your line without any consultation with us.  This usually only happens when line testers locate a definite issue on your line.  Let's see what the engineer notes state before reading in to that too much."


It all looks rather promising, but I won't build my hopes too high just yet  :-\

I can just imagine the queue in the Oldham exchange, of all the engineers trying to book some leave, starting 3rd March  :D

Some poor soul will end up drawing the short straw.

They may even need to call in an engineer who has read the case notes from another patch  ???
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 01, 2012, 05:59:10 PM
Quote
I can just imagine the queue in the Oldham exchange, of all the engineers trying to book some leave, starting 3rd March  :D

I like the BT code for your exchange -- MROLD. It allows one to picture all sorts of situations involving a Mr Old. Who could that be?  :P

Quote
Some poor soul will end up drawing the short straw.

They may even need to call in an engineer who has read the case notes from another patch  ???

As long as he is wearing a black wool coat it may be to your advantage. (Just don't mention the mint sauce!)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 01, 2012, 06:06:00 PM

I like the BT code for your exchange -- MROLD. It allows one to picture all sorts of situations involving a Mr Old. Who could that be?  :P


Something else you can't remeber at your ripe age?

Quote
As long as he is wearing a black wool coat it may be to your advantage. (Just don't mention the mint sauce!)

Hmmm, sounds like a "tasty" proposition.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 01, 2012, 06:07:41 PM
Quote
I can just imagine the queue in the Oldham exchange, of all the engineers trying to book some leave, starting 3rd March  :D

I like the BT code for your exchange -- MROLD. It allows one to picture all sorts of situations involving a Mr Old. Who could that be?  :P

Quote
Some poor soul will end up drawing the short straw.

They may even need to call in an engineer who has read the case notes from another patch  ???

As long as he is wearing a black wool coat it may be to your advantage. (Just don't mention the mint sauce!)

LOL ..... mint sauce. ;D

Am chuffed for you BE. I must be being thick here, but am not sure how Openreach can view your DSL history, as you are on LLU ??? I wasn't aware 'we' could view your logged events ?? Is it not Plusnet who have looked at your recent poor history, and Openreach have agreed to take the case off them without debate ??

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 01, 2012, 06:09:48 PM
Hmmmm, reading it again, it might be that we haven't viewed your DSL history, but having performed an initial 'line test' of the MPF, conditions have shown up that would warrant a visit.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 01, 2012, 06:28:32 PM
I THINK it is something to do with a new tool that reports Error Seconds & Serious Error Seconds, disconnections etc.

I'm sure I read about it somewhere on the Openreach site, but I can't locate the relevant briefing at the moment.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 01, 2012, 07:37:15 PM
I THINK it is something to do with a new tool that reports Error Seconds & Serious Error Seconds, disconnections etc.

I'm sure I read about it somewhere on the Openreach site, but I can't locate the relevant briefing at the moment.

The only 'tool' we use to monitor DSL is 'WHOOSH'. This monitors ES,SES and UAS. The latter being 'Unavailable seconds', or, a disconnection to you and me.

It's not a new tool really, it's always been available to BT Wholesale (and we engineers actually, in the early days of Broadband), it's only "New" to Openreach in that they've given us access back after much protestation from the likes of myself.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 04, 2012, 09:25:20 PM
Update 04/03/2012:

Well, the engineer didn't actually arrive yesterday, probably as BT are also also doing their own initiated tests as "they" had supposedly noticed frequent disconnections & high error counts.

I have yet to receive any feedback as to when/if an engineer will visit.
However, as my current sync speed is so low (23670k), error counts are currently also quite low.

Alex from Plusnet has confirmed that any investigation initiated by them will indeed to be to try to determine why my connection has been unable to exceed 30Mb sync speed since July.
My speed estimate at that time was only 14.6Mb, so it was difficult to claim a fault.
However, it has been estimated at 30Mb for a couple of months now.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 09, 2012, 09:34:38 AM
Update 09/03/2012:

Well, after yesterday's rearranged appointment being rearranged again for this morning, the engineer, ANDY, has just left.

He has left me in a bit of a state really.

Andy has visited previously, but neither of us could remember what he did last time (or was instructed by BT not to do).

My sync speed (following a BT reset, requested by Andy) has ended up at 35322k & these are throughput speeds:-

(http://speedtest.net/result/1822795493.png)

It is obviously early days yet & errors are starting to clock up (not too quickly yet), but today's visit seems to have finally done the trick after waiting for more than 7 months.

To say I am a reasonably happy chappy at the moment is a slight understatement.

A BIG thank you goes to Andy for listening to me & looking at my evidence.

The IP Profiles graph covering the last 7 months or so seemed to be the "clincher" that made him request the BT reset.

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: camallison on March 09, 2012, 10:25:47 AM
Apart from the reset, did he do anything else this time?

Colin
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on March 09, 2012, 11:58:02 AM
Hi Paul,

That seems a fantastic result - very well done everybody involved !!

However early days as you say = the training period has started again.

Fingers & everything else crossed !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 09, 2012, 03:17:56 PM
Congratulations. Paws crossed, etc.

I suspect that Mrs Eagle will be overjoyed that you will finally be able to find time for her "little jobs" (a new kitchen, a new utility room), rather than playing with 'puters and "things" in your office.  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 09, 2012, 05:12:39 PM
Hi Colin,

Apart from the reset, did he do anything else this time?

Colin

Other than a Pair Quality Test that returned a result of 61, no.

@ Black Sheep - Does that look about "right"?

I tried my hardest to get him to run a "reassurance" TDR test, but he wouldn't do so as my new sync speed already exceeded the newish 30 Mb estimate (It was only 14.6Mb a few months ago).

This was his update to Plusnet on completion of this morning's visit:-

"SFI notes: cse called for co-op on ongoing speed issue , circuit in sync at 27.4meg down. rrt shows geren since 28/02/2012. I have recalculation dlm as suspect may have failed to increment automatically.

now in sync at Downstream Line Rate (Mbit/s) 35.3 Upstream Line Rate (Mbit/s) 6.4 these speeds are well
above that expected for area given distance from pcp and local lineplant."   

As long as the connection stays in sync over the next few days & error counts don't cause DLM to take "negative" action, I will remain reasonably pleased with the eventual outcome, ignoring the thought that the switch to the 17a profile could/should have brought my connection a little closer to a stable 40Mb sync speed.


Paul.

EDIT:

IP Profiles graph following this morning's visit is attached.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 09, 2012, 05:34:35 PM

That seems a fantastic result - very well done everybody involved !!

However early days as you say = the training period has started again.

Fingers & everything else crossed !

I will definitely second Walter's sentiment & thank you everyone for the various snippets of advice that have EVENTUALLY got me back to where I started some 7 months or so ago.

I would like to record my special thanks to Alex R at Plusnet for not simply fobbing me off with this matter.
I admit I may have badgered him to death at times, but he has always been willing to take my comments on board & has been wiiling to look at all the "unofficially obtained" stats that I have provided over the last few months.

It HAS taken a long time & HAS needed a little persistence from me & without access to the stats from an unlocked modem (thanks asbokid) & development of the graphing scripts (thanks b*cat) I would still be stuck with a very unstable & low speed connection.

I will obviously monitor my connection over the next few days/weeks/months, the next 24 hours possibly being the most critical as that is when DLM most likely takes any action it sees fit for FTTC connections.


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 09, 2012, 05:36:38 PM
Cheers b*cat,

Congratulations. Paws crossed, etc.

I suspect that Mrs Eagle will be overjoyed that you will finally be able to find time for her "little jobs" (a new kitchen, a new utility room), rather than playing with 'puters and "things" in your office.  ;)

I imagine that will be the first thing she mentions when I tell her this morning's vist appears to have been a success  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 09, 2012, 05:39:17 PM
Hot off the press folks:-


Update a couple of minutes ago from Alex R at Plusnet:-

"That all sounds very promising indeed.  Like you say it will require monitoring over the course of a few days.  I actually tried to modify your circuit today to 80/20 but unfortunately the option is not available at the moment.  Any issues, just update the ticket."


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 09, 2012, 07:09:47 PM
Hi Colin,

Apart from the reset, did he do anything else this time?

Colin

Other than a Pair Quality Test that returned a result of 61, no.

@ Black Sheep - Does that look about "right"?

I tried my hardest to get him to run a "reassurance" TDR test, but he wouldn't do so as my new sync speed already exceeded the newish 30 Mb estimate (It was only 14.6Mb a few months ago).

This was his update to Plusnet on completion of this morning's visit:-

"SFI notes: cse called for co-op on ongoing speed issue , circuit in sync at 27.4meg down. rrt shows geren since 28/02/2012. I have recalculation dlm as suspect may have failed to increment automatically.

now in sync at Downstream Line Rate (Mbit/s) 35.3 Upstream Line Rate (Mbit/s) 6.4 these speeds are well
above that expected for area given distance from pcp and local lineplant."   

As long as the connection stays in sync over the next few days & error counts don't cause DLM to take "negative" action, I will remain reasonably pleased with the eventual outcome, ignoring the thought that the switch to the 17a profile could/should have brought my connection a little closer to a stable 40Mb sync speed.


Paul.

EDIT:

IP Profiles graph following this morning's visit is attached.


<Talks in hushed tones icon> Nice one BE. We've always said that your line would be capable of these speeds, but crikey, it aint half taken some time to arrive here !!  ;D

The figure of 61 you mention. That is the AC Balance figure that really dictates the quality of your line, in relation to resisting 'noise' ingress. After all, if 'we' could eliminate noise completely, we could probably supply 300Mb down Cu/Ali without the need for FTTC/FTTP.
So, to answer your question ............ yes, 61dB is a great value BE.

What I can't get my head around, is why Andy has decided against performing a TDR scan ?? This is the easiest test in the whole, wide world to accomplish. With multiple 'repeat reports' akin to your job, I would have set the TDR trace going and whilst the trace is running, ring your landline number in order to 'load up' the circuit to its max. In it's 'normal state', the TDR trace would be looking back towards the Exchange against the nominal 50Vdc. If there is a 'HR' developing, but is only small, the TDR will probably miss this. By ringing the circuit with the meter connected, the circuit's conditions change to between 90-120Vac, thus giving the TDR trace a far better chance of 'seeing' the HR.

I digress, Andy was the man-on-site, not me. He must have had his reasons, so I can't really comment further on this.

Either way, fingers crossed, you're back to where you want to be. Big up to you for persevering, and Alex for not giving up.  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 09, 2012, 07:11:58 PM
Although I got a little grumpy over PlusNet's inaction in the early days of your troubles, I would now like to publicly congratulate them for "staying with you". By following that path, they have allowed you, us and themselves to learn more about the "unknowns" of a VDSL2 circuit.  :thumbs:

 :drink:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 10, 2012, 10:09:06 AM
Update 10/03/2012:

From my logs I noticed the modem had resynced "on the fly" at just after 5:00 this morning.

Sync speed is down to 33.14Mb, IP Profile at 32.07Mb & throughput at 30.14Mb:-

(http://www.speedtest.net/result/1824844599.png)


It was a little higher until I disconnected/reconnected the router only to force a new PPP session to update BT's IP Profile. It had stuck at yesterday's 34.19Mb:-

(http://speedtest.net/result/1824592820.png)

Maybe I was just unlucky to connect to a slower Plusnet gateway this morning.

I can’t see what might have caused the re-sync other than DLM trying different settings until it finds a suitable balance between speed & stability over the first 48 hours.
The 10 day training period does not exist for VDSL2/FTTC connections (despite what ISPs & BT agents might tell us).

I noticed that Interleaving had been turned off for both DS & US, hence the ping time of only 5ms.

I thought that a little strange though as I still see quite a lot of various errors & error seconds.

Interleaving had always been on at varying depths (up to 1700) for my DS & off for US until yesterday.

Following yesterday’s DLM reset & until this morning’s re-sync, DS interleaving was at a depth of 16 & US at a depth of 8.
Now they are both at a depth of 1 & 1 (off).

Impulse Noise Protection is also currently at 0.00 for US & DS, as is delay.
I don’t ever recall seeing that previously for my connection.


I think during the next 24 hours will be when the connection stabilises (according to BT’s SIN 498 document):-

“2.2.5 Dynamic Line Management

Dynamic Line Management (DLM) is employed in GEA-FTTC. DLM constantly manages lines to maintain a target stability. It does this for as long as the product exists.

At provision, the line is put on wide open profiles, allowing downstream line speeds of up to 40Mbit/s, and upstream line speeds of up to 2Mbit/s or 10Mbit/s depending on the upstream product option selected.

On the first day of operation, DLM will intervene if severe instability is detected.

Otherwise, DLM will wait until the day after provision before intervening, provided that the line has been trained up for at least 15 minutes during the preceding day.

If DLM intervenes it will set a capped profile with a maximum rate and a minimum rate, where the minimum rate is set at approximately half of the maximum rate.

The purpose of the minimum rate is to ensure that the line does not train at a rate which is significantly below the level the line should be able to achieve. If this happened, then the line is likely to remain at a very low rate till a re-train is forced by the user powering off the Active NTE.”



The time frame mentioned is rather vague (in days rather than hours), so maybe BT’s day starts at 5:00am?

My modem re-synced in the early hours (around 20 hours after the DLM reset), when SNRM is at its lowest.
Maybe it would have achieved a higher speed if it had re-synced at around 2:00pm, when SNRM is usually at its highest.

I’ll resist the urge to FORCE any re-syncs for the next few days as I really don’t want DLM to think my connection has become unstable again.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 11, 2012, 09:02:54 PM
Update 11/03/2012:

Well, since the tentative joy following Friday's DLM reset when my connection synced at over 35Mb, there have been a number of connection "on the fly" re-syncs.

The connection has just re-synced at 23887k, resulting in an IP Profile of 23120k & throughput speeds are :-

(http://www.speedtest.net/result/1827877091.png)


Not looking quite so good after all then  :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on March 12, 2012, 12:24:38 AM
@ Bald_Eagle,

I remember you said you were initially quite pleased, as the fibre service remains significantly faster than your old exchange based ADSL solution.
However I'm sorry to say these types of problems are inevitable on some, hopefully a very few, twisted pair lines which are demonstrating their lack of VDSL capabilities for a reliable future-proof solution.
Matters are exacerbated by the lack of a Universal Service Obligation.

In this respect the Virgin Media co-axial solution seems more reliable, although again it must be approaching the network capacity.
Note that it is in effect a "water-pipe type solution" with everyone being fed by a single sealed fat coaxial cable. Their failures will become much more obvious much faster.

Perhaps we all need to become Lunies up in the Vale of Bowland !!!!

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 19, 2012, 07:14:37 PM
Update 19/03/2012:

My connection now appears "quite" stable, sync speed 29822 k, with 36Mb+ attainable over the last few days (connected for almost 183 hours now - a record???)

Being switched to the 80Mb/20Mb trial some time tomorrow (as an experiment on a sub-40Mb connection).

I don't expect any miracles, but watch this space............


Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 20, 2012, 04:56:32 PM
Update 20/03/2012:

It seems that I was switched to the 80/20 Trial just after midnight last night.

It WAS just an experiment & miracles weren't expected, neither were they delivered.

This is the confirmation from Plusnet from this afternoon:-


Code: [Select]
Test Outcome Pass
Test Outcome Code GTC_FTTC_SERVICE_0000
Description GEA service test completed and no fault found .
Main Fault Location OK
Sync Status In Sync
Downstream Speed 32.2 Mbps
Upstream Speed 5.7 Mbps
Appointment Required N
Fault Report Advised N
Profile Name 0.128M-80M Downstream, Interleaving Off - 0.128M-20M Upstream, Interleaving Off
Time Stamp 2012-03-20T00:00:00

PTTR: 27681 (31196 profile on 20/03/12)

RADIUS: 14:24:43 (on going)

Summary:  Line now on the 80M profile with INP Off but will likely change profile shortly
as the line is only achieving 32.2Mbps due to loop loss limitations.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on March 24, 2012, 02:46:59 PM
How has your connection been Paul?

I was put on 80/20 myself as you know, at provision my speeds went to 38/5 up and have settled at 33/5, I noticed it's 2 days before DLM makes changes.

Good luck with your connection mate!

All the best,

Josh
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 25, 2012, 07:46:33 PM
Hi Josh,


How has your connection been Paul?


Not brilliant. See the attached IP Profiles graph.

The 80/20 trial was just an experiment, to see if perhaps power would be increased to try to give me "something" from the highest frequency band.

Unfortunately, it was a non-starter.

The only thing that got my speeds up a little was the DLM reset while I was still on the 40/10 service.

It gave me a 35Mb sync speed & 33 Mb throughput, but it only lasted a few hours before the connection re-synced at a lower speed.

There have been a few re-syncs since then, 4 in quick succession this morning that left me with a sync speed of only 24.9Mb until I rebooted the modem & achieved a sync speed of 29.11Mb. 



Quote

I was put on 80/20 myself as you know, at provision my speeds went to 38/5 up and have settled at 33/5, I noticed it's 2 days before DLM makes changes.



My connection obviously couldn't wait for 2 days  :(

From the other forum, I notice you sometimes have much higher Attainable Rates than that.

Have you tried out the Windows "Ongoing" graphing scripts that MIGHT just show where things look "problematic"?



Quote

Good luck with your connection mate!


I don't think it's luck that I need, rather an engineer to find the "fault" & fix it once & for all.


Paul.


EDIT:
Would you Adam & Eve it?

The connection re-synced again at 8pm.
Sync speed down to only 23.16Mb.

It MAY have coincided with an incoming phone call, but SNRM had gradually dropped to 2.2dB from 6.1dB one hour earlier.

A few minutes following this latest re-sync, SNRM peaked at 10.3dB, but it seems to be fluctuating quite a bit.

The connection also re-synced around 40 minutes later, at 27.1Mb.

It may be coincidence that the weather has been quite warm today?
The modem has remained quite cool though.

The attached graphs show fluctuating SNRM & Sync speeds today.

Testing a telephone with a dangly filter in the test socket (everything else disconnected - apart from the VDSL2 connection in it's usual socket) causes big SNRM drops.


@ Black Sheep

Any suggestions for what to say when I contact Plusnet yet again on Monday?

P.S. The whole master socket & faceplate was completely replaced in November when my drop wire was also replaced.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on March 25, 2012, 11:43:56 PM
@ paul,

I know of one case only, where a brand new SSFP of BT origin failed within 6 weeks.
I know this is clutching at straws but you might just try getting it changed.

Kind regards,
Walter

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 26, 2012, 08:30:24 AM
Well,


The connection re-synnced again at 05:46 this morning at 28.3Mb.

The internal wiring is still disconnected by removal of the faceplate & a telephone is still plugged into the test socket via a dangly filter.

Strangely, use of the telephone was then only showing a drop in SNRM of 0.5dB (from 6.6dB to 6.1dB).

Obviously the outside temperature was a lot cooler at 05:46 this morning.

By 08:30 (sunny & warm again) use of the telephone causes a drop in SNRM of 2.5dB.

I wonder if warmer, drier weather is having some effect, either upon the cabinet's equipment and/or the D-Side cabling/joints, thus highlighting an intermittent HR fault???
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 26, 2012, 04:05:13 PM
That could be a possible cause.  :-\

I'd like to see what Black Sheep is able to suggest . . .
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 26, 2012, 04:20:30 PM
TBH ..... I've not got a damned clue. :'(

As FTTC/P is 'not my bag baby' (well, just not yet), then I really don't have much to go on ? Our old mucker BE has more idea than I, regarding all things Fibre.

Having read on this forum with interest about cross-talk being more prevalent on FTTC, and as such, down-grading the circuits, I can't help wondering if it's this that is the cause of all BE's woes ??

As I say, I genuinely don't know.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 26, 2012, 10:17:21 PM
Well, just for the hell of it, I swapped the modem & power supply at around 10:40 this morning.

Whether it was the modem swap, or just a new connection, apart from one connection re-sync at 16:00 this afternoon (following another drop in DS SNRM level), the connection has seemd O.K. at a sync speed of only 28.5Mb though.

The phone can now be used again without large SNRM drops.

I did phone home a few times from work today (whilst watching the modem's GUI remotely via LogMeIn), so I suppose the ringing pulses might have also caused a "fix" (maybe of a temporary nature as I have read about in various places).

In a way, I was hoping the connection would fail completely so that an engineer would have to deal with what may or may not have been an intermittent line fault.
Time will no doubt tell...................
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 27, 2012, 07:00:51 AM
I plugged the faceplate back into the master socket, reconnecting the internal wiring.

The connection has stayed up since swapping the modem, but DS SNRM dropped in the early hours to a low of 2.1dB.

Strangely, picking up the telephone this time immediately increased DS SNRM to 5.3dB.
Picking up the phone again dropped it to 4.6dB.

Hanging up the phone increased DS SNRM to 5.6dB & it is currently 5.8dB.

An incoming call reduced DS SNRM to 5.1dB & it returned to 5.8dB when the call was terminated.

Does any of that suggest anything problem-wise?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 27, 2012, 07:53:01 PM
Yes.  :)

Oh, do you want me to continue?  :P  O.k. One or more manky joints.

Do you have the loop attenuation available for the same time periods, when the telephone was used?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 27, 2012, 09:28:24 PM

Do you have the loop attenuation available for the same time periods, when the telephone was used?



Unfortunately not.

However, I can see that attenuation has generally increased a little, particularly in the U1 & D2 bands.

Code: [Select]
03/02/2012
==========

Path: 0, Upstream rate = 6160 Kbps, Downstream rate = 28721 Kbps

       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6198 kbps         33104 kbps
Actual Aggregate Tx Power:        6.2 dBm          12.0 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 52.3 63.7   N/A 21.4 62.5 0.1
Signal Attenuation(dB): 14.8 51.7   N/A   N/A 21.4 62.5   N/A
        SNR Margin(dB): 6.1 6.2   N/A   N/A 5.8 5.7   N/A
         TX Power(dBm): -4.2 5.8   N/A   N/A 11.0 5.5   N/A







27/03/2012
==========

Path: 0, Upstream rate = 5472 Kbps, Downstream rate = 28346 Kbps

       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       5502 kbps         33280 kbps
Actual Aggregate Tx Power:        6.3 dBm          12.1 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 53.7 64.0   N/A 21.9 63.9 0.1
Signal Attenuation(dB): 14.4 53.0   N/A   N/A 21.9 63.9   N/A
        SNR Margin(dB): 6.0 6.2   N/A   N/A 6.1 6.3   N/A
         TX Power(dBm): -4.2 5.8   N/A   N/A 11.1 5.8   N/A
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 27, 2012, 10:18:02 PM
Aha,

Found one - where DS SNRM dropped to very low levels & attainable rate was quite a bit less than sync speed.

Also, there's the attenuation over frequency graph with the dip in it again (right where bits stop being loaded).

Code: [Select]

Max: Upstream rate = 5509 Kbps, Downstream rate = 24820 Kbps
Path: 0, Upstream rate = 5520 Kbps, Downstream rate = 27089 Kbps

       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       5509 kbps         24820 kbps
Actual Aggregate Tx Power:        6.3 dBm          11.9 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.4 53.7 63.9   N/A 21.7 63.8 0.1
Signal Attenuation(dB): 14.2 53.0   N/A   N/A 21.7 63.8   N/A
        SNR Margin(dB): 6.0 6.1   N/A   N/A 1.8 1.9   N/A
         TX Power(dBm): -3.9 5.8   N/A   N/A 11.0 5.2   N/A
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 27, 2012, 11:44:51 PM
One or more manky joints in your D-side metallic path seem to be a reasonable assumption.

Knowing how you like to plot (almost) everything against time, I was hoping you would have the data to graph the Line Attenuation (dB) D1, D2 & D3 against time. If you could show me graphs of Line Attenuation v time & SNR v time that both have anomalies present and co-incident with a telephone being used, then I would suggest that you show the same to Alex (of PlusNet).

Putting it another way, show me and, more, importantly PlusNet & Openreach a smoking gun.  :-\

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 28, 2012, 06:12:57 AM
One or more manky joints in your D-side metallic path seem to be a reasonable assumption.

Knowing how you like to plot (almost) everything against time,

 :lol: :lol:

Quote
I was hoping you would have the data to graph the Line Attenuation (dB) D1, D2 & D3 against time.

If you could show me graphs of Line Attenuation v time & SNR v time that both have anomalies present and co-incident with a telephone being used, then I would suggest that you show the same to Alex (of PlusNet).

Putting it another way, show me and, more, importantly PlusNet & Openreach a smoking gun.  :-\

Attenuation is the tricky one.
As you know, the HG612 shows zero for overall DS & US attenuation in its GUI & various other xdslxmd info --xxxxx data.
It does show it per band in pbParams, from which I haven't been collecting "Ongoing" every minute data for my graphs.

Maybe I should start collecting that ongoing data too. I was under the impression it was only updated at each re-sync. Hence only obtaining it as & when a "snapshot" graph felt appropriate.

SNRM now seems to have stabilised again since yesterday & doesn't alter when using the phone.

I wonder if the more than normal use of the phone while testing has created a temporary fix by sending pulses of power up/down the copper line?

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 28, 2012, 12:03:27 PM

I wonder if the more than normal use of the phone while testing has created a temporary fix by sending pulses of power up/down the copper line?


Well, if it was a temporary fix, it was very temporary.

The connection re-synced again at 08:30 this morning at only just over 21Mb sync speed.

Attenuation has increased again & now I only get anything at all from DS band D1:-

Code: [Select]
Max: Upstream rate = 6015 Kbps, Downstream rate = 29240 Kbps
Path: 0, Upstream rate = 6004 Kbps, Downstream rate = 21172 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6015 kbps         29240 kbps
Actual Aggregate Tx Power:        6.3 dBm          10.9 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.4 54.0 64.0   N/A 22.1 64.1 0.1
Signal Attenuation(dB): 10.7 53.3   N/A   N/A 22.1   N/A   N/A
        SNR Margin(dB): 6.0 6.1   N/A   N/A 10.3   N/A   N/A
         TX Power(dBm): -4.1 5.8   N/A   N/A 10.9   N/A   N/A

This MIGHT be good news as surely Plusnet/BT now have to accept that my connection has physical faults that need investigating & fixing.

After the re-sync, DS SNRM was around 10dB for a few minutes, then it dropped to 2.5dB & simply picking up the handset caused it to shoot back up to around 10dB.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: smurfuk on March 28, 2012, 02:50:59 PM
Pure hunch, but what's the betting an HR fault has been introduced on to the line by some dodgy workmanship previously undertaken by OR, probably close to your premises? I had a case where BT swore blind that couldn't be, spending ££s on everything else then discovering my line cable had been "nipped" in the course of earlier work (after 2 years worth of fault investigation). Nights are still cold with heavy dew. Perhaps they could do worse than check, but I bet they won't.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 28, 2012, 04:10:16 PM
Ahem .......... trapped (or nipped) wires, does not automatically infer "Dodgy workmanship", Smurf. Does the word 'Accidentally' register in your mind ??

I'm not going 'on one' here, just yet again if some unsuspecting soul reads this, they may make the assumption ALL OR work is dodgy. That is just not the case.

There's only one man that never made a mistake, and they put him on a cross.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 28, 2012, 05:50:06 PM
@ Black Sheep,

In your experience, does attenuation generally tend to increase during warm, dry weather anyway?

I couldn't see my connection stats last summer, but that was when the problems started (21st July onward).

I didn't seem to do quite as badly during the wet & cold winter months (November until the very recent warm & dry spell).

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 28, 2012, 06:51:44 PM
@ Black Sheep,

In your experience, does attenuation generally tend to increase during warm, dry weather anyway?

I couldn't see my connection stats last summer, but that was when the problems started (21st July onward).

I didn't seem to do quite as badly during the wet & cold winter months (November until the very recent warm & dry spell).

Paul.

Again, I'll be honest and say I've not noticed BE. But then again, I wouldn't be looking in that respect anyway.

I have, (on average), just two hours to pick-up, note down, drive to, locate and fix,PQT and Eclipse, make a co-op call to ISP,test and demo to EU, and then fill the job notes in on my laptop. We just don't have the time to perform comparison tests on circuits, regarding their behaviour in differing climates.

When we pick-up the fault, if there has been a 'greater than 6dB' change to the attenuation from original readings, then we are made aware, other than that we just go about our usual business. I've never, ever had or heard of any attenuation issues being caused by heat, especially in this country.

I daresay that, like heat affects resistance readings, it will probably affect attenuation readings as well. To what degree (pardon the pun pal), I've no idea.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 30, 2012, 02:23:52 PM
Good news - Plusnet now appear to be arranging another engineer's visit as they confirm that SNRM shouldn't drop & cause re-syncs just by picking up a telephone handset.

Bad news - the ongoing but "intermittent" problem appears to have (temporarily?) subsided from 08:30 this morning.
Following yet another (uninitiated by me) re-sync in the early hours of this morning, my sync speed is currently 24999 k - SNRM 8.3dB, which looks suspiciously like DLM has capped it (probably due to all the disconnections over the last few days), needing another reset.

If only an engineer could have visited during this week - when the apparently intermittent problem may well have been a bit/lot easier to track down............................
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Blackeagle on April 02, 2012, 09:25:21 PM
@ Black Sheep,

In your experience, does attenuation generally tend to increase during warm, dry weather anyway?

I couldn't see my connection stats last summer, but that was when the problems started (21st July onward).

I didn't seem to do quite as badly during the wet & cold winter months (November until the very recent warm & dry spell).

Paul.

Hi BE, BE here  :lol: :lol:

Being quite OCD with my (currently ADSL line but soon to be fibre !), I monitor my stats all the time.  I have to say, I have never seen my attenuation vary at all, but then given that loop loss is approx 13.5dB per Km of cable, the line would have to increase by 800 metres to increase the attenuation by 1dB.  Obviously, this ain't gonna happen !!

In spite of the higher frequencies in use by VDSL, I would hazard that the general principle is the same and that attn should not vary, or not by any significant amount anyway.  Therefore, I would lean towards the 'dodgy joint' scenario in your particular case.  Now, given that you say it is worse in warm weather, I would tend to think it is overhead rather than underground.  Underground I would have thought would have been more susceptible to water ingress during bad weather rather than affected by heat.  Heat would, to my mind anyway, expand a joint slightly and this could be enough to affect the attn.  I've seen this scenario often enough in the field I work in, where a bad solder joint can be perfectly conductive at 10c yet not at 25c.  A can of freezer spray can prove an invaluable tool !!

All this though is based on ADSL systems and observations of many lines.  It may or may not apply to VDSL.  When my line is finally VDSL'd (5th April), I may be able to help you further (assuming that I get the Huawei modem  ;))

Best wishes

Blackeagle
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 03, 2012, 07:57:23 AM
Hi BE,


When my line is finally VDSL'd (5th April), I may be able to help you further (assuming that I get the Huawei modem  ;))


Fingers crossed for you for 5th.

Hopefully, all will be revealed regarding my connection when the engineer visits.
Although not confirmed yet, I am hoping it will be this week & also hoping the issue hasn't disappeared by the time of the visit (the weather is cooler & is expected to get even colder/wetter during the week).

The changes in temperature may just be coincidence though as since being able to see my stats my connection has never been what I would describe as stable (especially when compared against other users' stats - even those with much longer lines than mine).

Cheers,

BE.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 03, 2012, 04:24:27 PM
Hi Paul, sorry for the long delay, I don't really use the graphs because I was supplied with the ECI modem and that doesn't give me any stats, because as you know they can't be unlocked yet.

I have an Engineer coming tomorrow morning, this is the replay I got from my isp via email, "Wed AM slot has been booked for an FTTC1 engineer.
The Service Test failed due to mean time between errors which may indicate just a noise issue to the engineer so I have put notes on job to advise intermittent sync and drops in throughput are being experienced".

Can you or Black Sheep recommend me to request the Engineer to do or run any specific tests? Maybe if I get my connection sorted, It could also help you if they did the same at your end.

Hope it gets fixed for both of us mate,

All the best,

Josh. 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 03, 2012, 05:00:16 PM
Hi Josh. Mean Time Between Errors (MTBE), is basically illustrating that there is a problem somewhere. Be that with the Exchange equipment, OR's plant or your own equipment, I can't say.

I would request the engineer plug his EXFO/JDSU into the circuit and monitor the error-count. I would ask him to ring the landline number at the same time as monitoring. Also request theyperform a 'Quiet Line test', again, at the same time as monitoring for error-count.

You may get an experienced engineer who has the ability to locate a fault without asking ??
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 03, 2012, 05:23:28 PM
Hi Josh. Mean Time Between Errors (MTBE), is basically illustrating that there is a problem somewhere. Be that with the Exchange equipment, OR's plant or your own equipment, I can't say.

I would request the engineer plug his EXFO/JDSU into the circuit and monitor the error-count. I would ask him to ring the landline number at the same time as monitoring. Also request theyperform a 'Quiet Line test', again, at the same time as monitoring for error-count.

You may get an experienced engineer who has the ability to locate a fault without asking ??

I will show him these notes, hopefully I will get an experienced one this time, does FTT1 Engineer mean anything to you or is that just a standard one trained to work on Fibre?

Thanks Black Sheep!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 03, 2012, 06:15:29 PM
@ Black Sheep,

I would request the engineer plug his EXFO/JDSU into the circuit and monitor the error-count. I would ask him to ring the landline number at the same time as monitoring. Also request theyperform a 'Quiet Line test', again, at the same time as monitoring for error-count.

Which type of errors will the engineer be looking for?
Error types appear to change, depending on whether Interleaving is ON or OFF.

Strangely, with all the issues my connection has experienced (& is still experiencing) DLM has recently decided to turn Interleaving OFF.
Whether Interleaving is ON or OFF dictates the type of errors.
e.g. with Interleaving OFF, there is no Forward Error Correction (FEC).

Also with Interleaving OFF, Error Seconds increase (no doubt as errors are no longer forwardly corrected).
(See my attached 8 day graphs that demonstrate this - the SNRM dips are all caused by using the telephone, sometimes resulting in a connection re-sync).


Quote

You may get an experienced engineer who has the ability to locate a fault without asking ??


Even in Oldham?

I have to wonder if the pre-visit notes from ISPs are actually sufficiently clear, or whether or not those notes actually get passed to the engineer.

I can sort of understand why "some" engineers decline "some" end users' requests e.g. "While you are here, could you please conduct a TDR test as my connection appears to have an intermittent HR issue & by the way, would you like brown sauce on your bacon butty?"

My engineer's visit is provisionally booked for Saturday morning (awaiting confirmation).

I really hope the intermittent issue(s) I am currently experiencing haven't intermittently bu@@ered off again before then.



@ JoshShep,

Good luck for tomorrow's visit.

Is there any pattern emerging that you could mention to the engineer regarding your "intermittent sync and drops in throughput"?
e.g. time of day, heating switched on, use of a hairdryer, an old fridge motor switching on/off, use of the phone, the sky box using the phone line to order a film, sudden or gradual change in prevailing weather conditions/temperatures, next door neighbour is a Radio Ham & when he is transmitting you can see "interference" lines on your TV etc. etc. etc.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 03, 2012, 06:28:09 PM
@ Black Sheep,

I would request the engineer plug his EXFO/JDSU into the circuit and monitor the error-count. I would ask him to ring the landline number at the same time as monitoring. Also request theyperform a 'Quiet Line test', again, at the same time as monitoring for error-count.

Which type of errors will the engineer be looking for?
Error types appear to change, depending on whether Interleaving is ON or OFF.

Strangely, with all the issues my connection has experienced (& is still experiencing) DLM has recently decided to turn Interleaving OFF.
Whether Interleaving is ON or OFF dictates the type of errors.
e.g. with Interleaving OFF, there is no Forward Error Correction (FEC).

Also with Interleaving OFF, Error Seconds increase (no doubt as errors are no longer forwardly corrected).
(See my attached 8 day graphs that demonstrate this - the SNRM dips are all caused by using the telephone, sometimes resulting in a connection re-sync).


Quote

You may get an experienced engineer who has the ability to locate a fault without asking ??


Even in Oldham?

I have to wonder if the pre-visit notes from ISPs are actually sufficiently clear, or whether or not those notes actually get passed to the engineer.

I can sort of understand why "some" engineers decline "some" end users' requests e.g. "While you are here, could you please conduct a TDR test as my connection appears to have an intermittent HR issue & by the way, would you like brown sauce on your bacon butty?"

My engineer's visit is provisionally booked for Saturday morning (awaiting confirmation).

I really hope the intermittent issue(s) I am currently experiencing haven't intermittently bu@@ered off again before then.



@ JoshShep,

Good luck for tomorrow's visit.

Is there any pattern emerging that you could mention to the engineer regarding your "intermittent sync and drops in throughput"?
e.g. time of day, heating switched on, use of a hairdryer, an old fridge motor switching on/off, use of the phone, the sky box using the phone line to order a film, sudden or gradual change in prevailing weather conditions/temperatures, next door neighbour is a Radio Ham & when he is transmitting you can see "interference" lines on your TV etc. etc. etc.

Thanks BE, only thing I can think of is when the weather is dry my connection seems to be more unstable and I have a lower sync, rain seems to do my connection good.

I don't really know about the other things I will have to monitor, what is a TDR test? I think the Engineer will run one if I request he's been quite good actually, that being if it's the same one  :-\

Is the TDR equipment in there standard kit?

Thanks,

Josh
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 03, 2012, 07:00:04 PM

Thanks BE, only thing I can think of is when the weather is dry my connection seems to be more unstable and I have a lower sync, rain seems to do my connection good.


Mine too, but that COULD be pure coincidence.

Quote

I don't really know about the other things I will have to monitor, what is a TDR test? I think the Engineer will run one if I request he's been quite good actually, that being if it's the same one  :-\

Is the TDR equipment in there standard kit?


Perhaps Black Sheep could provide a more detailed response, but very basically it is a test that can be conducted using a JDSU (standard engineer's equipment) or "other" specialised equipment that can detect various types of line faults that the usual basic tests such as Pair Quality Test (PQT) often don't detect.

A TDR test that finds a "fault" will also report an approximation of the distance from the testing point etc.

It may different in the area where you are located, but up here in Oldham, visiting engineers appear to have great reluctance (even to the point of a blank refusal) when asked to coduct a TDR test.
Maybe they are not allowed sufficient time per job?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: c6em on April 03, 2012, 07:16:21 PM
In laymans' language....
TDR Test (Time Domain Reflectometer)
It injects a very very very short electrical impulse into the cable and by measuring very accurately the nature of the reflections received as this pulse bounces back to the instrument from the imperfections (if any) in the cable you can locate the distance of the imperfection from the instrument on the end of the cable.  If you are suitably trained to interpret the waveform trace on the screen of the instrument you can determine the nature of the imperfection on the cable - which might be the obvious direct short/open circuit as well as the dreaded High Resistance fault.
It does require you to know correctly the type of cable being analysed to get accurate results and most tester have some sort of drop down box to choose the cable type (copper/al/conductor size/insulation type etc). cables with multiple cable types in the overall length will also be found as the pulse will reflect back from the change in conductor where it joins.

This sort of specialist instruments don't come cheap - They will be in the £3000+ region as a wild guess but will also need a professional recalibrate once a year as well.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 03, 2012, 07:27:37 PM

It does require you to know correctly the type of cable being analysed to get accurate results and most tester have some sort of drop down box to choose the cable type (copper/al/conductor size/insulation type etc). cables with multiple cable types in the overall length will also be found as the pulse will reflect back from the change in conductor where it joins.


Could any/every engineer confirm the cable type(s) for individual connections (maybe from BT's Network Records)?

I did ask a visiting engineer if my connection included any aluminium cabling.
His response was "probably", but he wasn't exactly the most helpful of engineers.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 03, 2012, 07:31:32 PM
In laymans' language....
TDR Test (Time Domain Reflectometer)
It injects a very very very short electrical impulse into the cable and by measuring very accurately the nature of the reflections received as this pulse bounces back to the instrument from the imperfections (if any) in the cable you can locate the distance of the imperfection from the instrument on the end of the cable.  If you are suitably trained to interpret the waveform trace on the screen of the instrument you can determine the nature of the imperfection on the cable - which might be the obvious direct short/open circuit as well as the dreaded High Resistance fault.
It does require you to know correctly the type of cable being analysed to get accurate results and most tester have some sort of drop down box to choose the cable type (copper/al/conductor size/insulation type etc). cables with multiple cable types in the overall length will also be found as the pulse will reflect back from the change in conductor where it joins.

This sort of specialist instruments don't come cheap - They will be in the £3000+ region as a wild guess but will also need a professional recalibrate once a year as well.

Very interesting smurfuk, sounds like an advanced test. I will request the Engineer to run this and hopefully it will pinpoint the issue. That being if he hasn't already run this test.

Thanks!

Josh
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 03, 2012, 07:37:46 PM
Hi BE ...... to answer your question, he should be looking at not just retransmitted errors (CRC's/Errored Seconds), but also if Interleaving is applied the FEC's ....... or rather, the rate of incrementation of FEC's. There isn't an integer that we say "Right, it's passed 'X' ammount of FEC's, there's a fault somewhere". You just kinda know it isn't right.

TDR ........ c6em has covered that more than adequately, but if I may add that when actually using the TDR 'we' don't input the cable gauges into the tester. The trace is looked at over the entire distance of the line and conclusions drawn. If it's a Short Circuit, it'll present itself as a 'trough' (Much like the letter 'V'), if it's a 'HR' it shows as a 'peak' ( An inverted 'V'). The trick comes with interpreting the results in relation to cable poundage changes, as miniscule versions of peaks and troughs can appear especially if the poundage change is severe, EG- 0.32-0.64 mm. Cross-referencing can be done against our Network Records for changes in cable sizes, but the experienced engineer should be able to seperate the two.

I always ring the landline whilst the trace is running as this will show a 'HR' that is in its infancy, that a dormant trace wouldn't pick up.

I have a JDSU and they are the bees-knees of the testing fraternity. better IMO than the EXFO that other engineers are always finding fault with. The only down side to the JDSU though is its TDR function, especially at near distances. Thankfully I still have my HAWK for that purpose.

I think it was BE that alluded to timescales on the task ?? Absolutely there are. As a business, there has to be stats and targets to achieve, most know my (and others) take on this, but it is what it is. 2hrs of task time is usually applied to this type of job.

Best of luck. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 03, 2012, 07:39:10 PM
In laymans' language....
TDR Test (Time Domain Reflectometer)
It injects a very very very short electrical impulse into the cable and by measuring very accurately the nature of the reflections received as this pulse bounces back to the instrument from the imperfections (if any) in the cable you can locate the distance of the imperfection from the instrument on the end of the cable.  If you are suitably trained to interpret the waveform trace on the screen of the instrument you can determine the nature of the imperfection on the cable - which might be the obvious direct short/open circuit as well as the dreaded High Resistance fault.
It does require you to know correctly the type of cable being analysed to get accurate results and most tester have some sort of drop down box to choose the cable type (copper/al/conductor size/insulation type etc). cables with multiple cable types in the overall length will also be found as the pulse will reflect back from the change in conductor where it joins.

This sort of specialist instruments don't come cheap - They will be in the £3000+ region as a wild guess but will also need a professional recalibrate once a year as well.

Very interesting smurfuk, sounds like an advanced test. I will request the Engineer to run this and hopefully it will pinpoint the issue. That being if he hasn't already run this test.

Thanks!

Josh

It's completely the opposite Josh, it's the simplest of tests to perform.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 03, 2012, 08:21:43 PM
Ok thanks for that Black Sheep, much appreciated!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 03, 2012, 08:36:19 PM

It does require you to know correctly the type of cable being analysed to get accurate results and most tester have some sort of drop down box to choose the cable type (copper/al/conductor size/insulation type etc). cables with multiple cable types in the overall length will also be found as the pulse will reflect back from the change in conductor where it joins.


Could any/every engineer confirm the cable type(s) for individual connections (maybe from BT's Network Records)?

I did ask a visiting engineer if my connection included any aluminium cabling.
His response was "probably", but he wasn't exactly the most helpful of engineers.

Depends on the engineers knowledge pal. If he's a CAL/OMI background, chances are he won't know what Network Records even are. If he's 'Multi-skilled', then yes he should know how to find the relevant info from the Network Records. For your info  ;) ............ it's in the top left hand corner of the application, next to the 'Duct' button. Just in case you get a friendly engineer. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 03, 2012, 08:36:53 PM
Ok thanks for that Black Sheep, much appreciated!

No worries pal. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 03, 2012, 11:38:19 PM
Depends on the engineers knowledge pal. If he's a CAL/OMI background, chances are he won't know what Network Records even are. If he's 'Multi-skilled', then yes he should know how to find the relevant info from the Network Records. For your info  ;) ............ it's in the top left hand corner of the application, next to the 'Duct' button. Just in case you get a friendly engineer. ;D

Thanks for that BS.

TBH, as an end user, I shouldn't really need to know any of this stuff.

I should just be able to say something on the lines of "My connection was brilliant, but since it all went off for a few days it has been really poor. Please fix it."

It is only the comments such as "LTOK" when clearly it hasn't been O.K. & "performing within acceptable limits" etc. over quite a few months that has made me look deeper into potential causes.

Also, the explanation of peaks & troughs as shown in a TDR trace was interesting (reflections).
I expected the complete opposite i.e. that a HR fault would show as increased attenuation (a dip or valley), as occasionally displayed in my connection's Hlog graphs:-

(http://i1255.photobucket.com/albums/hh629/Bald_Eagle1/Hlog-20120325-2047.png)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 03, 2012, 11:59:12 PM
Quote
Also, the explanation of peaks & troughs as shown in a TDR trace was interesting (reflections).
I expected the complete opposite i.e. that a HR fault would show as increased attenuation (a dip or valley), as occasionally displayed in my connection's Hlog graphs:-

You can have it "the other way up". Just invert the Y-axis!  :P

(It really depends upon what is being plotted against what . . . whether one sees a peak or a trough is not too relevant when one is just looking for an abnormality.)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 04, 2012, 10:30:50 AM
Update: Engineer has been, first he found no faults, and then I asked him to run a TDR Test, he pinpointed a issue 72 metres away, that resulted to the top of the telephone pole. He changed the connection module and found it improved things, run some more tests, rang the phone as doing the tests, all come back fine. I then requested a profile reset which he did, now currently syncing at 40 meg, highest sync I've ever had, still as you know early days, but the next 72 hours will tell. Great bloke that listened to all I had to say, happy at the moment but that can all change, lol.

Fingers crossed! :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 04, 2012, 10:48:19 AM
Result.

Not many engineers will be aware, but the newer type BT18C boxes fitted at the top of the DP's (Telegraph poles) have the 'push connection' modules, that do what they say on the tin .......... you 'push' the right hand side of the insert and it 'connects' the UG (Underground) wires to it. The left-hand side of the module is still a screw-terminal where the Dropwire terminates.

The issue with these 'push types' is that a percentage of the existing D-side cable feeding the DP's will be in the 0.32/0.4 mm region. These DO NOT terminate as well as they should, and cause a miniscule HR-type of fault. What should be done is that the existing UG feed be 'gel crimped' to a short piece of 0.5mm Cu wiring, and then connect this to the 'push fit' side of the module.

I've probably had half-a-dozen of these issues in recent history, but they were a pain to localise in the early days as they wouldn't 'appear' on the TDR screen as a 'HR'. Just sheer perseverance located the fault.  .
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 04, 2012, 10:58:10 AM
Update: Engineer has been, first he found no faults, and then I told him to run a TDR Test, he pinpointed a issue 72 metres away, that resulted to the top of the telephone pole. He changed the connection module and found it improved things, run some more tests, rang the phone as doing the tests, all come back fine. I then requested a profile reset which he did, now currently syncing at 40 meg, highest sync I've ever had, still as you know early days, but the next 72 hours will tell. Great broke that listened to all I had to say, happy at the moment but that can all change, lol.

Fingers crossed! :)

Hey JoshShep,

That's fantastic news :drink: :drink:

The engineer does indeed sound like a great bloke, willing to listen to an end user's concerns & react accordingly.
(very much in the same vein that I suspect a certain BS & one or two other engineers approach customer service)

Fingers crossed that it's a permanent improvement.

Just for reference:-

   What was your previous highest sync speed?
   Which equipment did he use for the TDR test?
   Did the engineer re-run a TDR test to look for any other "issues" after fixing the one found at 72 metres?
   Did you manage to see the reported line length, both before & after the repair work (or even snatch a photo of the instrument displays)?

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 04, 2012, 11:32:26 AM
Update 04/04/2012:

My own engineer's visit is now confirmed for Saturday am.

Email just received from Alex at Plusnet:-
"BT have confirmed the appointment for 07/04/12 AM.
I will add notes for checks for High Resistance and if possible the completion of a TDR or FDR test."

Hopefully, these notes will actually be passed on to the visiting engineer.

Not knowing for sure what a FDR test was, I looked it up:-

"Frequency Domain Reflectometers (FDR) test cable at specific frequencies or frequency bands. 
Time Domain Reflectometers (TDR) test a cable against the manufacturer’s Characteristic Impedance, which basically tests the cable for any and all frequencies."

If there is any issue with the engineer being uncertain which specific frequencies to test for the FDR test, I'll whip out my Hlog graphs as a last resort.

However, after all these months of intermittent instability I now basically want/need the whole lot testing (& RE-TESTING AFTER ANY WORK IS CARRIED OUT).

Who knows, 40 Mb may just be on the horizon  ;) :-\
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 04, 2012, 11:52:38 AM
Hmmm ?? FDR ??

A guess at this, but it could be the CIDT test that some circuits are tested under ?? This is the basic low-frequency 'Fast Test' that all lines are tested under, then it performs the 3'rd test which has to be against a plugged-in router. It basically 'sends' different tones (Frequencies) to and from the router and then gives a final result.

Just a guess
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 04, 2012, 12:43:52 PM
Hmmm ?? FDR ??

A guess at this, but it could be the CIDT test that some circuits are tested under ?? This is the basic low-frequency 'Fast Test' that all lines are tested under, then it performs the 3'rd test which has to be against a plugged-in router. It basically 'sends' different tones (Frequencies) to and from the router and then gives a final result.

Just a guess

Who knows?
Who cares? (as long as it all gets fixed on Saturday).


Thanks for your useful snippets of info again, especially the "newer type BT18C boxes fitted at the top of the DP's".

Another one to keep up our sleeves (..........just in case........)  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: covlad1987 on April 04, 2012, 01:42:57 PM
sticking my nose in this one can i ask what this is pls "newer type BT18C boxes
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 04, 2012, 02:13:07 PM
Bald_Eagle ....... no worries mate. I know you and some of the other guys appreciate the feedback.  :-[ :)

covlad ..... the 'newer types' are what we locally refer to as 'Coffin lids'. They are larger in size than any of the other we utilize. They look rectangular with small arcs on the two shoulders. Basically, probably nothing like that crap description I've given !!!  :lol:

Perhaps one of the others has time to post up a picture of one ???

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 04, 2012, 02:29:15 PM
Result.

Not many engineers will be aware, but the newer type BT18C boxes fitted at the top of the DP's (Telegraph poles) have the 'push connection' modules, that do what they say on the tin .......... you 'push' the right hand side of the insert and it 'connects' the UG (Underground) wires to it. The left-hand side of the module is still a screw-terminal where the Dropwire terminates.

The issue with these 'push types' is that a percentage of the existing D-side cable feeding the DP's will be in the 0.32/0.4 mm region. These DO NOT terminate as well as they should, and cause a miniscule HR-type of fault. What should be done is that the existing UG feed be 'gel crimped' to a short piece of 0.5mm Cu wiring, and then connect this to the 'push fit' side of the module.

I've probably had half-a-dozen of these issues in recent history, but they were a pain to localise in the early days as they wouldn't 'appear' on the TDR screen as a 'HR'. Just sheer perseverance located the fault.  .

Sounds like it did the trick, we will know in the next few days, I felt sorry for him up there in the snow!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 04, 2012, 02:40:48 PM
Update: Engineer has been, first he found no faults, and then I told him to run a TDR Test, he pinpointed a issue 72 metres away, that resulted to the top of the telephone pole. He changed the connection module and found it improved things, run some more tests, rang the phone as doing the tests, all come back fine. I then requested a profile reset which he did, now currently syncing at 40 meg, highest sync I've ever had, still as you know early days, but the next 72 hours will tell. Great broke that listened to all I had to say, happy at the moment but that can all change, lol.

Fingers crossed! :)

Hey JoshShep,

That's fantastic news :drink: :drink:

The engineer does indeed sound like a great bloke, willing to listen to an end user's concerns & react accordingly.
(very much in the same vein that I suspect a certain BS & one or two other engineers approach customer service)

Fingers crossed that it's a permanent improvement.

Just for reference:-

   What was your previous highest sync speed?
   Which equipment did he use for the TDR test?
   Did the engineer re-run a TDR test to look for any other "issues" after fixing the one found at 72 metres?
   Did you manage to see the reported line length, both before & after the repair work (or even snatch a photo of the instrument displays)?

Thanks mate :drink: To answer your question BE,

1) My previous highest sync for 37 so nothing major there but since my drop wire was replaced it had gotten worse.
2) He used the standard kit that gives you results for sync speed and errors, excuse me, I have no idea what the there called.
3)Yes I asked him to re run the test when he had done the repair and he said it looked much better, and showed me a graph where there was a spike where the cable pair changed, the spike was much smaller this time.
4)And no sorry I didn't manage to.

Regards,

Josh

Edit, the tool he used was like a JDSU, but the other one. Very similar

Hope everything goes well for Sat! :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 04, 2012, 04:56:25 PM
Quote
Edit, the tool he used was like a JDSU, but the other one. Very similar

I guess, then, he must have used an Exfo.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 04, 2012, 05:10:43 PM
Quote
Edit, the tool he used was like a JDSU, but the other one. Very similar

I guess, then, he must have used an Exfo.  :)

That's the one! :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 04, 2012, 05:17:20 PM
Quote
That's the one! :)

Yay!  :thumbs:  :dance:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: covlad1987 on April 04, 2012, 06:30:34 PM
Bald_Eagle ....... no worries mate. I know you and some of the other guys appreciate the feedback.  :-[ :)

covlad ..... the 'newer types' are what we locally refer to as 'Coffin lids'. They are larger in size than any of the other we utilize. They look rectangular with small arcs on the two shoulders. Basically, probably nothing like that crap description I've given !!!  :lol:

Perhaps one of the others has time to post up a picture of one ???

are thay on top of the pole lol if so im looking at 1 right now right out side my home
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 04, 2012, 06:38:42 PM
They can be placed on top of poles, on external walls and even seen them on internal installations, (which is just sooooo wrong  ;D).

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 04, 2012, 06:51:57 PM
Well, I've half-succeeded in my quest.  ::)

The picture of the Box Conn is exactly the one we use, as mooted previously. However, the picture of the module is not what we use, and is only to give a rough idea of what they look like.
Whereby in the picture both sides of the module are 'Screw-fix', the ones we use are 'Push-fix' for the UG connection. It is this that causes the issues with lower than 0.5mm poundage cable, as there is a bit of a 'spring back' on the connector regardless of how hard one pushes.

Hope this gives a better insight as to what I'm waffling on about ?? ???
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 07, 2012, 02:36:30 PM
Update 07/04/2012:

Whilst awaiting the engineer for this morning's visit, I noticed my connection drop for a few minutes.

When the engineer (Tyrone) arrived, he explained that the purpose of his visit was to check for HR faults & to investigate dropping SNRM levels & occasional disconnections while the phone was in use.

He said that he hadn't been made aware of the long-standing issues, but he would be checking everything he could to try to get to the bottom of them (even though this wasn't officially a "Boost" visit).

What's a Boost visit, anyone?

He confirmed he had run a TDR & a FDR test from the cabinet (hence the disconnection) & both looked exactly as they should.

He did mention he had spotted a small amount of corrosion on the connection in the cabinet, which he dealt with while he was there.

From my home Tyrone ran an Equal Leg balance test & confirmed good balance (both legs around a value of 12).

He also ran a TDR test from my home (unfortunately I didn't get a photo), which showed a gradual tailing off of the plot until a large peak, which he confirmed as the cabinet itself.

There was a bit of an upward "hump" (I missed the distance, but was perhaps 1/3 of the way from my house to the cabinet). However, Tyrone said that was quite normal & to be expected.

He also mentioned the lack of any other evidence which more or less confirmed a lack of Aluminium cabling which would have shown on the graph.

One Exfo screen reported a line length of 1155m, which he said was a known "bug" (supposedly being looked into by Exfo) & then Tyrone showed me another screen which confirmed a line length of 834m from the cabinet, which is apparently accurate to within a few metres & is the "real" length.
This 834m ties in with a previous engineer's comment that my connection was roughly 820m & NOT THE 1100m OR SO THAT HAS BEEN MENTIONED ELSEWHERE.

Various other tests all passed, with the exception of the insulation test which failed.
Tyone checked the crocodile connections & about 5mm of the end of one of the pairs in the drop wire snapped off.
I suppose this could/would have been the cause of the dropping SNRM issue?



Tyrone also brought his laptop in, specially so we could have a look at Network Records & I now have confirmation of my connection's actual route.
The last section goes past my house (underground) to a joint chamber & then comes back to the pole opposite my house.
Pacing it out, that adds 60m to my D-side.
I wonder how how much sync speed & stability is lost in those 60m  ::)  ;D


He had an Exfo tester, so I can't quite compare against any previous JDSU results from my connection.

These are the Exfo's stats (read out by Tyrone, but he said he was happy for me to take as many photos as I wished to):-

Code: [Select]

US DS
Actual Line Rate 6 24
Max Rate 6 33
Capacity 100% 75%
Noise Margin 6 9
Output 6.3 11.2
Loop Attenuation 7.9 31.6
Signal Attenuation 11 31.4

Now, the 31.6dB Loop Attenuation & 31.4dB Signal Attenuation (DS) bothered me a little as they have previously been reported as 23dB (from a JDSU) & when my connection was at its worst at 30.2dB.

However, as my connection was still capped by DLM at this stage, I thought I would wait until the modem was reconnected.
At least I would then be able to compare stats like-for-like.
The modem stats now show a slight reduction in DS attenuation (now more like the usual levels), which has allowed me to use some of the D2 frequency band again.

@BS, or any other engineers passing through:-

Is it usual to see large difference between Exfo & JDSU Attenuation readings?


Anyway, the HG612 was connected up & we had a look at its stats.
Sync speed was still at 24999k, so I asked Tyrone to phone through to get it re-set.

Watching SNRM while using the phone, resulted in a drop of only 0.2dB.
So it looks like replacing the master socket's filtered parts and/or the end of the drop wire cable snapping off and/or sorting out the slight corrosion on the connection at the cabinet has resolved the recent dropping SNRM & occasional disconnection.

On leaving, Tyrone said he would phone through from his van to get DLM re-set.

I did see a re-sync, with a resulting speed of 31115 k DS & 5795 k US.
That was a little disappointing as the previous re-set gave me a DS sync speed of 35322 k DS & 6372 k US.

A few minutes later, the phone went dead & the connection dropped.

Oh, no!
On checking, Tyrones van had gone.

5 minutes later, the phone came back on & the connection was restored, a tiny increase, but still disappointing at 31251 k DS & 5807 k US.

Tyrone then phoned, saying he had been sent to check that everything at the cabinet was 100% correct, so that was what had caused the disconnection.

He also mentioned that while he was on the phone to OMC (I think that what he called it), the gentleman at the other end had told him there was a long history of instability & low speed on my connection & that they believe there is still another underlying issue as I am not too far from the cabinet.

He told OMC that 79Mb was showing at the cabinet (I'm on Plusnet's 80Mb/20Mb trials at the moment) & they both agreed that I should be seeing somewhat better speeds & certainly more stability over the 834m.

I'm not sure how this has been left, so I will be contacting Plusnet to find out.

While he was still at my house, Tyrone mentioned the slight possibility of REIN being the cause of my connection's issues, but looking at my graphs, he more or less ruled it out as there was no discernible pattern to the frequent but irregularly timed disconnections/errors etc.

Without any prompting, Tyrone said he would provide fully detailed notes from today's visit.



I wish to record that Tyrone was the most polite, helpful & informative of engineers, talking me through everything he was doing & showing a genuine interest in anything I mentioned & showed him.
He seemed really interested in the unlocked modem's GUI & mentioned that enginners were only shown that during their initial fibre training session.

He even held out his hand for a handshake on arrival & again on his departure  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 08, 2012, 01:39:35 AM
You have clearly been visited by a most helpful and knowledgeable Openreach employee.  :thumbs: 

The saga continues . . . So we shall watch this space, with interest.  :)

[ At a personal level, if there are any sketches / maps / photographs / whatnots / etc as a result of Tyrone's visit, I trust that an e-mail message will be on its way (to The Cattery) as a carrier of the same.  ;)  ]
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: renluop on April 08, 2012, 06:50:16 AM
So it's Tyrone power that's done it! ;D

Note for  those of tenderer years only (http://en.wikipedia.org/wiki/Tyrone_Power) >:D ;)






Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 08, 2012, 06:56:05 AM
[ At a personal level, if there are any sketches / maps / photographs / whatnots / etc as a result of Tyrone's visit, I trust that an e-mail message will be on its way (to The Cattery) as a carrier of the same.  ;)  ]

TBH, I only have one photo (attached).

Regretfully I didn't take one of the TDR trace that may have been useful for experienced users to comment on, but I have attached a very rough sketch of its appearance.

I simply wrote down the important line length & connection stats (I can see my own stats for comparison of any changes anyway):-


Just before the visit:-

Code: [Select]
Max: Upstream rate = 6474 Kbps, Downstream rate = 28080 Kbps
Path: 0, Upstream rate = 6254 Kbps, Downstream rate = 24999 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6474 kbps         28080 kbps
Actual Aggregate Tx Power:        6.2 dBm          10.8 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.3 53.8 64.0   N/A 22.0 64.0 0.1
Signal Attenuation(dB): 11.0 52.7   N/A   N/A 22.0   N/A   N/A
        SNR Margin(dB): 6.3 6.3   N/A   N/A 8.9   N/A   N/A
         TX Power(dBm): -4.2 5.8   N/A   N/A 10.8   N/A   N/A



Engineer finished - awaiting DLM re-set:-

Code: [Select]
Max: Upstream rate = 5836 Kbps, Downstream rate = 31484 Kbps
Path: 0, Upstream rate = 5836 Kbps, Downstream rate = 24999 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       5836 kbps         31484 kbps
Actual Aggregate Tx Power:        6.3 dBm          11.4 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.1 53.3 65.1   N/A 21.9 63.6 0.1
Signal Attenuation(dB): 9.4 52.6   N/A   N/A 21.9 63.6   N/A
        SNR Margin(dB): 6.1 5.9   N/A   N/A 10.6 10.6   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.9 2.1   N/A



At the end of the visit (DLM Re-set):-

Code: [Select]
Max: Upstream rate = 5731 Kbps, Downstream rate = 31232 Kbps
Path: 0, Upstream rate = 5768 Kbps, Downstream rate = 31048 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       5731 kbps         31232 kbps
Actual Aggregate Tx Power:        6.3 dBm          12.0 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 53.4 64.7   N/A 21.9 63.6 0.1
Signal Attenuation(dB): 9.7 52.6   N/A   N/A 21.9 63.6   N/A
        SNR Margin(dB): 6.1 6.1   N/A   N/A 6.1 6.3   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.8 5.3   N/A



DLM Re-set of 9th March - highest sync speed since July 2011:-

Code: [Select]
Max: Upstream rate = 6376 Kbps, Downstream rate = 35864 Kbps
Path: 0, Upstream rate = 6372 Kbps, Downstream rate = 35322 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6376 kbps         35864 kbps
Actual Aggregate Tx Power:        6.2 dBm          12.2 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 53.0 64.1   N/A 21.6 63.2 0.1
Signal Attenuation(dB): 14.4 52.5   N/A   N/A 21.6 63.2   N/A
        SNR Margin(dB): 6.0 6.1   N/A   N/A 6.3 6.4   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.9 6.4   N/A


The changes are small, but appear to make enough difference to dictate which band plan(s) can be used (or not) & make a few Mb difference to sync speed.

Due to the recent disconnections/SNRM dropping issue, the stats from just before the visit are from when DLM had capped my sync speed at 24999k.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 08, 2012, 07:15:39 AM

So it's Tyrone power that's done it! ;D


 :lol: :lol:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 08, 2012, 07:28:28 AM
Hmmm,

I have just discovered that my connection had re-synced while I was typing my previous message.
It had been up for just over 18 hours.

I can't see any reason for this re-sync in my stats (low error counts, SNRM still at 4.9dB from its night time reduction) & no electrical equipment was turned on or off in my house at the time.

I didn't notice whether or not the street light about 3m from the pole where my drop wire starts switched off at that time.

We did discuss that particular pole & street light during yesterday's visit, along with coffin lids & patch cable tricks etc. (thanks BS - they call them coffin lids in Oldham too) & ruled it out as a potential REIN source as the frequent disconnections have not previously coincided with street light switching on & off times.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 08, 2012, 10:42:15 AM
So it's Tyrone power that's done it! ;D

Note for  those of tenderer years only (http://en.wikipedia.org/wiki/Tyrone_Power) >:D ;)

I was wondering who would be the first to make such an observation!  :silly:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on April 08, 2012, 11:20:34 AM
@ BS,

If you are able to identify Tyrone, I am sure that BE1 and every Kitz observer would like you to pass on our most grateful thanks and hearty congratulations to Tyrone's supervisor / coach.

This encounter must surely illustrate that only with full co-operation between the EU and O/R staff, and an unlocked modem, that these types of anomaly can be effectively cured as we all recognise what a horrible needle in a hay stack we are chasing.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 08, 2012, 12:03:10 PM
@ BS,

If you are able to identify Tyrone, I am sure that BE1 and every Kitz observer would like you to pass on our most grateful thanks and hearty congratulations to Tyrone's supervisor / coach.


FWIW, Tyrone started as an apprentice with BT & he thinks the guy who trained him was the very same guy who restored my 35Mb just a few weeks ago.

That was only a site visit to get DLM reset, but still.................
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 09, 2012, 11:27:06 AM
Hi, I have suprisingly managed to track down Tyrone's details. Thought it would be a 'needle in a haystack' task, with just having the first name and him being under a completely seperate Operational Unit.

Anyhows, if BE wishes to pass on his regards, I can supply the specific job number (Information that is in the public domain and could be requested by BE from his ISP) via PM, and BE would then have to approcah his ISP and request that they pass on the regards on his behalf. I'm not going to start dishing out engineers personal info on a public forum PM or otherwise i'm afraid, however good the intentions might be. :)
I'm sure you'll appreciate it could have all sorts of repercussions.  :-X ;) :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: covlad1987 on April 09, 2012, 11:57:48 AM
Well, I've half-succeeded in my quest.  ::)

The picture of the Box Conn is exactly the one we use, as mooted previously. However, the picture of the module is not what we use, and is only to give a rough idea of what they look like.
Whereby in the picture both sides of the module are 'Screw-fix', the ones we use are 'Push-fix' for the UG connection. It is this that causes the issues with lower than 0.5mm poundage cable, as there is a bit of a 'spring back' on the connector regardless of how hard one pushes.

Hope this gives a better insight as to what I'm waffling on about ?? ???

thats what on the pole out side my house lol
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 09, 2012, 11:59:42 AM
Thanks for that BS.

Plusnet's Alex has this morning confirmed he has read this thread's report of the visit & I have added suitable comments to the Plusnet fault ticket system anyway, so communicating job details etc. via PM won't be necessary.

Cheers,

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 09, 2012, 12:33:37 PM
Cheers BE. Have PM'd you anyway, regarding the benefits to the engineer of good EU feedback. No other details have been sent, as PNET have all the neccessary information as you state.  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: les-70 on April 09, 2012, 02:51:34 PM
 In case it is of any interest the document below is helpful for understanding TDR traces. See in particular the examples at the end .  The hump in your sketch look bit like a weak HR point in the cable??.  The big feature at the end is presumably the cable end.

 http://documents.exfo.com/appnotes/anote168-ang.pdf

  Also

 http://myaccount.flukenetworks.com/fnet/en-us/StreamIt?Document=9821102

   and no doubt others
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 10, 2012, 04:18:15 AM
The big feature at the end is presumably the cable end.

Er, no.  :no:  That is the FTTC DSLAM, which shows as a "now you see me, now you don't" "beacon" at 0.5 Hz. The boffins at "Grimbledon Down" specified that should be present, so as to allow the most junior of Field Service Operatives to be able to identify something, with certainty, in the TDR trace of a VDSL2 copper pair.  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: les-70 on April 10, 2012, 09:14:05 AM
  I assume you do mean the big feature at the end. I meant the end of the VDSL cable segment and should have been more precise.  I would guess that it must be at the FTTC DSLAM but don't know how they configure the DSLAM end of the cable for the test.  Do they use the TDR with the CAB DSLAM connected? or do they fully disconnect the  cable in  DSLAM CAB for the test?  I notice that at least some TDR test equipment advice is for a open end.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on April 10, 2012, 09:54:31 AM
@ les 70,

I hope BS will correct me if I'm wrong, but it's my understanding that "ordinary" BT O staff do not have access to FTTC cabinets (Unless they have been issued with the secure key) as I believe any VDSL modifications are only carried out in the associated PCP (or possibly on the associated cable joints if necessary).

Also FTTC cabinets around Guildford (and I believe other earlier version cabinets) have additional star shaped keys rather than the standard triangle ones. Later cabinets have reverted to the triangle ones.
(There's a nice easy overtime job for BS to go round swapping out the star keys !)

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 10, 2012, 10:28:56 AM
  I assume you do mean the big feature at the end. I meant the end of the VDSL cable segment and should have been more precise.  I would guess that it must be at the FTTC DSLAM but don't know how they configure the DSLAM end of the cable for the test.  Do they use the TDR with the CAB DSLAM connected? or do they fully disconnect the  cable in  DSLAM CAB for the test?  I notice that at least some TDR test equipment advice is for a open end.

Yes, the big feature was indeed the cabinet. I should have written it on my sketch.

The engineer firstly TDR tested from the PCP cabinet, with my modem still connected.

After carrying out his work at my home, he TDR tested from my home back to the cabinet, the D-side was still connected at the cabinet (as per the sketch).

These tests were conducted using an 'Exfo' tester.

I THINK a 'Hawk' tester requires an open end or an impulse generator to be attached.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 10, 2012, 11:28:33 AM
@ les 70,

I hope BS will correct me if I'm wrong, but it's my understanding that "ordinary" BT O staff do not have access to FTTC cabinets (Unless they have been issued with the secure key) as I believe any VDSL modifications are only carried out in the associated PCP (or possibly on the associated cable joints if necessary).

Also FTTC cabinets around Guildford (and I believe other earlier version cabinets) have additional star shaped keys rather than the standard triangle ones. Later cabinets have reverted to the triangle ones.
(There's a nice easy overtime job for BS to go round swapping out the star keys !)

Kind regards,
Walter

Ha ha, yes us mere mortals, AKA 'Ordinary BT O staff'  ;) ;D are not allowed in the FTTC Cabinets. Obviously as the 'Build' is taking place we can, as the link cables have to be installed, but after that it's over to the PCR lads (Private Circuit Repair) to maintain. Also, with the presence of 240V power, I believe (but can't confirm) that our Power Maintenace Engineers may be tasked to enter them at times ??

The best form of TDR trace is when it's taken against applied voltage, so the best method would be to TDR back from the premises towards the PCP with all connections intact. The other beneficial test would be to perform a 'Leg balance' test from the PCP to the premises, in other words on a 'dead pair'. With JDSU/EXFO or HAWK we can measure each leg's resistance and capacitance. If there's a +/- 5% difference between legs, I would probably investigate further.

BE, I may be at cross-purposes with you but the HAWK has most of the same functions as the JDSU and EXFO in relation to copper pair testing. The only 'impulse generator' I can think you mean is what's called a 'Remote Unit' that has to be physically connected up at one end of the circuit ?? This is exactly the same for the other 2 testers. These would only be fitted for testing at 300Khz or any other inputted frequency.
Instead , we use a 'Remote Unit Emulation' which is activated by dialling in from our mobiles and mimicks fitting an actual unit. Again, this RUE test (usually used for PQT testing), can be used on all 3 testers. At present, it tests at 1.6Khz then applies an algorithm to calculate the results at 300Khz.

In a nutshell, HAWK/JDSU/EXFO are very very similar when it comes down to Copper pair testing.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 10, 2012, 01:21:02 PM

BE, I may be at cross-purposes with you but the HAWK has most of the same functions as the JDSU and EXFO in relation to copper pair testing. The only 'impulse generator' I can think you mean is what's called a 'Remote Unit' that has to be physically connected up at one end of the circuit ?? This is exactly the same for the other 2 testers. These would only be fitted for testing at 300Khz or any other inputted frequency.
Instead , we use a 'Remote Unit Emulation' which is activated by dialling in from our mobiles and mimicks fitting an actual unit. Again, this RUE test (usually used for PQT testing), can be used on all 3 testers. At present, it tests at 1.6Khz then applies an algorithm to calculate the results at 300Khz.

In a nutshell, HAWK/JDSU/EXFO are very very similar when it comes down to Copper pair testing.  :)

Ah, thanks for clarifying that BS - my misunderstanding.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: les-70 on April 10, 2012, 03:55:26 PM
  I wondered if BS could comment on the realism of the examples in the EXFO application note given above in my first post here?  and also in relation to the "The hump in your sketch look bit like a weak HR point in the cable??." remark I made  based on the EXFO examples

 ps I thought all the FTTC DSLAM cabling for every port in the DSLAM went to the ordinary CAB where it joined the main copper pairs as required.  I am thus not sure why any disconnection would need FTTC access. Sounds like I am wrong?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 10, 2012, 06:02:54 PM
Quote
ps I thought all the FTTC DSLAM cabling for every port in the DSLAM went to the ordinary CAB where it joined the main copper pairs as required.

Correct. The tie-pairs are connected to the DSLAM, within the FTTC, at build time and are run into the supporting PCP, where they are left "hanging" until a service provision require a port.

Quote
I am thus not sure why any disconnection would need FTTC access. Sounds like I am wrong?

It doesn't and you're not!  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on April 10, 2012, 06:51:07 PM
@ les 70,

Just to add that all connections, disconnections and maintenance is normally done by our good BT Openreach friends (even in the middle of winter with the rain hissing down) within the PCP leaving the FTTC alone.
Even if there was a question about the integrity of the inter-cabinet tie cables or the actual DSLAM ports, I suspect the standard solution would be to select a different pair circuit and leave the FTTC completely out of the investigation.
Were that to occur I suspect some DSLAM re-configuration would also be required.

Below is a link to a low res picture of a PCP cabinet I took last summer, during the lunch break, just as the cables were being terminated in the FTTC.
If you carefully count all the wires you will see that the E side (on the LHS) and the D side (RHS) tie cables have 100 twisted pairs in bunches of 10 pairs.
As there are no FTTC connections yet, all the original E to D jumpers are still intact mostly running along the top of the cabinet.

When a new FTTC service is required the corresponding pairs from the same bunch in both tie cables have new jumper pairs crimped and then punched down into the IDC blocks to connect the service to the appropriate E side and D side pairs.
In these parts, this type of IDC cabinet is in a minority with most using the loose pairs construction as illustrated in the second picture link (Before this particular cabinet was re-sleeved to accommodate the tie cables); in which case a new jumper pair is just crimped to the pairs in the bunch at one end and to the appropriate E side and D side pairs at the other. Finally here we also have yet another construction where the tie cables are made off onto new blocks of IDCs with the twin jumper pairs now having punched down connections at both ends. Ergo our long-suffering friends can be confronted with at least three different configurations of connections whether its pitch black or otherwise. What astonishes me is that, with the exception of BE's case, BT O staff get it right first time for the vast majority !

Some of us might have wry smiles when we observe Mr Livingstone saying quite earnestly that BT are investing vast amounts of money in this 20 year solution.

http://www.scribd.com/doc/66247741/BT-IDC-PCP

http://www.scribd.com/doc/42050356/Typical-BT-PCP-Section

Kind regards,
Walter

PS I'm fully expecting (and hope) BS will contribute to my little essay !

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 10, 2012, 06:55:36 PM
  I wondered if BS could comment on the realism of the examples in the EXFO application note given above in my first post here?  and also in relation to the "The hump in your sketch look bit like a weak HR point in the cable??." remark I made  based on the EXFO examples

 ps I thought all the FTTC DSLAM cabling for every port in the DSLAM went to the ordinary CAB where it joined the main copper pairs as required.  I am thus not sure why any disconnection would need FTTC access. Sounds like I am wrong?

Hi les

Yes, I read that linky with interest, and TBH, have saved it as well. 'Tis a good link sir, and I personally can't fault it.

Regarding your other point (the 'hump'), I've already PM'd Mr Bald_Eagle about this, but for clarification it could be a High Resistance (HR) fault developing, or a cable poundage change. As I've mentioned previously, I personally would have TDR'd the circuit whilst still 'juiced up' and measured the distance to the 'hump' on the trace, by way of moving the cursor to its position on the trace screen. It then gives a distance in metres as to how fat this is. I could then cross-reference this measurement against the plant 'Network Records' to ascertain if there is a cable change at approximately this distance. This is a bit 'hit and miss' as the NR's aren't particularly kept up to date as they are stored on our hard-drive and any plant renewal that was carried out, we would be unaware of via these records. Obviously, the NR data-base would be updated with the new details.

What I would also have done whilst the trace was running, is to ring the EU's landline and watch to see if the 'hump' increased in height, a sure-fire sign of a HR fault.

Thanks again for that linky.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 10, 2012, 07:10:01 PM
Hi Walter

Another comprehensive and insightful guide to our FTTC cabinets. Some of you guys should come and work with us, you have the same, and often more knowledge than we do .......  :-[ ;D

As pointed out, we dont enter the actual DSLAM Cab. If there's a port fault that we identify using our testers in the original-sited Cabinet. We then ring our NGA Helpdesk for co-op. This can either be the usual port reset, DLM reset or a 'Lift & Shift'. What I can say is, the timescales involved in performing a VDSL 'L&S', are far in advance of the ADSL 'L&S'. I've been at Cabinets for up to 3 hrs whilst we tried 2 different 'L&S'. The job then had to go back to PCR as it was apparent the DSLAM had gone faulty. Meanwhile back at the ranch, my boss was heating up his 'Poor Performer' branding iron !!! Only jesting, but a few of them a week and it could quite easily become the truth. :lol:

Thanks Walter for the understanding of OR lads and lasses, having to work in all weathers. It's not quite time just yet to get the smallest violin in the world out, and play a sad tune for us. But, cold, wet weather can be a small hindrance when working outside in it. Especially when you lose feeling in your fingers, and you are getting constant electric shocks due to the body resistance being damn near 0 ohms !!!  :'( ;D. Sod it, get that violin out after all !!!! ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on April 10, 2012, 08:51:38 PM
@ BS,

I do really sympathise. Many many moons ago I have done some winter work 30 ft up (and without a hard hat !) with conductors up to about 1 Inch in diamater. You begin to get worried when your legs refuse to go down the ladder !

However I digress. Whilst I realise you are in no position to question the lord high executioner, sooner of probably later, somebody somewhere has to think about raising a white flag regarding FTTC deployments, or at the very least give you, or your office staff, some tools to discover what is going wrong with a DSLAM ! I suspect that a part of that design is in place at a crude level using the telemetry services which are installed in the FTTC. As a tool of last resort there must be a way of rebooting the DSLAM locally. There should also be a watchdog healthy signal transmitted periodically with an alarm attached so your control centre can take appropriate action upon a failure. These should be hard wired through the 5 pr twisted pair cable along with many other more complex functions available through ethernet control messages down the fibre channel.

Let us close this particular conversation as I expect that nobody around has sufficient knowledge yet to discuss these matters properly.


Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 11, 2012, 04:50:47 PM
Just found something interesting, look like we now have the option to disable interleaving, thank god!

Take a look guys - http://www.openreach.co.uk/orpg/home/products/super-fastfibreaccess/fibretothecabinet/fttc/downloads/GEA_FTTC_2%2063350%20111108.pdf
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 11, 2012, 06:58:40 PM
Not sure if I'm missing a trick here Josh ?? That link doesn't mention in as many words about switching off interleaving, it just alludes to the fact you can choose between stability or speed. Is this what you mean ?? :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 11, 2012, 09:33:58 PM
Not sure if I'm missing a trick here Josh ?? That link doesn't mention in as many words about switching off interleaving, it just alludes to the fact you can choose between stability or speed. Is this what you mean ?? :)

Yeah BS,

Standard - Auto, what we are all currently on.

Stable- Interleaving

Fast - Fastpath, lower ping for gamers.

You can now choose one of those options. Unless I'm missing something here?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 12, 2012, 07:23:10 AM
Not sure if I'm missing a trick here Josh ?? That link doesn't mention in as many words about switching off interleaving, it just alludes to the fact you can choose between stability or speed. Is this what you mean ?? :)

Yeah BS,

Standard - Auto, what we are all currently on.

Stable- Interleaving

Fast - Fastpath, lower ping for gamers.

You can now choose one of those options. Unless I'm missing something here?

Thanks Josh. However, the EU has always had personal control of that situation. See ..... https://www.btwholesale.com/shared/document/Products/Broadband/IPStream/dsl_max_myths_legends_issue1.pdf ........ section 12.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: c6em on April 12, 2012, 08:56:05 AM

Not as I understood it on FTTC.
I can recall seeing somwhere on Plusnet forums that the Interleaving is currently always set 'on' on FTTC and not even the ISP's can switch it off.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 12, 2012, 09:30:03 AM

Not as I understood it on FTTC.
I can recall seeing somwhere on Plusnet forums that the Interleaving is currently always set 'on' on FTTC and not even the ISP's can switch it off.

The document linked to was great for ADSL, written in easy to understand layman's terms.

However, some areas require a complete revison for VDSL2/FTTC services, such as DLM actions, BRAS Rate updates, even the use of separate modems/routers has quite an impact.

e.g. a modem re-sync does not always initiate a new PPP session, thus the IP Profile / BRAS Rate can end up stuck at a high or low level, completely unrelated to the modem's sync speed, which really confuses a large number of users as they cannot understand why their throughput appears to have no relationship to the IP Profile as reported by the BT Tester.

More often than not, the ROUTER has to be reset to force a new PPP session that will actually update the BRAS Rate / IP Profile.

Having "found out" quite a bit about VDSL2 & FTTC, mainly by trial & error, we could possibly write a similar document between us.
However, some elements of how FTTC works are apparently "secret" (especially any stats from the supplied locked modems) & the document would not be "official".


Regarding Interleaving, I am with Plusnet & their various reports (& my own logs) confirm that Interleaving can be in various states for DS & US Separately:-

OFF - Interleaving depth of 1
LOW - I have seen DS Interleaving depths of up to 1700 , still classed as LOW, while US was OFF
HIGH - I am not sure what depth signifies the start of HIGH.

Further, I have not seen MEDIUM as an interleaving state but it MIGHT exist, alternatively it may simply swith from LOW to HIGH.

Plusnet have officially confirmed to me that they have no control whatsoever over Interleaving settings for FTTC services as DLM handles it automatically.
Plusnet also confirmed they are unable to request a manual override of Interleaving settings via BT OR.

Currently, Interleaving is completely OFF for my connection (DS & US both at a depth of 1 - from my own logs).

Also this from Plusnet's reports:-

Test Outcome Pass 
Test Outcome Code GTC_FTTC_SERVICE_0000
Description GEA service test completed and no fault found .
Main Fault Location OK
Sync Status In Sync
Downstream Speed 32.2 Mbps
Upstream Speed 5.8 Mbps
Appointment Required N
Fault Report Advised N
Profile Name 20M-40M Downstream, Interleaving Off - 3.6M-7.2M Upstream, Interleaving Off  
Time Stamp 2012-04-08T05:15:00


Some other documents do suggest that Interleaving adjustments CAN be requested for various profiles:-

"Standard - Auto, what we are all currently on.

Stable- Interleaving

Fast - Fastpath, lower ping for gamers."

An official FTTC specific Myths & Legends document from OR would be most helpful for end users.
However, as it might have to give some "secrets" away, I wouldn't hold your breath waiting for its release into the Public Domain.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on April 12, 2012, 10:01:22 AM
@ BE,

VERY well done in beginning "our" document !

You might be interested in the news article I've just posted too !

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 12, 2012, 10:02:35 AM
Interesting BE, thanks for that!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 12, 2012, 02:33:52 PM
Just thought I'd update you on the issues I've been having, as it may be the same case as yours.

Had another Engineer here just 10 minutes ago, he was on the phone to the REIN team and tuned his van radio into the 612KHz frequency, drove around the street with his mobile on loud speaker to the REIN Engineer, and has confirmed there is an issue a few doors down. He has booked him to visit in the next few days. He's coming from Leeds, I'm in Barnsley so it's 30 minutes drive. Anyway he will be coming to track the REIN down and hopefully fix the problems, they can see errors on the line all the time and he said it would explain why I have a high attainable rate on 45Mbps but a lower sync on 28Mbps.

Just thought it would be possible Paul that your in the same situation as me?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 12, 2012, 05:24:55 PM
Hi Josh,

I thought your issues had been resolved by replacing the connection module at 72 m from your master socket, giving you the full fat 40Mb sync speed.

Has it all gone pear shaped again since then?

Please keep us posted regarding the REIN investigations & outcome.
It may well be worth you starting a new thread dedicated to that as a specialised topic.

Cheers,

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 12, 2012, 06:01:57 PM
Hi Josh,

I thought your issues had been resolved by replacing the connection module at 72 m from your master socket, giving you the full fat 40Mb sync speed.

Has it all gone pear shaped again since then?

Please keep us posted regarding the REIN investigations & outcome.
It may well be worth you starting a new thread dedicated to that as a specialised topic.

Cheers,

Paul.

Yeah it's all gone pair shaped again  :(

And I might as well start a few thread, I will keep you updated mate!

Cheers,

Josh
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 12, 2012, 07:23:30 PM

Not as I understood it on FTTC.
I can recall seeing somwhere on Plusnet forums that the Interleaving is currently always set 'on' on FTTC and not even the ISP's can switch it off.

The document linked to was great for ADSL, written in easy to understand layman's terms.

However, some areas require a complete revison for VDSL2/FTTC services, such as DLM actions, BRAS Rate updates, even the use of separate modems/routers has quite an impact.

e.g. a modem re-sync does not always initiate a new PPP session, thus the IP Profile / BRAS Rate can end up stuck at a high or low level, completely unrelated to the modem's sync speed, which really confuses a large number of users as they cannot understand why their throughput appears to have no relationship to the IP Profile as reported by the BT Tester.

More often than not, the ROUTER has to be reset to force a new PPP session that will actually update the BRAS Rate / IP Profile.

Having "found out" quite a bit about VDSL2 & FTTC, mainly by trial & error, we could possibly write a similar document between us.
However, some elements of how FTTC works are apparently "secret" (especially any stats from the supplied locked modems) & the document would not be "official".


Regarding Interleaving, I am with Plusnet & their various reports (& my own logs) confirm that Interleaving can be in various states for DS & US Separately:-

OFF - Interleaving depth of 1
LOW - I have seen DS Interleaving depths of up to 1700 , still classed as LOW, while US was OFF
HIGH - I am not sure what depth signifies the start of HIGH.

Further, I have not seen MEDIUM as an interleaving state but it MIGHT exist, alternatively it may simply swith from LOW to HIGH.

Plusnet have officially confirmed to me that they have no control whatsoever over Interleaving settings for FTTC services as DLM handles it automatically.
Plusnet also confirmed they are unable to request a manual override of Interleaving settings via BT OR.

Currently, Interleaving is completely OFF for my connection (DS & US both at a depth of 1 - from my own logs).

Also this from Plusnet's reports:-

Test Outcome Pass 
Test Outcome Code GTC_FTTC_SERVICE_0000
Description GEA service test completed and no fault found .
Main Fault Location OK
Sync Status In Sync
Downstream Speed 32.2 Mbps
Upstream Speed 5.8 Mbps
Appointment Required N
Fault Report Advised N
Profile Name 20M-40M Downstream, Interleaving Off - 3.6M-7.2M Upstream, Interleaving Off  
Time Stamp 2012-04-08T05:15:00


Some other documents do suggest that Interleaving adjustments CAN be requested for various profiles:-

"Standard - Auto, what we are all currently on.

Stable- Interleaving

Fast - Fastpath, lower ping for gamers."

An official FTTC specific Myths & Legends document from OR would be most helpful for end users.
However, as it might have to give some "secrets" away, I wouldn't hold your breath waiting for its release into the Public Domain.

Thanks for the continued education into FTTC, BE. My simple mind can't see why the same DLM logic on ADSL isn't applied to VDSL, other than for 'Secrecy purposes'. I'm not really one who subscribes to that train of thought, but take the points about the 'locked down' modems. But having a choice about whether to have IL applied or FP, should be a no-brainer, as it is with ADSL !!

From your exceptional post, it's obviously apparent that as a community we really are in the land of learning. There seems to be so many differing thoughts as to what is 'true' and what isn't.

We've had a voice-mail com from one of our senior managers today stating that 97% of Lancs will be Fibred-up by the end of 2014 (I think he said 2014 ?) thanks to the government chucking in a load of dosh, Lancs Council basically have £64 Million in the coffers now. As I've been quite busy I didn't listen intently to the message, but am sure there will be a thousand more communiques to follow on the same subject. Point being, I may just be able to give deeper 'real life' feedback as time progresses. Having said that, by C.O.P. in the year 2014, you'll probably all be VDSL scientists and have moved into trialling shape-shifting. ;) ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 12, 2012, 08:09:49 PM
Thanks for the continued education into FTTC, BE. My simple mind can't see why the same DLM logic on ADSL isn't applied to VDSL, other than for 'Secrecy purposes'. I'm not really one who subscribes to that train of thought, but take the points about the 'locked down' modems. But having a choice about whether to have IL applied or FP, should be a no-brainer, as it is with ADSL !!

The logic is probably very similar. I gather VDSL & VDSL2 is more or less an extension to the ADSL2+ specification.

However, purely from trial & error, it appears that IP Profile rates for FTTC connections are around 96.79%, compared to ADSL2+ at 88.2%.

It also appears that the ADSL 10 day training period is completed in either 1 day or 2 days for FTTC connections (subject to whether serious errors are detected or not).

We don't have any relevant/reliable speed v distance charts for FTTC.

VDSL2 frequencies are much higher than ADSL frequencies, with almost 4000 bit loading tones available as opposed to 216 or 512 tones.

Attenuation plays a much bigger part in the equation as frequency increases, relative to cable lengths from the cabinet.
A 5km ADSL cable length would provide some sort of connection, yet it appears that VDSL2 just cannot achieve any sort of connection over much shorter distances.

etc. etc. etc.


So yes, the logic & principles are probably very similar, but the "average" end user isn't interested in any of that.
They just expect 40Mb or now 80Mb connections (or is that now changed to 38Mb & 76Mb?)


Quote

From your exceptional post, it's obviously apparent that as a community we really are in the land of learning. There seems to be so many differing thoughts as to what is 'true' and what isn't.


So why haven't BT and/or OR released the 'truth', the whole 'truth' & nothing but the 'truth' for geeks like us?
Surely the official release of a document similar to the Myths & Legends document would quell so many rumours, misunderstandings & outright misinformation purpoted to be facts.

Quote
We've had a voice-mail com from one of our senior managers today stating that 97% of Lancs will be Fibred-up by the end of 2014 (I think he said 2014 ?) thanks to the government chucking in a load of dosh, Lancs Council basically have £64 Million in the coffers now. As I've been quite busy I didn't listen intently to the message, but am sure there will be a thousand more communiques to follow on the same subject. Point being, I may just be able to give deeper 'real life' feedback as time progresses. Having said that, by C.O.P. in the year 2014, you'll probably all be VDSL scientists and have moved into trialling shape-shifting. ;) ;D

Good luck with that & here's hoping your are closer to the head than the tail of that queue  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 12, 2012, 08:16:20 PM
Ha ha, BE. Cheers for the closing comment bud. ;D

TBH, regarding a VDSL M&L Doc, I genuinely believe 'they' still don't actually know themselves ?! It's a relatively new product on our shores in relation to pumping it over our last mile of 'string', and I feel as time goes by engineer feedback will be the key to producing the said document. As somebody else commented on another thread (Iunless it was on this ??  :-[), laboratory condition testing is a world away from real-life, so I think its a case of waiting and watching BE.

Cheers.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Blackeagle on April 12, 2012, 08:50:05 PM

It also appears that the ADSL 10 day training period is completed in either 1 day or 2 days for FTTC connections (subject to whether serious errors are detected or not).

We don't have any relevant/reliable speed v distance charts for FTTC.


My engineer told me that DLM would be active as soon as his JDSU got showtime for the first time.  He said it would have figured out the MSR 24hrs later.

With regard to distances, there is a chart here http://www.thinkbroadband.com/news/5161-how-fast-will-fttc-run-at.html (http://www.thinkbroadband.com/news/5161-how-fast-will-fttc-run-at.html)  As I reckon my line is approx 650m, that fits bang on the chart with my estimate of 33Mbps download.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 15, 2012, 10:01:09 AM
Update 15/04/2012:

Following the engineer's visit of Staurday 7th, apart from DLM making a couple of adjustments within the first 2 days, my connection enjoyed a period of stability.

Sync speed was around 32Mb.

SNRM rose & fell with daytime & nighttime, peaking at a slightly lower than expected 4.5dB.

Attainable rates remained steady at around 30Mb (probably a little low due to SNRM being below 6dB).

Use of the phone only lowered SNRM by 0.1db / 0.2dB.

Output Power levels stopped fluctuating.

Various error counts diminished & some remained at zero as Interleaving, INP & delay are still switched OFF.

Error Seconds still seem rather high. Increase in Error Seconds appeared to coincide with my entry onto Plusnet's 80/20 trials. As 80/20 is a complete waste of time for my connection, I have requested to be switched back to the 40 Mb service, which should happen early next week.

All in all, it really appeared that last week's engineer had completely fixed the use of the phone causing disconnections and large drops in SNRM issue.


However - there's always a however when discussing my connection - the issue appears to have resurfaced since Thursday & my connection has suffered a few re-syncs.

It is currently in snc at only 23401 k, with SNRM at 9.9dB.
Over the last couple of days, SNRM has alternated between decreasing & increasing whenever the phone is used (incoming and outgoing calls).

The re-syncs appear to have occured when SNRM tails off over a 3 or 4 minute period, a couple of times into negative values.
I have now added up to minus 5dB in the SNRM graph's Y axis.

A couple of re-syncs aren't displayed due to the scales of the graphs & the fact that the re-sync speed had only changed by a few k.

What causes the reduction in SNRM at various times of day/night, now that it is not only when the phone is used, I have no idea.
My logs don't show a sudden increase in errors to really high values (my connection has previously hung on with error bursts of 200,000 or so).

It all sounds more like a physical (still intermittent) line fault to me.

Any suggestions anyone?

Could it actually be something within the Fibre cabinet itself?


I am mindful of the as yet unknown cause of the "underlying" issue as mentioned following the engineer's discussion with OMC (Fibre centre) along with the hump in the TDR trace.

I have very recently taken to driving around with the car radio tuned to 612KHz (proper saddo) & do notice a couple of areas between home & the cabinet where the background white noise changes to a buzzing sound (during daytime).
At nighttime, the high strength of some Spanish radio station appears to block all that out at 612 KHz.

Not that it's relevant to my connection, I notice the same buzzing sound when passing through some (not all) Pelican crossings & normal traffic lights.

@BS, is that the sort of hard to describe sound?

The phone is still plugged into the test socket via a dangly filter, with all the other internal wiring completely disconnected.

The switch back to a capped 40Mb service may just have some impact, although on the 80/20 trials I did see a few days of stability, so probably not.
At least DLM won't be attempting to send anything at all to me at the highest (& most susceptible to interference) frequencies that come with the up to 80 Mb speeds.

This current disapponting position has been reported to Plusnet.

The latest 8 day's graphs are attached for reference.


Cheers,


Paul.


Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 15, 2012, 10:41:26 AM
Got a few questions BE, I'm wanting to use the graphs but I have no idea how to do so. I have installed them so there not in C: Drive but what do I do now? Do I need to plug a second lan port into you router? and how do I set this up on the modem?

Thanks mate.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 15, 2012, 11:09:25 AM

Got a few questions BE, I'm wanting to use the graphs but I have no idea how to do so. I have installed them so there not in C: Drive but what do I do now? Do I need to plug a second lan port into you router? and how do I set this up on the modem?


My setup is as follows:-

Netgear WNR1000 v 3 Router, IP Address 192.168.1.254

Modem settings unchanged (apart from being unlocked), 192.168.1.1

All PCs currently connected to the router (wireless & ethernet) automatically obtain an IP Address.

Router WAN port connected to Modem LAN1 port

Spare Router port connected to modem LAN2 port.

both normal Internet access & access to the modem's stats & therefore graphing scripts are available at the same time.

The graphing scripts default to using the modem's default IP Address of 192.168.1.1
If you have changed that for any reason (some people do), the scripts will need to be edited to reflect the modem's new IP Address (search & replace is quick enough).


The script instructions that were included in the download zip file explain how to use the scripts & optionally set up Windows Task Scheduler for every minute 24/7 logging (until stopped).


Depending on your particular router, this post MIGHT be of some help:-

http://forum.kitz.co.uk/index.php/topic,10968.msg214960.html#msg214960

HTH,


Paul.


EDIT:

I would just add that the scripts do NOT work with file and folder names with spaces in them.


Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 15, 2012, 12:45:42 PM
Thanks a lot mate, going to get it set up now.  :)

Edit: No stats are showing in current or ongoing folders?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Blackeagle on April 15, 2012, 02:22:15 PM
Run one of the graph scripts Josh.  I fell into this as well, thinking that the graphs would be auto-produced but they aren't.  Just the log file is. Run teststats2.bat, graphpd.bat and graph6.bat and you should get all the required stuff  ;)

Props to those that produced the scripts.  Currently I am working on a .net prog to do the same/similar thing.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on April 15, 2012, 03:10:26 PM
Paul, could you please take a look at my line stats on my topic.

Thanks,

Josh
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on April 15, 2012, 03:24:03 PM
@ Paul,

Picking up on your earlier question on anything within the FTTC here are a few ideas:-

A.  Isolate the E side pair within the PCP and observe if that makes any noticeable difference.

B.  I suspect nobody has even opened the FTTC as BT O faults staff do not have access there. Whilst it's usually impossible to ask for a specific action perhaps PlusNet can prevail upon BT O et al ? E.g. with tone generator at your test socket, trace your pair within the FTTC, then 1. do a detailed close inspection & check of the pairs and the relevant Telco64 plug reseating if practical 2. Then re-punch down the IDC wires 3. Reconnect the modem and test.

C.  Remake all the crimps / IDC connections within the PCP and observe.

D.  Do a PCP Lift & Shift.

Kind regards,
Walter
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on April 15, 2012, 05:13:01 PM
I'm sorry to see your still without a resolution Paul, have there been any discussions about the port possibly being faulty?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 15, 2012, 05:37:22 PM
Well, my connection re-synced yet again this morning.
This time, sync speed was increased to 27396 k.
SNRM is currently at 8.3dB & the attainble rate is 30700 k.

I can't understand why, especially for my connection, Interleaving is still completely OFF.

Again, I can see nothing in my logs to suggest a reason for this latest re-sync.

Over the months, I have had a port flex, a lift & shift, copper pairs swapped, the E-side disconnected & the D-side tested, my drop wire replaced etc.

As far as I am aware, no repair work whatsoever has been carried out (or anything even checked) within the fibre cabinet itself.

I am only a now confirmed 834m from the cabinet.

I could almost accept permanent low(ish) speeds over that line length, but not the instability which just HAS to be a really easy fix (once someone can actually pinpoint it), doesn't it?.

I genuinely thought last weekend's engineering work had more or less resolved everything.

Unfortunately, it appears the saga will have to continue, hopefully not for too much longer.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 15, 2012, 08:03:40 PM
Quote
I could almost accept permanent low(ish) speeds over that line length, but not the instability which just HAS to be a really easy fix (once someone can actually pinpoint it), doesn't it?.

b*cat nods, with an sad look on his face.  :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 16, 2012, 07:51:41 AM
Update 16/04/12:

It looks as though my service has now been switched back to 40Mb/10Mb.

At least, following another early hours connection re-sync, my Upstream IP Profile has reverted to 10Mb rather than the 20Mb reported whilst on the 80/20 trial.

However, simply picking up the phone a few times this morning to run the 17070 Quiet Line Test caused SNRM to drop below zero with immediade connection re-syncs.

Dialling in once also caused SNRM to drop below zero with an immediate re-sync.

Since dialling in, I can again use the phone without the connection actually dropping.
SNRM still drops by 2dB to 4dB or so though.

I wonder, could the ringing pulse voltages/current have effected yet another temporary "repair" on possibly a dodgy cable joint somewhere?

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 16, 2012, 10:49:32 AM
"I have very recently taken to driving around with the car radio tuned to 612KHz (proper saddo) & do notice a couple of areas between home & the cabinet where the background white noise changes to a buzzing sound (during daytime).
At nighttime, the high strength of some Spanish radio station appears to block all that out at 612 KHz.

Not that it's relevant to my connection, I notice the same buzzing sound when passing through some (not all) Pelican crossings & normal traffic lights.

@BS, is that the sort of hard to describe sound?"


Obviously, without listening to the actual noise myself, I couldn't say for 100%, but I would punt that it is REIN that you are hearing. LOL at the Spanish radio-station. It's painful when that is transmitting. ;D

I remember when on our REIN course, that the instructor had a 'sound-byte' of the noise, but try as I might I cannot locate it anywhere in the archives that I have access to. He had a piece of kit that was found culpable of REIN (it was a Hub power adaptor), and with the official Tester 444B switched on (Glorified radio), he plugged it in for about 0.0004 of a second to demo the noise in a 'live' situation. If he'd left it in for a 'period of time', it would have caused havoc with the DSL equipment in the Exchange.

I'll continue on my quest to fing the recorded soundbyte, but I've a feeling Walter or B*Cat will find a similar one before me !!  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 16, 2012, 01:12:33 PM
Cheers BS,

Could this have any significance from my other message?:-

Quote

I wonder, could the ringing pulse voltages/current have effected yet another temporary "repair" on possibly a dodgy cable joint somewhere?

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: snadge on April 16, 2012, 01:17:43 PM
wow - ive not read the entire thread for obvious reasons, but Iam subbing to it so i can see if you get sorted mate... I recently had a problem similar , dropouts on incoming calls, fiddling about with wires and filters seemed to fix it until later on started again - for me they said it was crossed wire as we had random rings and could hear people talking, still waiting for it too be fixed hopefully tomoz.

Your in good hands anyway - so do you think its REIN thats the cause? how can this happen when the phone rings if its REIN (RP, anyone?)..?

anyway, best of luck mate..
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 16, 2012, 01:37:20 PM
Cheers BS,

Could this have any significance from my other message?:-

Quote

I wonder, could the ringing pulse voltages/current have effected yet another temporary "repair" on possibly a dodgy cable joint somewhere?


If i'm understanding your question correctly, BE. I've never known ringing voltages/current temporarily 'cure' a 'HR'. If anything, it highlights the issue in the form of audible noise when using the PSTN part of the circuit.

A trick 'we' use when trying to locate a persistent (multiple reports) 'HR-type fault', is to 'Megger' the line, obviously with all Exchange and EU's equipment unplugged. This can 'blow' the fault to a full 'Open circuit'. It has in the past, also been used to dry out a wet circuit. For example if there was minimal fault voltages present, and the fault was in a cable-length (IE-not in an actual cable joint), then a quick blast from the 'Megger' would put paid to this. This was only a temporary measure as over the months 'damp ingress' would most likely re-occur.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 16, 2012, 06:49:34 PM
Quote
I've never known ringing voltages/current temporarily 'cure' a 'HR'.

A joint that has corroded in such a way as to become semiconducting can be temporarily "fixed" by subjecting it to AC voltages, higher than the normal DC "bias" voltage.  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 16, 2012, 07:19:01 PM
Quote
I've never known ringing voltages/current temporarily 'cure' a 'HR'.

A joint that has corroded in such a way as to become semiconducting can be temporarily "fixed" by subjecting it to AC voltages, higher than the normal DC "bias" voltage.  ;)

I can only say it as I see it, B*Cat. We tend to use the ringing voltage (AC wave) to enhance the 'HR', rather than to temporarily cure it ?

It's a common'ish occurence, whereby the EU has had a fault raised for a 'LTOK but noisy' issue. We arrive on-site and Sods Law dictates it will be noise-free. However, a burst of 'ringer' and a high-percentage of the time the noise will re-appear. Granted, not in all cases, but often.

That's why in these instances, we also use the TDR trace measuring back against applied voltage, then ring the faulty landline. The 'peak' will be more prevalent under this state, than against nominal working voltage (-48 or -54 Vdc).

As I say, I've only got my experience to comment on, I've nothing technical to back-up my claims.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 16, 2012, 07:44:01 PM
I will perform one of my best Japanese style bows to your experience, BS.  :)

Please take another look at the first 13 words of my previous post --

Quote
A joint that has corroded in such a way as to become semiconducting . . .

Now you will see that I used the word semiconducting, not the abbreviation HR.

If you were allowed contact with the various wizards within your employer's Grimbledon Down (a.k.a. Martlesham Heath), I'm sure they could give you practical evidence of such an occurrence. Somewhere in the back of my mind I have a recollection that a reverse-biased diode can be used as a form of a white-noise source. Perhaps an electronic engineer could comment, please?

B*Sheep --->  :friends:  <--- B*Cat

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 16, 2012, 08:25:34 PM
I will perform one of my best Japanese style bows to your experience, BS.  :)

Please take another look at the first 13 words of my previous post --

Quote
A joint that has corroded in such a way as to become semiconducting . . .

Now you will see that I used the word semiconducting, not the abbreviation HR.

If you were allowed contact with the various wizards within your employer's Grimbledon Down (a.k.a. Martlesham Heath), I'm sure they could give you practical evidence of such an occurrence. Somewhere in the back of my mind I have a recollection that a reverse-biased diode can be used as a form of a white-noise source. Perhaps an electronic engineer could comment, please?

B*Sheep --->  :friends:  <--- B*Cat

I did realise you'd written 'semiconducting', but thought you'd meant it in relation to a 'HR' as BE was pertaining to the small 'HR lump' on the engineers TDR trace ?? :-[

The only time I would liken something as being semi-conducting is when we come across 'Rectified loop' faults. This (for those who aren't aware), is when voltage is allowed to flow in one direction, but not the other. With a meter connected, it would show a 'Loop' condition with the leads connected one way, then an 'Open' condition when the leads are reversed.

This is obviously acting like a diode, which is a semi-conductor with doping-bias applied. I genuinely have never heard of any other instances reffered to as being akin to a semiconductor ?? But as always, your knowledge is far-reaching B*Cat, and I always listen to what you have to say and would love to have a more in-depth insight into what you say.

PS .......  :friends: always mate. ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 16, 2012, 08:38:31 PM
The perils of attempting to interpret another persons experimental evidence, remotely, is fraught with difficulty.  ;D

All we can definitely say is that there appears to be some form of abnormality present in the D-side, which has shown up in that Exfo's TDR trace.

 :drink:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Blackeagle on April 16, 2012, 08:58:13 PM



If you were allowed contact with the various wizards within your employer's Grimbledon Down (a.k.a. Martlesham Heath), I'm sure they could give you practical evidence of such an occurrence. Somewhere in the back of my mind I have a recollection that a reverse-biased diode can be used as a form of a white-noise source. Perhaps an electronic engineer could comment, please?


Yes, you can reverse bias a Zener diode to get it operating in "junction-breakdown" mode and then amplify the white noise produced on the anode.  This would give you several hundred MHZ of white noise.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 16, 2012, 10:01:49 PM
If you were allowed contact with the various wizards within your employer's Grimbledon Down (a.k.a. Martlesham Heath), I'm sure they could give you practical evidence of such an occurrence. Somewhere in the back of my mind I have a recollection that a reverse-biased diode can be used as a form of a white-noise source. Perhaps an electronic engineer could comment, please?

Yes, you can reverse bias a Zener diode to get it operating in "junction-breakdown" mode and then amplify the white noise produced on the anode.  This would give you several hundred MHZ of white noise.

Excellent! Thanks for the confirmation. :thumbs:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on April 16, 2012, 10:19:55 PM
Thanks for the info guys, how could a corroded joint be akin to a reverse-biased zener diode ?? Genuine question.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on April 16, 2012, 11:46:35 PM
I do know that some of the earliest rectifiers were based on sandwiches of copper and copper oxide.

One only needs to have two different metals / metalloids in contact to create a semi-conducting materiel (or a voltaic cell).

The physics / chemistry / materials science / what-not is way outside my area of expertise . . .

All I can say is that, in theory, all manky-joints should be remade, as a matter of course, to eliminate any potential for "mischief".   
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 20, 2012, 07:51:03 AM
Update 20/04/12:


I am still awaiting Plusnet to contact me since reporting 5 re-syncs in a row, simply from using the phone on Monday 16th (4 from dialling out & 1 from receiving a call).

Therefore no engineer visit has been arranged & I am not aware of any work being carried out on my connection that did not require a home visit.


Would you believe it? Just look at a couple of graphs showing the latest 3 days connection:-

(http://i1255.photobucket.com/albums/hh629/Bald_Eagle1/snrm-3_DAYS.png)


(http://i1255.photobucket.com/albums/hh629/Bald_Eagle1/sync-3_DAYS.png)

You can see on the R/H side that I was so confident with the stability that I rebooted the modem this morning to achieve a higher sync speed (now 31244 k).


The connection appears to have stabilised IMMEDIATELY after receiving the incoming call.
Hence my earlier query about ringing voltages creating temporary fixes.

I am also back on a 40Mb/10Mb max profile (by request) following the 80/20 trials.

I think the switch back is purely coincidental as the phone calls causing the re-syncs occured AFTER the switch back.


Compare the 3 day graphs shown above with these - from the latest 8 days.
The immediate difference since that incoming call can be clearly seen:-

(http://i1255.photobucket.com/albums/hh629/Bald_Eagle1/snrm-8_DAYS.png)

(http://i1255.photobucket.com/albums/hh629/Bald_Eagle1/sync-8_DAYS.png)


Due to the scale/resolution of the graphs, the 5 re-syncs cannot be seen clearly, but I could separate the period around 07:00 to show them as evidence & my modem log has also recorded them.



The phone issue & general stability appear to have gradually improved since Monday.
I can now use the phone with hardly any drop in SNRM being seen.

Is it pure coincidence that the weather has been wetter & colder since Monday?


In a way I am slightly disappointed with this stability as I am sure it has only prolonged the inevitable return to instability & lower speeds.

If an engineer turned up right now, no doubt all his tests would return LTOK results.

I wonder if any return to instability will coincide with weather changes i.e. (hopefully) improving as we head toward summer?

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Blackeagle on April 20, 2012, 10:08:39 PM
Hi BE,

I'm glad your line is looking stable at the moment, but I'm slightly confused by
Quote
The phone issue & general stability appear to have gradually improved since Monday.
I can now use the phone with hardly any drop in SNRM being seen.

Is it pure coincidence that the weather has been wetter & colder since Monday?

In my (limited) experience, water is generally a bad thing, although having said that, it is an excellent conductor, but this is usually why its a bad thing !!  Heat I can see.  An expanding joint somewhere could be making a bad contact, causing large fluctuations and introducing noise.  When cold the joint could contract and make a better connection.  Could be tough to track down Paul  :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on April 20, 2012, 10:50:52 PM
Cheers BE,

I didn't really pay that much attention to the weather previously.

Like you, I had it in my mind that water in cables & joints was an especially bad thing, but looking back over a few months worth of various graphs, the connection has looked a little "better" during the colder & wetter winter period.

I only really started to consider weather conditions as a "potential" factor when we recently experienced unexpectedly warm, dry & sunny weather.

It was during those spells that my connection appeared to suffer the most.

It could be pure coincidence though as I have occasionally experienced a few continuous days of stability over the months, with no real explanation as to why it suddenly deteriorates from one day to the next.

The biggest problem in trying to rectify matters is probably that more often than not the connection has "fixed" itself before an engineer visit can be arranged.

The graphs are good at showing the results of an issue, but are not too easy to use in determining the root cause.
e.g. use of the phone. Why would it lower SNRM & then drop the connection for a few days on the trot, apparently fix itself & then start dropping the connection again after a fews of stability (That was prior to the latest engineer's visit).
These events can be clearly seen in the graphs.

The engineer rejumpered the cabinet connections & conducted a few tests & everything seemed more or less perfect.
That only lasted for a few days & then the phone issue started again.

Things now look quite stable again, but no other work has been carried out.
Plusnet contacted me earlier today & there was no mention of arranging an engineer visit.
While my connection is behaving, there probably would be no point though.

If/when this particular issue rears its head again, it would be really useful to conduct line tests (TDR etc.) at the time.
It may then be possible to pinpoint the cause & effect a permanent remedy once & for all.

It would also be incredibly useful to have records of before, during & after tests for comparison purposes.
I'll have to see what can be done about that.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Maturecheese on May 13, 2012, 12:47:12 PM
I haven't read through the thread but in answer to the title  I live around 800 meters cable length from the cabinet and I was syncing at 38 mb I P Profile for the last three months until a recent ongoing fault.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 21, 2012, 09:17:29 PM
Hi Maturecheese,

I haven't read through the thread but in answer to the title  I live around 800 meters cable length from the cabinet and I was syncing at 38 mb I P Profile for the last three months until a recent ongoing fault.


It seems like I had missed your message, sorry.

Has the fault been rectified & if so, what was the diagnosis of the fault?

Paul.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 21, 2012, 09:40:41 PM
Quick Update: 21/05/012

Now that the weather has improved, it appears that another engineer visit is being arranged for Friday 25th (subject to staying warm & dry through this week.

My connection has been reasonably stable for a few days (cold & wettish weather), with using the phone not having any effect other than to lower DS SNRM by 0.1dB or 0.2dB.

Coinciding with the weather's improvement & gaining pace since last night, my DS SNRM level has quite gradually lowered to currently only 2.4dB & use of the phone now causes DS SNRM to drop to as low as 0.8dB.

The above doesn't really make much sense, as it usually wet cables that cause problems.
However, I have noticed this phenomenon on the rare occasions that the weather has been unseasonably warm & dry over the last few months.

I may try to conduct a copuple of tests of my own before Friday's visit if this issue does indeed persist.

FWIW, recent graphs attached.
I also notice a massive & prolonged increase in RSCorr errors, again commencing last night.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on May 23, 2012, 03:54:32 PM
Good luck mate,

I'm reverting back to the 40M profile shortly, the 80M profile has had a negative effect on my line so it's for the best.

Being on the 80M profile has also stopped OpenReach from doing a lift and shift so that's the thing that will be done next.

Hope it all goes well anyway, and do wish they finally find out the cause of your issues.

All the best,

Josh
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 23, 2012, 04:06:30 PM
Update to my message of 21st May:

Fingers crossed for Friday's engineer visit (now confirmed).

Recent stats since my last message are attached, showing the difference a bit of sunshine makes.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 23, 2012, 04:13:44 PM

I'm reverting back to the 40M profile shortly, the 80M profile has had a negative effect on my line so it's for the best.

Being on the 80M profile has also stopped OpenReach from doing a lift and shift so that's the thing that will be done next.



Cheers Josh, & good luck for your L & S.

40Mb & stability have to be better than "up to 80Mb", but achieving nowhere near it combined with instability.

Has your REIN issue ever been sorted?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on May 23, 2012, 04:57:18 PM

I'm reverting back to the 40M profile shortly, the 80M profile has had a negative effect on my line so it's for the best.

Being on the 80M profile has also stopped OpenReach from doing a lift and shift so that's the thing that will be done next.



Cheers Josh, & good luck for your L & S.

40Mb & stability have to be better than "up to 80Mb", but achieving nowhere near it combined with instability.

Has your REIN issue ever been sorted?

Since moving to 80Mb profile I have seen a little more errors on the line, I guess it's to do with the higher frequency's.

And I did have a REIN Engineer come out, he found nothing external but that was too early afternoon to track anything to be honest.

He found the power supply for the modem was giving off some interference so that got replaced.

If the connection is still poor after the L&S, I guess they'll be sending out another one out to try track something down.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 25, 2012, 07:12:29 AM
Just for reference, the latest 24 hours SNRM graph is attached.

I am hoping today's engineer will phone my mobile No. & not the land line & that he will visit my home before disconnecting any cabling at the cabinet etc.

He would then hopefully see the problem for himself & maybe even hear the crackling that has only very recently been heard when conducting quiet line tests.

Disconnecting & reconnecting equipment does seem to effect a temporary cure, thus making any diagnosis very difficult.

Throughout the last few weeks of "issues", the phone has been amazingly quiet.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 25, 2012, 12:44:05 PM
While I have been sat around, twiddling my thumbs, waiting for the engineer to arrive for this MORNING'S appointment (only 16 minutes to go before the engineer ends up being late), I thought I would share a graph of the latest 8 hours SNRM levels with you.

I have intentionally not picked the phone up at all today, yet the connection has re-synced a few times, currently at only 12265k.

Today has been the hottest day of the year so far & my current issue is particularly focused on dry & warm weather.
I really do hope the engineer shows otherwise someone will be finding out that I'm not a particularly happy chappy.



Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 25, 2012, 01:54:19 PM
Well, that's another [censored] day off work wasted.

Apparently, OR cancelled today's appointment (specially arranged to coincide with weather forecasts) 2 hours after it was confirmed Tuesday 22nd May.

I have spoken with Alex over the phone today, expressing my "annoyance" that nobody confirmed the cancellation with me.

Alex was unable (or unwilling) to confirm why the appointment was cancelled.

He did say he would try to arrange another appointment for tomorrow.

To say I am now well & truly [censored] off with the whole bunch of [censored] is a massive understatement.

[censored] ups & breweries come to mind.

The strange thing is, if I missed an engineer's appointment I would be charged for it.
Who the [censored] stands the cost of all the time I have lost from work over these months - ME!  >:( >:( >:( >:( >:( >:( >:(

My connection even re-synced at 13:26 after a load of crackling while I was on the phone to Plusnet.

Of course though, as Plusnet's systems don't see these quick "on the fly" re-syncs, there is only my word & my graphs as evidence.

If we didn't have the graphs, there would be no proof of a [censored] connection at all.

Don't anyone try to tell me this secrecy is NOT intentionally geared to con the users who pay for this [censored].

BTW, the phone was lovely & quiet immediately following the re-sync.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: waltergmw on May 25, 2012, 02:18:49 PM
@ Paul,

It really is getting beyond a joke now. Cold comfort, but you will see in the comment that you are not alone with quite preposterous amounts of time wasted by the paying customers.

http://b4rn.org.uk/bbcs-the-one-show-b4rn-feature
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: eliw on May 25, 2012, 05:02:58 PM
Isnt there something you can do legally to force them to fix this once and for all ? Surely a letter to ofcom may trigger a complete rewiring of your line no matter what it costs. You should maybe consider going down this path.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on May 26, 2012, 12:28:16 AM
By now, I would be considering sending a written letter of complaint (after taking a number of days to compose and edit it), by Royal Mail Recorded Delivery, with a complete log of events, copies of graphs, details of non-appearance of engineers, plus my invoice for time wasted per incident (£150-00 each) to the CEO of the BT Group, a.k.a. The Big Cheese, Ian Livingston (http://en.wikipedia.org/wiki/Ian_Livingston) at the Evil Empire's registered office [1].

[1] "BT Group's . . . registered office is the BT Centre, a 10-storey office building at 81 Newgate Street in the City of London (https://maps.google.co.uk/maps?oe=utf-8&client=firefox-a&q=81+Newgate+Street,+London&ie=UTF-8&hq=&hnear=0x48761b54ca13f181:0x17c025cd0bc5b092,81+Newgate+St,+London+EC1A+7AJ&gl=uk&ei=2hXAT5PSO8mL8gOC8fXtCg&oi=geocode_result&ved=0CAoQ8gEwAA), opposite St. Paul's tube station." Source: Wikipedia (http://en.wikipedia.org/wiki/BT_Group).
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: snadge on May 26, 2012, 10:33:53 AM
joining this for updates..

sorry about your mess BA - I can at least share your pain haha...

good luck
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 26, 2012, 10:52:07 AM
Guess who is REALLY in the doghouse for "forgetting" his wedding anniversary due to all the pent up anger & stress caused by "others" -

ESPECIALLY THOSE WHO DON'T BOTHER TELLING USERS WHO LOSE A DAY'S PAY OR ANNUAL LEAVE THAT SPECIALLY ARRANGED ENGINEER APPOINTMENTS HAVE BEEN CANCELLED - & NOT FOR THE FIRST [censored] TIME EITHER!!

A written apology & some compensation from those who that cap fits may go some way to avoiding the stress to be now caused via probable divorce procedings.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: snadge on May 26, 2012, 10:54:01 AM
ouch!!

sorry to hear about that....
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: renluop on May 26, 2012, 02:30:46 PM
An eagle in a dog house, that's something to let the imagination loose on. :-\ >:D ;D :P :D

Could end up with a furred eagle or a bald dog.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on May 26, 2012, 09:22:07 PM
Update 26/05/2012:

Nobody contacted me from Plusnet, either yesterday afternoon or this morning to confirm whether an engineer had been arranged for today or not.

I was therefore slightly surprised that an engineer (Liam) contacted me this afternoon confirming he was on his way.

Anyway, Liam hadn't been provided any background detals so on his arrival, I outlined the various issues, tests & repair works carried out to date.

Even though the filtered VDSL2 Service Specific FacePlate was only replaced in April, I had very recently retested my connection again with a telephone & the HG612 modem plugged into a dangly filter which was plugged into the master socket's test socket (filtered SSFP completely removed).

Left overnight, SNRM levels remained very stable, as did Output Power levels & various error counts were very low.
More importantly, I was again able to use the phone during the currently hot weather without it causing the connection to drop.

Liam firstly replaced the SSFP, mentioning that he had replaced quite a few as they are apparently prone to failing.
Quite often these faulty SSFPs cause a direct short circuit, completely disabling telephone & FTTC services.

After discussing the problem from February when engineers not working on my connection had caused disconnections while working at the top of the pole where my DP is located, Liam decided to check the connection/cabling at the DP itself.

A new undergound cable was installed from the nearby joint chamber to another DP on the same pole in February when those engineers were unable to provide any further services from the existing DPs.

Liam stated that if today's works didn't fix things, he would consider connecting me to this new UG cable (around 40m in total length). If necessary, that would have to be at another time though as he wasn't allowed to access joint chambers on his own.

While Liam was at the top of the pole, but before starting work, I noticed a brief disconnection of no longer than maybe 30 seconds or so duration.
My modem log has subsequently confirmed it as 27 seconds.

Liam spent a while at the top of the pole checking things & a longer disconnection was noticed.

On returning, Liam confirmed he had only intentionally disconnected once & the fact that when he did disconnect, the end of the old underground feed cable simply snapped off.
He stripped it right back & remade the connection to the DP (screwed not push fit).
That explained the 27 second unintentional disconnection and the unintended disconnections caused by the other engineers back in February.
According to Liam, that DP connection must have been only just serviceable for a long time.

On completion of his repair work Liam requested a DLM reset as my connection had been stuck at a maximum sync speed of of only 19999k for a few days.

This is tonight's result of this afternoon's DLM reset which seems to be holding its own (so far):-

(http://www.speedtest.net/result/1973425318.png)

Error counts are starting to build, but at a much slower rate than of late & they are no longer occuring in massive bursts of thousands/millions of errors within a one minute data sampling period.

All the internal extension wiring was reconnected & I am again able to use the telephone with only small drops in SNRM (0.3db) & without it causing a disconnection.

All in all, today's visit appears to have been successful.
However, this has also appeared to be the case from previous visits, unfortunately only lasting for a few days at a time.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on June 02, 2012, 09:39:00 AM
Hows the connection holding Paul?

Mine is disappointing, currently syncing at 24Mbps.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on June 02, 2012, 10:06:22 AM
Hows the connection holding Paul?

Mine is disappointing, currently syncing at 24Mbps.

Sorry to hear that Josh.


Mine's quite stable now (sync speed has dropped quite a bit though to 28.5Mb).

There have been just a couple of resyncs, to adjust interleaving depths & a couple of forced reboots since the engineer's visit.
There are no longer any problems from using the phone now.


US Attenuation since 2 days before the engineer's visit is bothering me.
It coincided with a change in DS band plan tones from 3939 tones to 3959 tones.

The US band plan where attenuation has increased a lot is outside what my connection can use anyway, so should not have had any effect, but it seems to have done so in lowering both DS & US attainable rates & sync speeds.

My attainable rate & sync speeds were higher than 35Mb when DLM was reset in March.
Attainable rate is currently 33.5Mb.

I'll keep an eye on it for a while before I ask Plusnet to have a look into matters again. 

(http://www.speedtest.net/result/1985474347.png)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on June 03, 2012, 09:06:37 AM
UPDATE 03/06/2012:

Following on from my previous message & 8 days since the engineer's visit, my connection has remained stable.

Looking at snapshot graphs, it is now more or less back to how it was in November 2011.

As mentioned before US attenuation shot up very recently & DS attenuation has increased by around 1dB.

Maybe the DS increase is simply due to the effect of warmer external temperatures on copper/ally cabling.
Temperature certainly affected the filtered SSFP that was O.K.(ish) in cool & wet weather & useless in warm & dry weather.

It is only a small increase, but at the speeds/frequencies involved, does appear to have a few Mb effect on sync speeds.

I suppose 26.5Mb throughput isn't too bad, but it is nowhere near the "up to" 40Mb service & is still 7Mb less than the "up to" 33.5 Mb throughput that I achieved at first.

The changes in band plan profiles from 8c to 17a & more recently a slight increase in available DS tones appear to have negatively affected my connection i.e. as these changes have been at slightly higher frequencies, my attenuation appears to have increased & therefore sync speeds decreased with each change.

My best sync speeds appear to have been on the old 8c profile where everything "up to" 40Mb was crammed into far fewer tones.

This is most unusual, as most other sub-40Mb users saw an increase in DS sync speeds with a slight decrease in US sync speeds.
It may indicate that my physical line conditions deteriorated immediately following the 4 day loss of service last July & have remained more highly attenuated than when FTTC was first installed.

That is my very strong suspicion as the connection did appear pretty near perfect until that point.

Unfortunately, as we are painfully aware, BT in their wisdom, intentionally hid all statstics from users by providing completely locked modems.
So, I have no early stats to compare against my current stats. How useful would that have been in either proving "fault" confditions or making me accept that my connection is & has been just what it is - SLOW DUE TO GENUINE DISTANCE FROM THE CABINET & not slow due to the original & COMPLETELY UNREALISTIC 14.6Mb estimated speed, which BTW is now 30Mb.

21 days to go to the first anniversary of my FTTC installation.
Will it be a celebration? :-\


EDIT:

Noise levels appear to have also increased, particularly at the higher frequencies.
This again could be due to physically higher attenuation/weaker signal to noise ratio or possibly increased cross-talk due to more users being connected.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on June 08, 2012, 09:05:24 PM
Just for fun, here's 190 days worth of my connection stats

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Greybeard33 on June 08, 2012, 10:40:04 PM
Paul,

Having now found time to set up your excellent scripts, I have attached one(!) day's stats harvested from my modem for comparison. My line is probably longer than yours (I am about 1000m by road from the cabinet), yet consistently manages max attainable rates above 40Mb. I do recall that, a few months before the original rollout of ADSL broadband, BT carried out a major refurbishment of the infrastructure in our area, replacing all of the dropwires, many of the wooden poles and at least some of the underground cables. I suspect that, as a result, I may have an all-copper circuit. My attenuation figures appear to be significantly better than yours, even after all the remedial work on your line.

Interestingly, the re-sync at 23:34 on the 6th was triggered by me manually saving the modem log file from the web interface (the last entry in the saved file is “2012-6-7 23:34:21 Notice 104500 DSL deactivate” and the file is timestamped 07/06/2012 23:34). Looking back, I realised that a re-sync the previous day had also occurred during an interactive login, although I had not noticed it at the time. My impression is that the modem processor is running near its max capacity, so extra tasks can cause a glitch.

It can be seen that the re-sync caused an increase in the downstream sync speed even though the downstream SNRM also increased back up to the target. Presumably this was because the Quiet Line Noise was slightly less than during the previous re-sync. However, the interleaving depth increased slightly – possibly due to DLM reacting to the re-sync?

GB33
                   (http://speedtest.net/result/1995819732.png)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on June 08, 2012, 11:40:22 PM
Hi GB33,

That really is interesting.
Thank you for sharing that information with us.

I have fairly recently measured my line with a surveyor's trundle wheel & allowing a few metres here & there for slack coils in joint chambers, up one pole & round the back of my house, I now believe my line to be a little short of 1000m.
It could perhaps be as short as 900m, depending on exactly where it crosses the main road to get to the cabinet.

I am hopeful that the exact route, materials used, cable diameters etc, will be confirmed in the not too distant future, so any remaining ifs & maybes can be put to bed once & for all.

How confident are you about 1000m being the realistic length of your own connection?

I was unable to see my stats when FTTC was installed 24th June 2011, but as you will be aware, I achieved really good speeds & stability for the first month.

My issues started immediately on my telephone & broadband services being reinstated following a sudden loss of service for 4 days at the end of July.

Since then all sorts of works have been carried out, including rerouting & providing a brand new drop wire, directly to my master socket, rather than being via an extension cable from the point of entry at the front of the house.

I can't imagine that any extra length has been introduced to my D-side cable, so the lower speed issue MUST be due to higher resistance in the cable or joints than was initially present.

In theory, as in your case (if memory serves me right from one of your other posts), speeds should have increased when switched to the 17a profile last October.
There was no immediate improvement at all.

I wish there were plans for a major refurbishment of the infrastructure in my area.
They could even site a cabinet or two in my garden at no charge, not even a peppercorn rent.

That was an interesting note regarding the saving of the modem's log file causing resyncs.

I don't usually bother to save it as my own logs contain plenty of detail, but I have thought of doing so to use as an easy reference of all known resync events.

I have saved it a couple of times (a long time ago), but can't recall if it is saved in some default location or we are offered the chance to browse to a location.
Could you confirm? I don't want to cause a resync at the moment.

I will soon be releasing updated scripts that will add more data to the ongoing log file without overwriting it.
I am just trying to finalise some error checking to combat what I believe is some sort of an occasional clash with AVG, during its daily virus scanning process.

Some days (not every day), a few minutes worth of data are missing from the ongoing modem_stats.log.
I have rescheduled the timing of the virus scans & the timing of the missing data moves with the new AVG schedule.
It's not that important really & it doesn't cause any other issues, so if I can't find a solution I'll either just accept it, or change to a different virus scanner, possibly giving Avast another try.

I see you are also on the recently adjusted band plan (now up to DS tone 3959 from 3939).
Do you have any before & after stats records from that adjustment?

Mine changed during the early hours of 24th May & I can see quite a large increase in US line attenuation from that time, along with a more gradual increase in attenuation since I started logging every minute back in late November (as can be seen in my 190 day stats).

It is at the higher frequency tones that neither of us can use due to attenuation over distance from the cabinet, but it does appear to have reduced my attainable DS & US rates a little.

It could be interesting for us to compare our stats occasionally, especially as we have such similar line lengths.

Cheers,

Paul.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Greybeard33 on June 09, 2012, 09:47:52 AM
Paul,

Thank you for your interest. Taking your questions in order:

1. 1000m (actually more like 995+/-10) is a rough estimate, made using Google Maps Pedometer, of the distance by road from my house to what I know is the correct cabinet (the OR installation engineer confirmed it) over what I believe is the correct route. It does include an estimate of the distance from the PCP to the FTTC cab (which is diagonally opposite on the other side of the wide road) but not any allowance for zigzags across the roads, coils in joint chambers etc., so is likely to be an underestimate. The route is not the only possible one, but is the shortest and most logical, considering the locations of the joint chambers and the other cabinets in the area. Before I ordered FTTC, I tried putting a string of addresses along this route into the BT Wholesale speed estimator, and the speeds progressively increased from my house up to the maximum near the cab - this was not the case for the other possible routes.

2. The modem web i/f has "Save" and "Save As" options for the log file - I chose Save As, then browsed to a suitable folder on the PC hard drive. When I clicked Save in the dialog box, I was thrown back to the modem's login page and had to log in again, so clearly there was a major hiccup. I do not know what the Save option does, and am not keen to try it!

3. I use Microsoft Security Essentials not AVG, but am unable to account for the 35 minute gap in the stats I posted yesterday - there was no virus scan at the time. The Task Scheduler Task Status record shows Task Result - Success every minute until 12:25:00, then nothing until 12:59:13 Run Start, 12:59:13 Run End, Result - Stopped; then 12:59:13-12:59:16 Stopped, repeated once; then 12:59:13-12:59:17 Success, repeated 30 times; then 12:59:59-13:00:00 Success and continuing normally every minute thereafter. The modem_stats.log just skips from 12:25 to 12:59 (single entry only). The PC was idle but awake and the Windows Event Log shows no events at all during this period. Incidentally I had to tweak the Task Properties to get it to run automatically after a reboot  - Googling the error turned up the solution of changing, on the Settings tab, the setting for "If the task is already running, the following rule applies:" to "Stop the existing instance". Don't ask me why this works! (I'm running Vista SP2)

4. Unfortunately my earliest stats are from 1st June and the band plan had already changed to tone 3959 by then. Therefore I cannot say if the change had any significant effect, although in some recent speed tests my upstream rate has been a little better than I have ever seen previously.

I hope your persistence will eventually see you triumphantly posting stats better than mine!

Cheers,

GB33
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on June 09, 2012, 10:16:45 AM
Hi GB33,


2. The modem web i/f has "Save" and "Save As" options for the log file - I chose Save As, then browsed to a suitable folder on the PC hard drive. When I clicked Save in the dialog box, I was thrown back to the modem's login page and had to log in again, so clearly there was a major hiccup. I do not know what the Save option does, and am not keen to try it!

Mine (version 2B) just has a Save Log button - screenshot attached.
I'm not keen to keep experimenting at this stage either & it's not of tremendous importance anyway.
 
Quote
3. I use Microsoft Security Essentials not AVG, but am unable to account for the 35 minute gap in the stats I posted yesterday - there was no virus scan at the time. The Task Scheduler Task Status record shows Task Result - Success every minute until 12:25:00, then nothing until 12:59:13 Run Start, 12:59:13 Run End, Result - Stopped; then 12:59:13-12:59:16 Stopped, repeated once; then 12:59:13-12:59:17 Success, repeated 30 times; then 12:59:59-13:00:00 Success and continuing normally every minute thereafter. The modem_stats.log just skips from 12:25 to 12:59 (single entry only). The PC was idle but awake and the Windows Event Log shows no events at all during this period. Incidentally I had to tweak the Task Properties to get it to run automatically after a reboot  - Googling the error turned up the solution of changing, on the Settings tab, the setting for "If the task is already running, the following rule applies:" to "Stop the existing instance". Don't ask me why this works! (I'm running Vista SP2)

That's strange, but very handy to know.
It's not necessary on Windows 7 & XP.

Quote
4. Unfortunately my earliest stats are from 1st June and the band plan had already changed to tone 3959 by then. Therefore I cannot say if the change had any significant effect, although in some recent speed tests my upstream rate has been a little better than I have ever seen previously.

Not to worry. My DS & US do appear to have taken a slight hit since the change.
It may just be pure coincidence that US LIne attenuation shot up at the same time. It doesn't look too out of the ordinary on your connection.

Quote

I hope your persistence will eventually see you triumphantly posting stats better than mine!



I'm not holding my breath on that one.

I would love to know though whether my stats are currently as good as they could ever physically be, or if they did indeed deteriorate following the 4 day loss of service (i.e. "something" just needs repairing).

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Greybeard33 on June 09, 2012, 01:00:48 PM
Mine (version 2B) just has a Save Log button - screenshot attached.
Mine is the same - my memory let me down. The Save As dialog must have come up after I pressed the button.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 19, 2012, 07:13:59 AM
Just for fun, I attach the graphs from the latest 60 days connection.

During that period most of the resyncs were caused by me either rebooting the modem for testing purposes, or having to turn all the power off while I do some home refurbishing work.

I believe I have now exceeded the record for my connection's up time. It has now gone over 10 days without a resync.

Sync speeds aren't fantastic due to distance from the cabinet of up to 1000m or maybe a little less, but the connection is stable.

(http://www.speedtest.net/result/2188480096.png)

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on September 20, 2012, 11:48:29 PM
You got your connection sorted then BE  :) What was the cause?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on September 21, 2012, 01:54:21 AM
Quote
What was the cause?

Argh! Darren, no!  :no:  Please don't get Baldy_Bird started . . . he might just use it as an excuse to fill another 40 pages whilst explaining it to you!  :help:  :paperbag:
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on September 21, 2012, 06:26:05 AM
You got your connection sorted then BE  :) What was the cause?


In the end, it came down to a faulty faceplate filter that was causing disconnections simply by using the phone & a dodgy joint between the underground cable & the pole top DP across the road from my house that caused random disconnections, increasing in frequency as the weather became warmer & dryer.

Some of the other engineer/technician visits where "work" was done caused slight improvements (usually simply by re-making poor cable joints & onceover replacing/rerouting the drop wire from the pole).

I believe the dodgy joint had been the main issue all along & the faceplate issue being more recent as a number of faceplates had been replaced previously, with no real improvement seen.

We had a power cut yesterday morning that resulted in a slight increase in DS & US sync & throughput speeds:-
(http://www.speedtest.net/result/2192814580.png)

From experimenting with different things over the problematic months, I/Plusnet discovered that my DS sync speed increases by around 5Mb - stabilising at approx 33.5Mb when US is capped at 2Mb, rather than what has now become Plusnet's default "up to" 10Mb.

This also appears to be the position for other sub-40Mb users on being switched to the 10Mb US service.

Users capped at 40Mb but with higher attainable rates still achieve 40Mb sync speed with the benefit of increased US sync speed.

Even before 10Mb US became the default Plusnet offering, I chose to have the increased US throughput speed at around 4Mb instead of 1.67Mb, at the expense of some DS throughput speed due to the nature of how I work from home fairly often.

My gripes over this matter are about how long it took to actually find & fix the faults & the constant "your connection is working perfectly satisfactorily & within our supplier's" guidelines" type of comments, despite me providing graphical & raw data evidence to the contrary.

Even reporting a number of times that engineers simply climbing the pole to work on other users' lines caused disconnections, thus highlighting a probable loose joint issue took over 3 months to be even looked at & that was only because I begged the visiting engineer to check it out. It hadn't been mentioned to him by BT (or Plusnet's notes).
In the end, that turned out to be the main culprit.

So, all in all, it was a very astute decision on BT's behalf to supply locked modems where probably the vast majority of users have absolutely no idea how poorly their connections may be performing at any time & thus fault reports are kept to a minimum & it is incredibly difficult to dispute BT's claims that their aged infrastructure is "fit for service".

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: JoshShep on January 17, 2013, 11:24:18 AM
Hi Guys,

Long time no speak! It's been a while since I've been on here.

Just thought I'd check how your all doing? And this directed at Paul, how has your connection been?

You finally happy with your results?

Cheers,

Josh.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on January 17, 2013, 01:02:36 PM

Just thought I'd check how your all doing? And this directed at Paul, how has your connection been?

You finally happy with your results?



Yep, the connection has been really stable, albeit that I chose to have a higher US profile at the expense of a little DS speed as I transfer many large files between home & the office when working from home.

It did take a few Mb DS hit 31st December that I will look into at some time (no real urgency though).


How's you and your connection doing?


P.S. more efficient and robust compiled programs are about to be released (soon).

The output is basically the same appearance as the script versions, but there is more of it to look at & it is now all harvested & generated much quicker & reliably than the script versions, using a basic text based ini file for users to easily configure drive & folder locations, some colours, pauses/delayed harvesting etc.


Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on February 05, 2013, 10:54:48 AM
one thing i learned is so many people get their distances wrong.

I see people thinking they 200m then they post their stats which indicate they double that distance.

On google maps I am 200 metres but my attenuation indicates I am 400-450m instead.  At that distance I was estimated at 65.9 down and 20 up.  I initially got 80/20 with a attainable of 110/36, it went down to 90/36 after 2 weeks and then down to 73/22 after 3 weeks and I have been there since.  A few on this forum have found it odd I had such large drops tho.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Theagg on February 06, 2013, 01:04:24 PM
one thing i learned is so many people get their distances wrong.

I see people thinking they 200m then they post their stats which indicate they double that distance.

On google maps I am 200 metres but my attenuation indicates I am 400-450m instead.  At that distance I was estimated at 65.9 down and 20 up.  I initially got 80/20 with a attainable of 110/36, it went down to 90/36 after 2 weeks and then down to 73/22 after 3 weeks and I have been there since.  A few on this forum have found it odd I had such large drops tho.

Yes, as regards attentuation and SNR values reported in the logging software, can someone here give a rough guide, assuming the line itself has no problems, as to what values you can expect for a given distance.

Example, my cabinet is around 320m away. My SNR is 5.7db for this and my dowsnstream attentuation across the bands (D0, D1, D2) reads 12.9db, 30.8db, 48.1db. So would those be the expected ballpark values for that distance, or do those figures either indicate potential issues with the line, assuming approx 320m, or that the actual route the line takes is longer ?

(An Openreach engineer who visited shortly after installation noted that there were errors on the line, that required him to go check the cabinet, after which he would pop back. But I never heard anything from him after that, since he didn't return.)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on April 20, 2013, 04:57:27 PM
my guess is based on that attn your line is 500-550m.

Remember the twists add distance, spare cabling, possible indirect routes, distance up pole etc.  Also that the cable run goes from the normal cabinet to VDSL cabinet and then back again before heading to your house.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Bald_Eagle1 on March 02, 2014, 01:54:23 PM
Resurrecting an old thread, but FWIW, I have just found a "Chart of BT fibre broadband FTTC (VDSL2) speed against distance from the cabinet"

http://www.increasebroadbandspeed.co.uk/2013/chart-bt-fttc-vdsl2-speed-against-distance

My line length has now been confirmed as between 1000m & 1100m & I currently see see sync speeds of around 22Mbps DS & 5Mbps US.

I was able to achieve around 30/7 before crosstalk kicked in as more users were connected via my cabinet, which was almost at full capacity when last checked by a visiting engineer.


Roll on Vectoring..................................


Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: covlad1987 on March 02, 2014, 02:03:46 PM
Resurrecting an old thread, but FWIW, I have just found a "Chart of BT fibre broadband FTTC (VDSL2) speed against distance from the cabinet"

http://www.increasebroadbandspeed.co.uk/2013/chart-bt-fttc-vdsl2-speed-against-distance

My line length has now been confirmed as between 1000m & 1100m & I currently see see sync speeds of around 22Mbps DS & 5Mbps US.

I was able to achieve around 30/10 before crosstalk kicked in as more users were connected via my cabinet, which was almost at full capacity when last checked by a visiting engineer.


Roll on Vectoring..................................

i found this one on think boardband http://www.thinkbroadband.com/guide/fibre-broadband.html



200m    65 Mbps    18 Mbps    20% hmmmmmm thats how far im from the green cabinet and now bt saying my max is 47mbps but my router show sync 55mbps data 49mbps but down load 47mbps ip profile 47mbps the fight carrys on lol
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on March 04, 2014, 02:44:49 AM
Resurrecting an old thread...
Apologies, I asked about your conection earlyer in the thread and failed to notice your reply.. how time flys..

So essentially your low speed is down to line length and crosstalk with a few faults along the way, some or all of which have been fixed. What a journey and indeed roll on vectoring, and with any luck FTTdp then full fibre.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 04, 2014, 10:01:43 PM
Still a bit to go before Vectoring becomes reality. Lots and lots of data from the initial trial, but in summary, 65% saw an increase with the trialled vectoring engine used, with 23% of those users seeing an increase greater than 25% of their pre-vectored rate.
 
The next trials are using a different engine, to see if further gains can be made ?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 04, 2014, 10:12:22 PM
Would you be able to disclose if the initial trial was on both Huawei and ECI equipment or just one of them, please?
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 05, 2014, 07:18:52 AM
Would you be able to disclose if the initial trial was on both Huawei and ECI equipment or just one of them, please?

Just Huwaei, Alan, and if memory serves on the '48' only Cab. The next trials will be on a '96'. The trials are extremely in-depth, and haven't been a case of, 'This will do'. I think they're planning that the next vectoring engine to be trialled, will reap even more reward ??
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 05, 2014, 02:09:11 PM
Black sheep 'if' the next trials are Huwaei only can you push internally as to why this is the case?

Given that rumours are the eCI equipment will be more expensive for BT to vector and BT may even skip vectoring on ECI altogether it doesnt bode well they not even trialling on eCI :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 05, 2014, 07:44:38 PM
Good God, Chrysalis ……… I'm a lowly engineer, a piece of …. on somebody's shoe. I wouldn't get past the first hurdle, or even be given a reasoned excuse as to why they are doing what they are doing.

Lets not go getting all flustered with knee-jerk reactions, just yet. I know Jack about 'Vectoring engines' and/or their capabilities. As you say, it is just "rumours" about the ECI upgrade expense, and until all trials are completed and Openreach can be confident in vectoring as a sustainable product in regard to DSL speeds, then it's business as usual I'm afraid.

I can't comment on OR's behalf, but in my own opinion they are not going to deploy vectoring to just the one vendor. They are probably trialling Huwaei as I believe they were vector-ready to some degree, whereas ECI weren't ?? It's long months away, whatever the reality of the situation is, so until then …….. it's goodnight from ……….. whoops, slipped into a sketch there for a moment.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 05, 2014, 08:57:31 PM
<snip>
They are probably trialling Huwaei as I believe they were vector-ready to some degree, whereas ECI weren't ??
<snip>

That agrees with my very limited understanding . . . A Huawei SmartAX MA5616 would need an expansion card-cage & card(s), a Huawei SmartAX MA5603T would just need card(s) but an ECI MiniShelf M41 would have to be swapped out as an entity and replaced with an ECI MiniShelf V41.

I cannot imagine a part-implementation of the "vectoring" solution . . . so let's leave the wizards of Grimbledon Down to their testing and then review the situation in 12 months time.  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 05, 2014, 09:06:55 PM
Absolutely agree, Mr Cat .  ;D
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on March 08, 2014, 06:18:16 AM
Interesting. I rather hoped they would have started to roll it out by the end of this year. Oh well.

I wonder if trialing a new engine means either A) the trial is a sucess, vectoring will be rolled out just trying to maximise benefit first. or B) Results weren't good enough and vectoring won't be rolled out unless the new engine provides better results.

Quote
I cannot imagine a part-implementation of the "vectoring" solution
Nor can I and hopefully the rollout doesn't depend on the results also being good on ECI.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 08, 2014, 11:25:48 AM
Also bear in mind BT probably dont consider it urgent like we do.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 08, 2014, 03:23:41 PM
Nah, we're just sitting back and resting, might get round to it in a couple of years if we can be ar5ed.  :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 08, 2014, 03:41:40 PM
What I mean is if you sitting in BT's board room, you not going to be bothered if someone has 60mbit/sec instead of 80mbit/sec, as for the most part 60mbit/sec is good enough.  So its unlikely BT are considering this as urgent, they probably trial various things that dont see the light of day, just keeping their options open.  They will only really care about if enough people get a certian speed that allows them to market that speed to comply with ASA regulations.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on March 08, 2014, 09:55:54 PM
Of course, BT have an R&D department, would be silly to believe otherwise. I think you underestimate their urgency, BT have said themselves they see vectoriing as a speed enabler so the focus isn't solely on the higher speed end.

A couple of years takes the mic Black Sheep, there will be no bickys with your cuppa if you don't get of your back side and get back to work :P :lol:

Just read something interesting WWWombat wrote on TBB..

Quote
BTW, I've seen that a BT engineer is due to talk about the results of their G.fast trial in April in Paris. Surely we'll hear about vectoring before that one!
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 08, 2014, 10:40:41 PM
They may see it as a speed enabler, they may plan for future rollout, but that doesnt mean they see it as urgent.

eg. They were testing adsl2+ for 4 years before they rolled it out.

BT first did vectoring testing over 2 years ago according to a ofcom document.

If it was urgent they would be rolling it out now not testing and talking about it. :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: NewtronStar on March 08, 2014, 10:47:51 PM
They may see it as a speed enabler, they may plan for future rollout, but that doesnt mean they see it as urgent.

eg. They were testing adsl2+ for 4 years before they rolled it out.

BT first did vectoring testing over 2 years ago according to a ofcom document.

If it was urgent they would be rolling it out now not testing and talking about it. :)

But will the price be right for the consumer  ;)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on March 09, 2014, 12:11:36 AM
I didn't say they do see it as urgent, I said I think you underestimate their urgency. Which IMO is greater than you seem to imply.

Testing it instead of rolling it out strait away doesn't mean their taking their time. It's what BT do, test, then rollout. If the testing takes 4 years so be it, doesn't mean their taking their time, just means it's taken that amount of time to reach a stage where rollout can go ahead. :)

Talking about the results of the recent vectoring trials is a good indicator rollout is sooner rather than later, they would'nt talk about them publicly otherwise IMO.

Will be interesting to see what, if anything transpires over the next next 4-6 weeks. I'm very intrigued what improvements it can bring to the wide variety of lines.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 09, 2014, 03:58:12 AM
Well said, Darren.

If they rushed it through without proper in-depth analysis, then certain members of this forum would be quick to slag them off when it would inevitably fail.  ;) ;D ;D

I don't care what the Ofcom paper says, the vectoring trial only started last year. This was using the FGPA Vector Engine which returned varying results. The very clever men who know more than us, have now said they wish to continue the trial using the new ASIC Vector Engine, as they are confident improved results will be returned.

So, 'urgency' is deemed as long as it takes to perfect the technology, not jumping because a low percentage of DSL users demand it. Patience is a virtue.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: c6em on March 09, 2014, 09:54:03 AM

As well as testing for cross talk from other lines I would hope they are testing where cabinets are placed in electromagnetically noise areas and the effect this environment has on the cabinet/cross talk correction routines.
So for one example cabinets near to railways lines.

As with all fast moving technology the problem is always the same from a purchasing evaluation point to view.
1. Do you buy established safe existing tech 'now' and risk being out of date earlier.
2. do you wait until better tech comes along so be more up to date for longer but at the cost of maintaining existing sub-optimal current systems for longer to your detriment.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 09, 2014, 03:31:50 PM
Well said, Darren.

If they rushed it through without proper in-depth analysis, then certain members of this forum would be quick to slag them off when it would inevitably fail.  ;) ;D ;D

I don't care what the Ofcom paper says, the vectoring trial only started last year. This was using the FGPA Vector Engine which returned varying results. The very clever men who know more than us, have now said they wish to continue the trial using the new ASIC Vector Engine, as they are confident improved results will be returned.

So, 'urgency' is deemed as long as it takes to perfect the technology, not jumping because a low percentage of DSL users demand it. Patience is a virtue.

So you just confirmed what I said really.

You guys trying to argue with me over nothing.

In regards to the ofcom paper, I doubt ofcom are lieing, more likely this trial that started last year was the first field trial using customer lines.  BT have trialed the actual technology before that.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 09, 2014, 07:55:31 PM
On the contrary.

I have said the trials will continue until BT are satisfied the product is fit for purpose. You have said BT aren't being "Urgent" enough about it. Completely different takes on the subject, and I am not agreeing with you I'm afraid.

Once again, it seems that it doesn't matter what I say, you dismiss it out of hand and prefer the 'Slag BT off' route.  :no: :no:
Fed up with it now.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 09, 2014, 09:11:51 PM

As well as testing for cross talk from other lines I would hope they are testing where cabinets are placed in electromagnetically noise areas and the effect this environment has on the cabinet/cross talk correction routines.
So for one example cabinets near to railways lines.

As with all fast moving technology the problem is always the same from a purchasing evaluation point to view.
1. Do you buy established safe existing tech 'now' and risk being out of date earlier.
2. do you wait until better tech comes along so be more up to date for longer but at the cost of maintaining existing sub-optimal current systems for longer to your detriment.

Barnet and Braintree were chosen for the trials, as Braintree is a quiet area in terms for RFI (radio frequency interference), while Barnet was relatively noisy, having a number of RF transmitters for local radio stations nearby.
Vectoring can only deal with crosstalk noise, it cannot deal or try to cancel noise from other sources RFI or REIN (Repetitive Electrical Impulsive Noise). Hence by using those two locations they hoped to be able to identify if there was any differences, if Vectoring was enabled (reducing crosstalk noise) in an area with high levels of RFI, compared to low levels.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on March 09, 2014, 11:00:53 PM
You guys trying to argue with me over nothing.
That's not my intention, all I intended was to express my opinion, which was that I disagree BT have vectoring on the back burner.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 11, 2014, 12:27:20 PM
On the contrary.

I have said the trials will continue until BT are satisfied the product is fit for purpose. You have said BT aren't being "Urgent" enough about it. Completely different takes on the subject, and I am not agreeing with you I'm afraid.

Once again, it seems that it doesn't matter what I say, you dismiss it out of hand and prefer the 'Slag BT off' route.  :no: :no:
Fed up with it now.

ok we will have to agree to disagree then.

urgent means has to be done now.

eg. in my work like BT I tend to test things first before putting them in place, as I dont want things to break.  This is what I do most of the time as normal process.

However if a customer tells me they want something urgently, I either completely skip testing and just put it in place or I do very minimal testing, clearly we have different definitions of urgent.

Plus you openly said in your post I consider vectoring more urgent than BT does, which is exactly what I said, so you now disagreeing with yourself :)

I understand they your employer, you dont want to say anything bad about them at all in public, but there isnt anything bad about not been urgent I wasnt attacking BT.  I was just saying they dont consider vectoring as urgent.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 11, 2014, 12:30:39 PM
You guys trying to argue with me over nothing.
That's not my intention, all I intended was to express my opinion, which was that I disagree BT have vectoring on the back burner.

I didnt say they had it on the back burner.

Something can still be a priority without been urgent.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 11, 2014, 03:44:32 PM
On the contrary.

I have said the trials will continue until BT are satisfied the product is fit for purpose. You have said BT aren't being "Urgent" enough about it. Completely different takes on the subject, and I am not agreeing with you I'm afraid.

Once again, it seems that it doesn't matter what I say, you dismiss it out of hand and prefer the 'Slag BT off' route.  :no: :no:
Fed up with it now.

ok we will have to agree to disagree then.

urgent means has to be done now.

eg. in my work like BT I tend to test things first before putting them in place, as I dont want things to break.  This is what I do most of the time as normal process.

However if a customer tells me they want something urgently, I either completely skip testing and just put it in place or I do very minimal testing, clearly we have different definitions of urgent.

Plus you openly said in your post I consider vectoring more urgent than BT does, which is exactly what I said, so you now disagreeing with yourself :)
I understand they your employer, you dont want to say anything bad about them at all in public, but there isnt anything bad about not been urgent I wasnt attacking BT.  I was just saying they dont consider vectoring as urgent.

Where have I said that I consider vectoring more urgent than what BT do ???
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 11, 2014, 04:57:54 PM
Baldy Bird's thread has been comprehensively hijacked . . .  :'(

[Edited to correct the mishap.]
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Black Sheep on March 11, 2014, 05:09:30 PM
It's, 'Has been', Mr Cat.  :P
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: burakkucat on March 11, 2014, 05:28:41 PM
 :paperbag:  <-- Sad cat hides.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: kitz on March 11, 2014, 06:03:45 PM
d'oh I missed the tryp0?  Was it haz beens or baked beans?

Seriously though theres no point squabbling, at the end of the day BT will take their time as they usually do when it comes to new technologies. I have to agree that they do seem to take their time, but BT do often test, test test again and then come up with their own version.   I believe the trials BS mentioned are the first 'live' trials which historically tends to mean that if all goes well then it will slowly be rolled out to the rest of us.  I believe Plusnet were getting feedback on the tests too as they have several customers who are on the trials.

The ECI cabs could prove problematic because although vectoring can be done at a line card level, its not as efficient as a standalone vectoring module.  By efficient I mean in terms of spare lines and manual intervention.  The nearest I can equate it to is wanting to add a new PCI card into your PC, but youve run out of PCI slots.  The ECI cabs dont appear to have room or capability for a new module to be added, so its anyone's guess yet how BT will proceed with the ECIs.

I think we can all agree this technology is much needed and I have a suspicion that even BT may have been a bit unaware of just how much crosstalk would affecting some vdsl2 lines.. mines now nearing 20Mb and I wasnt even 1st on the cab. 

Whilst BT are far from perfect, they are still one of the few UK companies held in high esteem when it comes to telecoms technology world-wide.  Despite niggles if you look at the wider picture they do mostly tend to get things right.   We may not have the fastest speeds, but at least it isnt just limited to one or two major cities. Love them or hate them, there isnt any private company who could do a much better job and still remain in profit...  even though they may be slow when it comes to new technologies.

Anyhow, hopefully this thread can now get back on track :)
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on March 11, 2014, 06:45:16 PM
yeah I am not bothered and sorry for the siderailing.  I thought my comment was harmless and I apologise it offended some people.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Darren on March 12, 2014, 06:12:17 AM
hmm, a few points I feel I need to set straight before I move on from this disaster of a conversation.

I didn't think you were attacking BT Chrysalis and I wasn't defending BT, nor do I work for them. I was certainly not offended so no need to apologise, if that was directed at me.

It's clear now you were talking from your own perspective instead of BTs, hence the difference of opinion.

Posting on forums isn't something I do much nowadays, simply becasue I can't be bothered dealing with the inevitable missunderstandings that faceless communication brings. Hopefully we understand where each of us were coming from now and you have no hard feelings.

Anyway, looking forward to some vectoring results.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: bignose2 on December 05, 2014, 05:11:02 PM
HI,

I now an old thread but thought I would add my 2 p as I could not find similar info anywhere but stumbled on this thread in searching.

Been waiting expectantly for FTTC & had rather given up with but all of a sudden'ish BDUK came through and enabled today.

I am 99% sure I am 750m from cabinet (Certainly no less, only 1 possible route to my house, annoyingly it goes past 40m & back again so 80m unnecessarily, again I know this as have been with engineers when trying to fix previous faults).

I know I have good copper, partially as I have seen what looks like newish connectors & cable in the man hole & I use to get 7+ MB from adsl on over 3km from exchange (BT estimates 3mb) so can assume the "last mile" has got to be pretty good to excellent. All underground.

Because of this, I would not get your hopes up but I really think nice to know of potential much more that I I ever imagined.

I am also first on the cabinet but quite rural so hope not too have much crosstalk but starting point of this is quite amazing.

Anyway a variety of speed tests all confirm 71mb Down & 17mb UP & file downloads timed, as I could not believe it.
I am sure there is nothing special about this cabinet, no vectoring or anything as these figures would seem to defy even the best estimates.

BT checker was max Clean 46 - 65 and I think that uses house location and I know this line goes an extra 80 meters and my drive is a further 100+ meters to the BT socket so even I thought 65 would be very optimistic.

I had guessed I might get just over 40mb & 7up & if lucky high 40's & 9mb up. worst case I assumed about 35mb.

Only been on 12 hours so will see how stable but no glitches so far.

Apart from the original useless BT (Freelance) installer for TalkTalk. He only got 13mb down on test for about 5 seconds, then nothing, no connection at all, said that would be fine, perhaps not fully activated as first on cabinet (perhaps true). I did say this really did not seem OK but hard to argue. come morning, still nothing. Because he had signed off as completed! (not sure what definition he used) it then was down as a fault. so remote tests, more remote tests & because it would get a connection for perhaps a few seconds now & again that was considered OK, so escalated then not, so no engineer appointments. Eventually BT out today and said wires had not been pushed home in the cabinet. Monday install, working Friday.. not good.

DSL synchronization status:
Up
Connection status:
Showtime
Upstream line rate (kbit/s):
19999
Downstream line rate (kbit/s):
76772
Maximum upstream rate (kbit/s):
21215
Maximum downstream rate (kbit/s):
75112
Upstream noise safety coefficient (dB):
8
Downstream noise safety coefficient (dB):
6.2
Upstream interleave depth:
0
Downstream interleave depth:
0
Line standard:
VDSL
Upstream line attenuation (dB):
31.2
Downstream line attenuation (dB):
15
Upstream output power (dBm):
7.6
Downstream output power (dBm):
12.3
Channel type:

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: kitz on December 07, 2014, 02:43:17 PM
Hi and welcome :)

That does seem very good for 750m.  As regards to the BT estimates they are often conservative to cater for the less than optimal lines..  and Im sure they also perhaps factor in something in anticipation of crosstalk.

Im sure Ive probably already mentioned in the this, but BT's original estimate for my line was "Up to 62.6 Mbps" and that was before they even started on the Impacted range which now says 50.5Mbps.   I was far from the first on my cab (port 25) yet when I first got connected my max attainable was 108Mbps, so goodness knows what I could have got if I was one of the first - possibly double what the BT estimate said? 

Because it sounds like you are the first on the cab, then as more people join, then your current speed will gradually decline. So far Ive lost about 30Mbps to crosstalk and Im sure its not done with me yet as I lost 5Mb just a couple of weeks ago.   I gained a bit back by using my own router which gives a higher bit rate, but unless they roll out vectoring soon, then everyones speeds continue to decline :(

Quote
Eventually BT out today and said wires had not been pushed home in the cabinet. Monday install, working Friday.. not good.
  I cant help but wonder how much money BT have 'saved' by using contractors.  I suppose the majority do a decent job, but we do hear an awful lot which have gone wrong whereby the use of a contractor has meant a subsequent BT visit required.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: ih on December 07, 2014, 04:15:39 PM
I think my max attainable was something like 132Mbit down, 30 or 40Mbit up. I was the second connection on the cabinet (must have been the first day of service) and a rock solid 40Mbps sync for the time. This may have been before BT rolled out profile 17a, but I don't know if the Huawei's calculation is based on that.

Now it's more or less the 72Mbit that I sync at (this is a slight improvement on before, used to be 65Mbps unless I resync during a power cut) and 27Mbit up. I am approximately 350-400m from the cabinet, more or less just up the road from me.

I hope vectoring happens soon (I hear Ireland/Eircom are already doing it). It's also annoying that I've seen some very rural FTTP deployments by BT, and in my own village precisely one road (not EO, there's a copper cabinet and it's closer to the exchange than I am) got FTTP. I guess for the rest of us it's going to be some combination of pair bonding/vectoring/profile 30a to get speeds up.

76Mbit on 750m does sound very good though.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: bignose2 on December 07, 2014, 11:25:06 PM
Yes,

Being quite/very rural I hope & quite optimistic that I do not get too much crosstalk because there are only 7 or 8 houses between me & the cabinet but a small'ish hotel that is 200m further on which is much more of a worry.

A few more houses further on & that's it in my direction. Will they all take FTTC up anyway? probably, eventually.

I am not sure how many connections are needed before a real impact but surely on housing estates there could be dozens or more all going down the same ducting.

I guess at this distance the impact will probably be more significant but either way still much better than before. Wondering the fact that I must have good quality line may either make cross talk worse as strong signal or perhaps if better if insulation might not suffer as much.

Sync speed had dropped because I had a restart 12 hours ago, I think must have had power disconnect or something, hopefully not signal problems as been rock steady otherwise & only this one dsl restart. Max attainable actually went up to 79mb!! but line rate is 67mb with speed tests at 62mb.
I am  not sure why this would sync slower on higher Max, I know first few/10 days DLM adjusts but would one disconnect not make a difference.

As new to FTTC not sure how informative SNR is. Been steady day & night 6.0-6.2.
On ADSL use to vary quite a bit over the day. Gradually dropping 3  from daytime peak, overnight. During the day on restart I could sometimes sync as at a higher than normal rate & keep 6snr, but over night this could go as slow a 2 & perhaps drop out, rare. If it re-syncs then as a slower speed I get a more healthy 24hr snr and no disconnects ever. With TT so they did not use DLM & would not change SNR levels unless requested but understand fibre is all DLM.

Going to leave it & make sure not accidentally un-pluged.

Trouble is this contractor! said you cannot extend the Master Socket, I use to have my ADSL 7m away via quality cat5e cable & he said he could not do anything with that so now the router sits by the front door a little exposed. I am fairly sure this was also c**p as lots of people seem to have extensions. Was not worth arguing at that point, easy enough to rewire the cat5e as direct ethernet to port on my router anyway. With such a good speed I thought I would not mess anyway for now & leave it there.

I still happy that the starting point is so high, If I had begun with perhaps low 40's then lots of crosstalk down to 30 or even less, whilst still great it would be a shame to be finally on fibre & not enjoy the full benefits.

Will anxiously watch over the next few weeks/months. I guess the hotel will be hot on my heels & that is the one to watch.

thanks for your comments.

Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: NewtronStar on December 07, 2014, 11:52:18 PM
I am  not sure why this would sync slower on higher Max, I know first few/10 days DLM adjusts but would one disconnect not make a difference.

The DLM kicks in on the 2nd day for a new FTTC install, and the 10 days is an openreach thing meaning they won't investicate a possible line fault until the 11th day or there after  :(
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: bignose2 on December 08, 2014, 12:10:20 AM
Thanks for that, do you think the DLM has just slowed me down or could it be errors.

I can't find the the stats on this HG635.
or is this
Internet stats:
INTERNET_TR069_R_VID_101
INTERNET_TR069_R_ETH1
Other_B_0_65
INTERNET_TR069_R_0_38
.... the same thing perhaps under a different name. All of the above have 0 under the errors heading.

Can't find CRC's anywhere.


I really don't like this hg635, port forwarding seems stupid & nothing is anything like the many modems I have had before, even the hg533 were much nicer than this.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: bignose2 on December 08, 2014, 12:16:15 AM
Following on, just looked at my log
10:02:13 07/12/2014   User Level   Notice   CWMP:Cwmp post inform success.
10:02:13 07/12/2014   User Level   Notice   CWMP inform message: parameter change.
10:02:13 07/12/2014   User Level   Notice   CWMP inform message: event: 4 VALUE CHANGE.
10:02:09 07/12/2014   System   Notice   WAN connection INTERNET_TR069_R_VID_101:IPv4 connected.
10:00:38 07/12/2014   System   Notice   DSL connection is active.
10:00:11 07/12/2014   System   Notice   WAN connection INTERNET_TR069_R_VID_101:IPv4 disconnected.(ERROR_NO_CARRIER)
10:00:11 07/12/2014   System   Notice   DSL connection is disactive.

Almost exactly 2 days after engineer fixed my connection and got it working, 10am 2 days earlier, after bum install.
Just wondered what the parameter change & Value change could refer to, poss a reset by DLM (I guess unlikely) but why slower..

this is why I would like to find the true error count.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: les-70 on December 08, 2014, 07:48:52 AM
  If you want to see your errors and stats see http://forum.kitz.co.uk/index.php?topic=14185.msg273545#msg273545.   It would be best to also read surrounding posts and the latest ones.  It is at your own risk but it is only a config file and can't hurt the HG635 itself. 
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: Chrysalis on December 09, 2014, 12:17:28 AM
my original estimate was 65.9, my attainable when I first unlocked modem was 110, it did go down to 50 at one point and I am now at low 70s.
Title: Re: FTTC - Distance from the Cabinet - Realistic speed estimate
Post by: GigabitEthernet on April 11, 2015, 06:41:01 PM
I am 99% sure I am 750m from cabinet (Certainly no less, only 1 possible route to my house, annoyingly it goes past 40m & back again so 80m unnecessarily, again I know this as have been with engineers when trying to fix previous faults).

I know I have good copper, partially as I have seen what looks like newish connectors & cable in the man hole & I use to get 7+ MB from adsl on over 3km from exchange (BT estimates 3mb) so can assume the "last mile" has got to be pretty good to excellent. All underground.

This thread will never die!

Your line sounds very similar to mine. I am around 750 to 800m from the cabinet, perhaps a bit more or less. My line is mostly overhead but has always been above average. The entire cable between the DP and my house was replaced a few years ago and since then I've got a constant 7.5+ Mb sync despite being 3km from the exchange (42dB-ish attenuation).

I hope my experience is like yours! I now have an FTTC cabinet but orders are not available yet. I assume it's still working well for you?