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[waltergmw]

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

[Bald_Eagle1]

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.

[waltergmw]

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

[Bald_Eagle1]

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.

[attachment deleted by admin]

[razpag]

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.

[Bald_Eagle1]

@ 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.

[razpag]

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'.

[Bald_Eagle1]

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 


Paul.

[waltergmw]

@ 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

[Bald_Eagle1]

@ 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.

[razpag]

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. 

[burakkucat]

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

Line Tested O.K.

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."

[waltergmw]

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

Kind reagrds,
Walter

[attachment deleted by admin]

[silversurfer44]

burakkucat >> the first thing to say is "Can you hear that?"

I would have thought "Sorry I can't hear you for the crackling!"

[Bald_Eagle1]

@ 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.