Kitz Forum
Broadband Related => ADSL Issues => Topic started by: limbo on September 07, 2011, 12:54:39 AM
-
Hi there,
Retyped this all since I lost it the first time because I had an attachment over 900kB! :wall:
I'm new to this forum, but from the few posts I've read, it seems to me that there are a lot of experienced engineers and troubleshooters around!
So we have been with BT since 2004, and we first started with 1/2 Mbps. This was then upgraded to 1Mbps. However it seems to have dropped now (for a good few years) to 333Kpbs. Take a look at a test I ran earlier this evening (theses stats are fairly standard for our connection. It is odd that the upload speed is faster than the download speed!):
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fwww.speedtest.net%2Fresult%2F1469826642.png&hash=bfaf93f0c7ad60d391a64e0128abeeb802249254)
According to the BT line speed tester, it reckons we should get 1Mbps.
I've had a look at the Kitz Exchange Checker, and these are the figures it gives:
Distance:- Direct: 2.59 km
(appx)* By Road: 3.22 km
Here is some data I pulled from the BT Homehub 2 earlier:
ADSL line status
Connection information
Line state Connected
Connection time 0 days, 2:42:50
Downstream 575 Kbps
Upstream 462 Kbps
ADSL settings
VPI/VCI 0/38
Type PPPoA
Modulation ITU-T G.992.5
Latency type Interleaved
Noise margin (Down/Up) 8.9 dB / 7.6 dB
Line attenuation (Down/Up) 55.5 dB / 29.8 dB
Output power (Down/Up) 17.0 dBm / 12.0 dBm
Loss of Framing (Local) 53
Loss of Signal (Local) 196
Loss of Power (Local) 0
FEC Errors (Down/Up) 515212 / 427
CRC Errors (Down/Up) 2079 / N/A
HEC Errors (Down/Up) N/A / 124747
Error Seconds (Local) 298
Do these stats make sense with the distances involved?
I think there may be some potential issues with the wiring of the house:
When I went to look at the extension wiring in the loft, it looked like a rats nest! I did spot a REN booster; would that have any effect?
I installed a BT iPlate last year, but when it was fitted, the modem could not sync with the DSLAM. The BT Tech Support guys were stumped at this, and they ran some tests and informed me that there was a 'fault' on the line. An OR engineer was sent out (not sure which type), and he ran an attenuation test (not sure if that's the correct name!) from the test point in the house to the exchange, and got a figure in the 50s (sorry, it was a long time ago and I didn't have the foresight to write it down!) he said that the tech support guys had a figure in the 70s, which is why he was called out. He said that as far as he was concerned, there wasn't a fault and left it at that. I didn't really chase the issue up, until now. The BT tech support people also weren't happy to hear that I wasn't using the HH2.
We seem to have always had an intermittent problem that when we receive an incoming phone call (when the phone starts ringing), the modem loses sync with the DSLAM. It seems to come and go. For example it's happened twice today, once in the morning and once late afternoon. There have been a good fifteen incoming calls (admittedly a few were when I was trying to provoke it!). Sometimes it happens with virtually every call, and sometimes we don't see it for a good month or two.
There is also a fair amount of background noise on the line if I try a silent line test.
I have switched to my old Netgear DG834Gv1, and spent the evening logging the line. Below is a bit from this evening. The dip in the SNR coincides with when I picked up the phone to make a call.
Is there any logging which I can do overnight/for a longer period of time? I have noticed that the HH2 does occaisonally lose sync with no apparent reason.
I guess the next thing to try is to plug the router and a phone in to the test point and see if any of the problems are also experienced there. The problem with the disconnection is that they don't happen consistently.
When we learnt that we were in a FTTC enabled area, we jumped at the chance. Because the BT speed estimator gave us 11Mbps, it meant that we couldn't sign up for infinity services, and their Total Broadband FTTC Option 3 cost a bomb, so we're switching to Plusnet. If we were actually getting a reliable 1Mbps service then we may not, but this is so slow that streaming anything is a no no. Don't even think about someone trying to download something while someone else tries to browse the web!
They are coming at the beginning of next week to install this (yeah, I wish I had found this forum a bit sooner!). My concern is that there may be a fault with the line somewhere other than in the house (if it is in the house, I guess it doesn't matter too much any more), which then might also affect the FTTC service. If this is the case, I don't know whether it can be looked at when FTTC is set up- from what I have read, a lot of problems can slip through their 'standard set up tests' (such as LTOK?)?
From what I have read in some of the other topics, I could try to guess some faults, but I think a little knowledge in this area is a
dangerous thing! I was hoping that some of you experts might be able to provide more of an insight in to what is going on!
Phew, sorry for the long post (and congrats if you made it this far ;)), I just wanted to get as much info as possible out there!
Thanks in advance,
Thomas
[attachment deleted by admin]
-
Hello limbo and welcome
Your line seems to be significantly under-performing. If the iPlate is still fitted I would remove it and remove the (ring) wire in terminal 3 of your master socket. Ensure your modem is connected directly to the master socket and try again.
You'll see from this link
http://www.kitz.co.uk/adsl/max_speed_calc.php
that Kitz's speed estimate is higher than you actually achieve.
It does appear to me that you have a high resistance fault on the line if you get a disturbance when you make a call.
Others may have more comments later
Kind regards,
Walter
[attachment deleted by admin]
-
I would second the above, but if it makes no difference then you should connect the router to the test socket and leave it there for long enough to establish whether you still get the same symptoms. It's the only way to be reasonably sure that your own wiring isn't the problem.
-
I agree with both Walter's and Eric's comments.
There definitely seems to be a fault in your copper pair. Whether it is your side of the NTE or the OR side is the first thing to determine. If you can clearly see where the OR D-side service cable reaches your home (underground or aerial) and are able to follow it to the NTE & then to all subsequent sockets, a clear set of photographs would be most beneficial to our understanding.
Without full information, remote diagnosis is fraught with errors and can result in an entirely inappropriate course of action being taken.
-
Hi everyone and thanks for your replies (and thanks Walter for the PM).
If the iPlate is still fitted I would remove it and remove the (ring) wire in terminal 3 of your master socket. Ensure your modem is connected directly to the master socket and try again.
You'll see from this link
When I fitted the iPlate, it prevented the modem from syncing with the DSLAM at all- hence it was a very short lived experiment!
-
I agree with both Walter's and Eric's comments.
There definitely seems to be a fault in your copper pair. Whether it is your side of the NTE or the OR side is the first thing to determine. If you can clearly see where the OR D-side service pair reach your home (underground or aerial) and are able to follow it to the NTE & then to all subsequent sockets, a clear set of photographs would be most beneficial to our understanding.
Without full information, remote diagnosis is fraught with errors and can result in an entirely inappropriate course of action being taken.
It's an underground cable, and I know where it comes in. I can take a picture of the incoming line and the master socket (with the cover taken off)- do you want pictures of all of the extension sockets? There are a surprisingly large number of them, and some of them got disconnected before I was around (I've not tried to figure out which ones are still connected) for ages.
-
I would second the above, but if it makes no difference then you should connect the router to the test socket and leave it there for long enough to establish whether you still get the same symptoms. It's the only way to be reasonably sure that your own wiring isn't the problem.
I am going to do this tomorrow when no one else is around! Which router is better for this kind of work? Do you think I should continue using the DG834Gv1, or use the HH2? I ask because I can't seem to get the attenuation figures from the DG834G (just SNR). This is probably me being a little silly, though.
I'll post data here as soon as it's available- presumably there should be an immediate difference in the SNR and/or attenuation?
-
I can't seem to get the attenuation figures from the DG834G (just SNR)
Sorry to clarify this, I can only see the SNR data in RouterStats- nothing on the line attenuation.
Thomas
-
It's an underground cable, and I know where it comes in. I can take a picture of the incoming line and the master socket (with the cover taken off)- do you want pictures of all of the extension sockets? There are a surprisingly large number of them, and some of them got disconnected before I was around (I've not tried to figure out which ones are still connected) for ages.
If you are quite sure that there is not a junction box anywhere before the NTE5/A, then a set of photographs of where (1) the service cable arises from the ground, (2) of its connection to the supply feed cable which enters your home and (3) the connection of the latter to the OR side of the NTE5/A should prove to be sufficient, for now.
If you also wish to include a photograph of the connection of the extension wiring to the customer's face plate at the NTE5/A, that might provide an indication of the standard of your extension wiring. :)
-
@Thomas -- If you would be willing to send me your postcode in a PM, I will look it up in a copy of the leaked BT Wholesale database file that I possess. Hopefully it will identify the PCP through which your line passes. Then all you will need to do is to walk around your neighbourhood and look for the correct numbered cabinet and its fibre companion. :)
-
Morning everyone,
I've taken some photos, and here are the results:
Outside the house. The cable which on the left is the one which goes to the main socket (and test point).
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2FDSC_0525.jpg&hash=e15b1f2856addbe92b5ebd610629e4ec54a9fc00)
Presumably there is a junction box in there? Did BT install those two extension points? There are two points around which are smaller than a standard single telephone socket/single power socket/network point/light switch (you know what I mean!). They also have the same old style T logo that the test point has. However I have just gone and tested the one socket (which looks like that) which is still left- it is dead. Looking on the outside, I would guess that someone rewired this but didn't remove the cables?
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2FDSC_0526.jpg&hash=df4ecc8b122e4b9e44db13375dc8733e34a5b9d0)
A closeup of that wiring: I hadn't spotted that before: is this bad?
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2FDSC_0532.jpg&hash=dd234948152869820a8b9b9b905c537a60ca5ee3)
On the inside:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2FDSC_0522.jpg&hash=37caf74a59a82b334b865e5b211736834210410c)
With a clseup of our internal wiring:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2FDSC_0523.jpg&hash=88b4b76920a19964ec32e11765f516f5bc16e30d)
With everything else removed, the quiet line test was certainly...quieter! It was not silent, though. How quiet should it be? I would describe the sound now like a quieter version of the pressurisation noise you get when you're on a plane.
Thanks,
Thomas
-
I also (as you can probably see) switched to the test socket last night.
I took some data in the wee hours of the morning:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2Fnightsnrrxtestpoint.gif&hash=a25b264ada213ee9da793deef63dff9cc6277de7)
and a little more:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2Fnightsnrrxtestpoint2.gif&hash=1e15a76d60647f92d2de9e37d6ce7df06584f76a)
and some stuff from a little earlier on today:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2Fmorningsnrrxtestpoint.gif&hash=1f015e59c5457521a9583fcac0dd1f6375abad96)
I put my PC to sleep (forgot to turn data logging off). I think this is where the line drawn down the graph is. I came back to find that according to RouterStats, the SNR had dropped to 18dB, from about 30. I don't think that the first drop to 0dB coincided with any incoming/outgoing phone calls.
I got very confused about this, and so I (perhaps stupidly) went to power cycle the router. Since then the connection has been very stable, sitting at 31dB with only 2 dips by about 1dB in the past hour or so.
After running some speed tests, I can say that the speeds on this line have not changed.
Thanks,
Thomas
-
Your Noise Margin is very erratic isn't it ?
On the Routerstat graphs you've posted so far it ranges from 7dB to 31dB ???
-
I don't know what's inside that grey box on the outside wall, but the wiring to it looks very amateurish, and I can't believe that BTOR would have left it in such a state. Perhaps someone else can identify it for us. If it's just an external junction box, then I think you need to get BT to regularise the wiring from there to the NTE5, and if it was the work of an unofficial person then I guess you'll be charged for that job.
The internal wiring also looks a mess (perhaps the work of the same person?). There seem to be wires connected to all six terminals in the NTE5 faceplate. The whole lot needs to be stripped out and done properly. This is a job you can do yourself - all you have to do is connect terminals 2 and 5 in the faceplate to the same terminals in the extensions, using a single twisted pair for the purpose. Conventionally you would use the blue/white - white/blue pair for this.
Until the wiring is sorted out it's not going to be possible to diagnose the performance problems.
-
I've just reviewed your photographs, Thomas. Oh dear, not very good at all. :no:
Unfortunately, as Eric has said, you will need to have OR to resolve that external "pig's ear". However as you will be having an engineer visiting to make a check and install the modem, it could all be resolved there and then. It really depends upon whether the visiting engineer is an ex-armed forces new-recruit or a time served CSE such as Mr Pag.
Stock up with chocolate biscuits, bacon (sandwiches, for the use of), tea and coffee. Then as soon as the engineer has arrived, show her/him the outside "folly" and say that in your opinion it does not look correct -- what does (s)he advise?
-
Hi everyone,
Thanks for your feedback.
I popped over to my next door neighbours and they let me test their broadband speed. For some reason the BT Speedtester was not working (and in fact on this connection it is just very slow). I ended up using speedtest.net on the same server as I do- they got 2.42 Mbps down and 0.37 Mbps up, with a 50ms ping. That sounds more reasonable!
I've attached yet another SNR graph in case you didn't have enough already! This captures a nice drop and then increase again.
Also, does anyone know why my IP profile for uploading is faster than for downloading (this does seem to be a strange side effect of the problem)?
Cheers,
Thomas
[attachment deleted by admin]
-
I don't know what's inside that grey box on the outside wall, but the wiring to it looks very amateurish, and I can't believe that BTOR would have left it in such a state. Perhaps someone else can identify it for us. If it's just an external junction box, then I think you need to get BT to regularise the wiring from there to the NTE5, and if it was the work of an unofficial person then I guess you'll be charged for that job.
The grey box is a standard Cover 101A and below it is a length of Capping 25. Inside the grey box should be gel-crimps connecting the active pair of the service cable (the black cable) to the feed-in cable (white).
In theory there should be a Connector Bend at the top of the service cable duct (visible in the paving slabs), then a length of Capping 25, all topped off by a Cover 101A. The hole should have been drilled through the wall from under the Cover 101A. As it currently exists, everything that could be wrong with that installation actually is! :(
-
As it currently exists, everything that could be wrong with that installation actually is! :(
Hi b*cat,
What I find surprising (not unhappy with him- I guess he was focussed with the attenuation data which he took) is that when the OR engineer came a year or two ago, he said that he was only looking at the test point to the exchange (no internal wiring- which is how OR operate). But he didn't spot any of these errors which you guys pointed out straight away.
I guess it's up to me to get the OR engineer on Monday on my side (with deployment of tea/coffee, biscuits and bacon butties!) to try and "clean up" the external point.
Stock up with chocolate biscuits, bacon (sandwiches, for the use of), tea and coffee. Then as soon as the engineer has arrived, show her/him the outside "folly" and say that in your opinion it does not look correct -- what does (s)he advise?
Hopefully the engineer won't feel like I pounced on them when they arrive! :-[
Does anyone know what the chances of them helping out are (guess as you say, it totally depends on the engineer)?
Cheers,
Thomas
-
Chances:
50% :shrug2: 50%
If I was the engineer tasked with your FTTC installation, I would:
(1) Externally -- Strip off the Cover & Capping, identify the three whitish cables present, remove the existing feed-in (white cable) replacing it with new, silicone seal it where it enters through the brickwork, make a nice u-bend drip loop, re-make the gel-crimped connections from the service cable to the new feed-in cable and then finally fit the correct Connector Bend, Capping & Cover working from the service cable duct, upwards.
(2) Internally -- Replace your existing NTE5/A with a new OR banded one. Check for POTS service and sync to the DSLAM at the test socket with my JDSU HST-3000C. Eat bacon sandwich. Drink mug of coffee or tea (depending if a morning or afternoon appointment). Discuss with you where you would like to have the modem sited, where you would prefer the router and where you have your computer. The modem would be wall mounted (highly recommended, to ensure efficient cooling), a SSFP would be fitted to the NTE5 and any necessary data cable deployed. The current 2x6 wires attached to your existing face plate would be left disconnected and tidily coiled at the bottom of the NTE5 backing box. The new face plate would be re-affixed to the SSFP. I would then check, again, the POTS service and the DSL signal with my JDSU. Assuming all is well, the modem would be connected and powered up. Presuming that you had tempted me with a chocolate biscuit, I would suggest that you now connect your ISP / CP supplied router, power it up and see if you can obtain access to the Internet.
Well, you did ask . . . ;)
-
Hi,
Thank you b*cat, I hope that the engineer has a soft spot for biscuits and bacon sandwiches!
I found out which PCP I am on, and where it was- it is the one which I thought was connected to the adjacent exchange- apparently not! If the cables go via the main road, I estimate a cable length of 750m. It's a rather long route, so if they cut across roads (the way the footpaths do), I reckon it's nearer 600m. If it took an even longer way round, we would be talking 800m. Thinking about it, I think the cable must come down the road, in order for it to be a sensible route. In a straight line it's 400m.
Assuming the line is in good working order, what speeds should I expect from (what I believe ought to be the length of the line) 750m?
Thanks,
Thomas
-
Assuming the line is in good working order, what speeds should I expect from (what I believe ought to be the length of the line) 750m?
Hi Thomas,
I don't wish to step on b*cat's paws, but if I may be so bold, I will just step in for a moment.
That looks like such a simple question that should have an even simpler answer.
20 pages into the other thread, we still do not have a definitive answer, or even a decent guesstimate.
Your pre-installation speed estimate is/was 11 Mb.
God only knows what it was based upon, & I would put a month's salary on him not being 100% sure.
BT can't/won't explain.
Plusnet say it is based upon line length, but then quote the length right from the exchange & then clarify it by saying it also takes other factors into account, but admit they don't know what the other factors are.
Near the end of May, my estimate from BT was that FTTC is not planned for my area within the next 6 months!
Plusnet's estimate was 14.6Mb.
At first I achieved actual downloads of 33Mb, probably syncing at around 35Mb.
My download speeds have been up & down like a yoyo for 2 months, currently around 20Mb, & for a while as low as 7 Mb.
Plusnet have claimed more than once that as current speeds are more than the originally estimated speed they can't/won't do anything about it, but please see my latest update in the other thread.
In other forums, some users have achieved 37-38Mb downloads over 600-650m.
You already appear to have some line issues that "hopefully" will become irrelevant once your broadband line comes from the nearby cabinet rather than all the way from the exchange.
Does that clearly answer your question? No, I thought not.
If you ever do manage to find a proper answer, please let us know & pass us the 6 winning numbers for the lottery while you are at it.
The only answer available at this time is - "it depends".
So, good luck with the installation, record the stats from the engineer's JDSU or other device & please post them on here for others to absorb.
Paul.
-
Assuming the line is in good working order, what speeds should I expect from (what I believe ought to be the length of the line) 750m?
Having dispatched a rat ( :tongue: nasty creatures), I drew its entrails with my especially sharp disembowelling claw and threw them up into the air. Once landed, I then studied them intently for 19.7 seconds and now I am able to make this prediction --
40 Mbps > downstream sync speed > 20 Mbps
I leave the rat remains for a passing bird of prey to tidy-up. :P
The best advice I can give, Thomas, is hope for the best but be prepared for the worst.
With regard to the length of your D-side copper, I would be tempted to assume twice the straight line length from your home to the fibre cabinet -- hence I'd work on the assumption of 800m (until told otherwise). :)
-
@ Paul,
Were you of a naval disposition the words following "depends" are usually "on the angle at the dangle". However as this is a family-friendly site so I shall not continue!
One of our major problems is that we are aware of a single constant "uplift" figure for all services from a particular PCP. It seems quite preposterous that such an approach is suggested when we all know that different D side lengths and line conditions can and do cause significant variations. Quad erat demonstrandum !
Kind regards,
Walter
-
Hello,
At Walter's suggestion that my old DG834Gv1 might be knackered, I've switched over to using the 2Wire.
Interestingly the DSL upload rate has increased (although it may have been the cut which caused the DSLAM to start syncing at a higher rate), but the download rate is staying where it is.
The Downstream SNR looks much lower than with the DG834G- at around 15dB, yet the speed has yet to increase. I notice that it is running on ADSL2 (I think)- does that have any adverse effects, or should I stick with it?
Thanks,
Thomas
[attachment deleted by admin]
-
Hello Limbo,
It does appear that your bRAS has stuck at a very low level as your maximum rates are actually above what you might normally expect according to the Kitz estimator.
Your 2Wire data does indeed show you are on an ADSL2+ service which, at your line distance, is probably unwise.
However as you are about to obtain a FTTC service it's probably better to wait for that installation rather than complicate matters with further enquiries.
Kind regards,
Walter
-
Hello Limbo,
It does appear that your bRAS has stuck at a very low level as your maximum rates are actually above what you might normally expect according to the Kitz estimator.
Your 2Wire data does indeed show you are on an ADSL2+ service which, at your line distance, is probably unwise.
However as you are about to obtain a FTTC service it's probably better to wait for that installation rather than complicate matters with further enquiries.
Kind regards,
Walter
Hi Walter,
Thank you for confirming this. I'm glad that there is potential on this line!
Does the modem calculate the "maximum" speed? It seems to have been changing from 4.2Mbps to 3.6Mbps. Currently it's sitting at 4Mbps.
I just power cycled the modem, and the upload speed has marginally increased to 1Mbps (from 976Mbps), but the download speed is still at 575Kbps. I wonder whether the ip profile might be "stuck" on this low speed, but seeing as there's less than 24 hours on this ADSL connection left, I don't mind!
When the engineer comes over tomorrow, I'll see how obliging he is with our external wiring! I'll take as much data as I can from him, and post them here once it's up!
Many thanks,
Thomas
-
Hi Limbo,
A good plan. If you are able to capture the full diagnostic data complete with the bit loading diagram that would be be useful ammunition as well. (Just in case you get into Bald Eagle mode ! )
Kind regards,
Walter
-
Hi Limbo,
A good plan. If you are able to capture the full diagnostic data complete with the bit loading diagram that would be be useful ammunition as well. (Just in case you get into Bald Eagle mode ! )
Kind regards,
Walter
Good morning everyone,
Well BT Openreach have now been and gone. The engineer (in his Superfast Fibre van!) wasn't an ex-army chap, but he specialises in installing and fault-finding FTTC.
The engineer turned me down on the offer of a bacon buttie :no:! I explained to him the problems we had been having. He then went off to the PCP to wire in the DSLAM. When he got back he said that in the cabinet one of the wires of our pair was broken and held together by the insulation, which when he touched snapped in half. He said that it may well have manifested itself as a HR fault. He seemed surprised that we hadn't heard any crackling on the line, but said that might explain a bit of the "white noise" which we had been hearing. He didn't seem to know the length of the line to the PCP, but said "I think you'll get faster speeds than 11Mbps- that's very conservative".
He took a look at the external wiring, and took the front face off. Seems that the two wires to the right simply pass through, and do not touch the incoming wire. He re-crimped all of the incoming wires- I think there used to be another line, as there were 4 incoming wires (did it so quickly that I didn't ask him to just remove the seemingly unused pair!). He didn't replace the wiring to the NTE, but tucked it all in to the Cover101A, so there are no bare pairs showing now. He also replaced the NTE with a new OR branded plate. He looked at the internal wiring and said "well that's all wrong!" and redid it properly for the new plate. Interestingly, he did wire the bell wire in.
He then got his JDSU out, and said that everything looked OK. He then let me take a picture (see attached). The JDSU reckons a line length of 0.9km (how does it estimate that?). Apparently PN don't pay OR for a 'managed install', so technically all he was meant to do was plug the modem in and run, but he wanted to check the line speeds as well.
All of the diagnostic data he took was on the JDSU- he got it out and checked that there was a reasonable speed. When I asked about bit loading (I may well have explained it wrong), he didn't seem to follow me. Lastly he got a LTOK, and that was that.
So this is what I am currently getting:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fwww.speedtest.net%2Fresult%2F1478517584.png&hash=393c5a97733924adb8d0bea8f698995c364874f1)
I would attach some BT Speedtester results, but I did one a little earlier (stupidly didn't take a SS of it) and apparently I need to wait an hour to do another one.
How come the IP profile is at 27Mbps (looking at the JDSU)- should it start at 40 and work its way down to a stable level, or am I misunderstanding something?
Sorry I couldn't get more data, I think he saw this as a very straight forward install and so didn't do much diagnostic stuff. I do hope the JDSU data is useful.
Kind Regards,
Thomas
[attachment deleted by admin]
-
Oh dear that photo of the JDSU is terrible! Here's an uncompressed version which hopefully will look a bit better:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fi1191.photobucket.com%2Falbums%2Fz476%2Flimbo8%2FIMG_1241.jpg&hash=0a0e92854b725b6e868da0752d0f72f1c2c26008)
-
I explained to him the problems we had been having. He then went off to the PCP to wire in the DSLAM. When he got back he said that in the cabinet one of the wires of our pair was broken and held together by the insulation, which when he touched snapped in half. He said that it may well have manifested itself as a HR fault. He seemed surprised that we hadn't heard any crackling on the line, but said that might explain a bit of the "white noise" which we had been hearing. He didn't seem to know the length of the line to the PCP, but said "I think you'll get faster speeds than 11Mbps- that's very conservative".
He then got his JDSU out, and said that everything looked OK. He then let me take a picture (see attached). The JDSU reckons a line length of 0.9km (how does it estimate that?). Apparently PN don't pay OR for a 'managed install', so technically all he was meant to do was plug the modem in and run, but he wanted to check the line speeds as well.
So this is what I am currently getting:
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fwww.speedtest.net%2Fresult%2F1478517584.png&hash=393c5a97733924adb8d0bea8f698995c364874f1)
I would attach some BT Speedtester results, but I did one a little earlier (stupidly didn't take a SS of it) and apparently I need to wait an hour to do another one.
How come the IP profile is at 27Mbps (looking at the JDSU)- should it start at 40 and work its way down to a stable level, or am I misunderstanding something?
Sorry I couldn't get more data, I think he saw this as a very straight forward install and so didn't do much diagnostic stuff. I do hope the JDSU data is useful.
Kind Regards,
Thomas
Well Thomas, you're not stuck in limbo any more then :no:
The engineer seemed to be quite helpul & obliging & hopefully your various line issues have now been permanently fixed.
I'm not sure about the bell wire though. Someone else may advise you to remove that???
It should take around 10 days or so for your speeds to stabilise.
Are you happy with the current speeds? They are a lot higher that your "meaningless" estimated speeds.
I'm really glad that you managed to take a photo of the JDSU showing the estimated line length. None of my visiting engineers have shown that display to me. More than one visiting engineer told me that the JDSU could not display that sort of detail when I asked them for it >:(
I will be using your photo as evidence (if you have no objection) when the next engineer vists me, hopefully during this week.
I believe that line length is estimated via the JDSU mainly based upon on the attenuation figure, but more knowledgeable people than I aren't really quite sure for VDSL2 purposes. It may well take other factors such as SNR levels into account.
VDSL2 as delivered by BT, known as Profile 8c, Annexe B has the downstream split across 2 frequency bands, the lower band is more or less the equivalent of ADSL2+ frequencies, & the higher band is used for VDSL2 higher frequencies.
It is thought that the attenuation as displayed on the engineers' JDSUs must be some sort of an average value for both bands.
Some other countries use higher frequencies, with more power, split across 3 bands.
Nobody appears to be quite sure what typical attenuations for a given line length for VDSL2 purposes should be yet.
It would probably depend whether it is all copper, or part aluminium cabling. Both have different attenuation values.
Due to your actual or estimated distance from the cabinet, it is very unlikely that 40 Mb would be delivered to your home.
Others with guesstimated line lengths of around 650m & a JDSU attenuation value of around 19dB or so have been achieving download speeds of around 37Mb, more or less the full whack available, less a bit for overheads.
The IP Profile & download speeds as shown in the BT speed tester & the engineer's JDSU apparently always appears a bit more pessimistic than actual download speeds as shown by other speed testers such as speedtest.net.
Your US & DS LIne Atten values are identical, which is interesting for me as there is a large difference between the two for my line, the US being much higher. The signal attenuation is probably the more important value though.
All I would suggest is that you regularly monitor your download speeds as reported by speedtest.net for consistency, along with regular BT speed test results (save the screenshots).
If nothing else, you will have a good record of your connection's capabilities if your speeds should start to plummet outside the 10 day training period. Your speeds may well even increase over the next few days.
EDIT: Just for curiosity, which version of the modem has BT supplied for you?
It should be displayed on a sticker underneath the modem, the firmware version ending in SP06 or SP10, & the hardware version may have a 2V or 2B sticker, also underneath.
Also please see the PM that I sent to you
Paul.
-
Hi Limbo,
I've not seen that VDSL2 emulate screen before either, so it is very valuable indeed. On NO account loose It !
VDSL is still a new technolog for me but I would certainly disconnect the bell wire just in case, but I'd wait for a time preferably around 14:00 to disconnect the modem.
When you do I suggest you turn the mains off at the power supply. Some modems have some last gasp logic so it's good practice, even though I don't know if that is implemented in your new modem.
It's a good idea to optimise your line as soon as you can and before the training period expires so you get the best possible stable connection.
Currently your bRAS is at 26726 k which looks as if it might have improved a bit since the JDSU reading, assuming that the same 82.5 % of sync rate applies to the VDSL connection.
EDIT I've just remembered from ADSL days that the JDSU instrument does not synchronise as fast as say a 2700 HGV so it's also possible that the same thing happens with VDSL.
@ RP with your experience, can you add anything to this piece please ?
Sorry this is all a bit empirical !
Kind regards,
Walter
-
@Walter -- Unfortunately Mr Pag left us yesterday and asked for his account to be deleted. :o :bye: If you send a PM to Eric, I'm sure he will fill in the details for you.
b*cat is rather unhappy with what has happened and also the way it happened. :'( RP was a friend and valuable source of technical information for us all. :(
-
Unfortunately Mr Pag left us yesterday and asked for his account to be deleted. :o :bye:
b*cat is rather unhappy with what has happened and also the way it happened. :'( RP was a friend and valuable source of technical information for us all. :(
Hi Folks,
I have not been a member of this forum for long, but I too am sad that RP has departed (for whatever the reason).
His general technical advice & feedback from "Johnny on the spot" has been partly my inspiration for keeping going with my own quest and I'm sure his departure will be a sad loss to the Kitz forum as a whole.
Paul.
-
Hear hear !
Kind regards to RP and many thanks for all the hours he has devoted to us.
Walter
-
Hear hear !
Kind regards to RP and many thanks for all the hours he has devoted to us.
Walter
While I didn't have any direct contact with RP, reading through threads, it was clear that he was a valuable contributor to these forums, and we will all miss his contributions :(
-
Well Thomas, you're not stuck in limbo any more then :no:
Absolutely not!
The engineer seemed to be quite helpul & obliging & hopefully your various line issues have now been permanently fixed.
I'm not sure about the bell wire though. Someone else may advise you to remove that???
What surprises me and I think surprised him, is that we never heard any crackling on the line (symptomatic of an HR fault- the broken wire in the cab).
It should take around 10 days or so for your speeds to stabilise.
Are you happy with the current speeds? They are a lot higher that your "meaningless" estimated speeds.
I guess for a line of my length it's probably as good as it's going to get- I count myself lucky that we are able to get FTTC. I do hope that it keeps up at these speeds, though.
I'm really glad that you managed to take a photo of the JDSU showing the estimated line length. None of my visiting engineers have shown that display to me. More than one visiting engineer told me that the JDSU could not display that sort of detail when I asked them for it >:(
I will be using your photo as evidence (if you have no objection) when the next engineer vists me, hopefully during this week.
I believe that line length is estimated via the JDSU mainly based upon on the attenuation figure, but more knowledgeable people than I aren't really quite sure for VDSL2 purposes. It may well take other factors such as SNR levels into account.
By all means show them the picture- perhaps you'll teach the engineers something!
Due to your actual or estimated distance from the cabinet, it is very unlikely that 40 Mb would be delivered to your home.
Others with guesstimated line lengths of around 650m & a JDSU attenuation value of around 19dB or so have been achieving download speeds of around 37Mb, more or less the full whack available, less a bit for overheads.
The IP Profile & download speeds as shown in the BT speed tester & the engineer's JDSU apparently always appears a bit more pessimistic than actual download speeds as shown by other speed testers such as speedtest.net.
If the line length is 900m or thereabouts, I guess these kinds of speeds make sense.
All I would suggest is that you regularly monitor your download speeds as reported by speedtest.net for consistency, along with regular BT speed test results (save the screenshots).
If nothing else, you will have a good record of your connection's capabilities if your speeds should start to plummet outside the 10 day training period. Your speeds may well even increase over the next few days.
I hope you're right- I've only had one disconnection so far- that was at 2.30 in the morning. Not entirely sure why it happened then (we were all fast asleep).
EDIT: Just for curiosity, which version of the modem has BT supplied for you?
It should be displayed on a sticker underneath the modem, the firmware version ending in SP06 or SP10, & the hardware version may have a 2V or 2B sticker, also underneath.
Also please see the PM that I sent to you
The modem is 2B HW, with SP10 SW.
I'll reply to your PM after this ;)
Thomas
-
Hi Limbo,
I've not seen that VDSL2 emulate screen before either, so it is very valuable indeed. On NO account loose It !
VDSL is still a new technolog for me but I would certainly disconnect the bell wire just in case, but I'd wait for a time preferably around 14:00 to disconnect the modem.
When you do I suggest you turn the mains off at the power supply. Some modems have some last gasp logic so it's good practice, even though I don't know if that is implemented in your new modem.
It's a good idea to optimise your line as soon as you can and before the training period expires so you get the best possible stable connection.
Currently your bRAS is at 26726 k which looks as if it might have improved a bit since the JDSU reading, assuming that the same 82.5 % of sync rate applies to the VDSL connection.
EDIT I've just remembered from ADSL days that the JDSU instrument does not synchronise as fast as say a 2700 HGV so it's also possible that the same thing happens with VDSL.
@ RP with your experience, can you add anything to this piece please ?
Sorry this is all a bit empirical !
Kind regards,
Walter
Hi Walter,
I won't lose that picture!
I haven't actually put the Faceplate back on yet, since I'm still messing about with the extension wiring in the loft (separate thread going to appear soon regarding the best way to do it!).
I've attached a BT speedtest screenshot from last night, and this morning, in case anyone is interested.
Oh and PN have definitely set the line speed at 37Mb- it says so on my account there!
Edit: So it seems that the one disconnection has reduced my IP Profile by a tiny bit
[attachment deleted by admin]
-
I'm really glad that you managed to take a photo of the JDSU showing the estimated line length. None of my visiting engineers have shown that display to me. More than one visiting engineer told me that the JDSU could not display that sort of detail when I asked them for it >:(
I will be using your photo as evidence (if you have no objection) when the next engineer vists me, hopefully during this week.
I believe that line length is estimated via the JDSU mainly based upon on the attenuation figure, but more knowledgeable people than I aren't really quite sure for VDSL2 purposes. It may well take other factors such as SNR levels into account.
Mr Eagle, I believe the JDSU measures the line length by sending out a small pulse (a ping) and timing how long it takes for the response (a pong) to appear. Electricity flows at a constant speed . . . so the distance is just (0.5 * C / (pong - ping)).
-
Will the Chinese have pangs, when they realise you're playing pomg-ping?:crazy: ;D
-
Will the Chinese have pangs, when they realise you're playing pong-ping?:crazy: ;D
Most definitely! :lol:
-
@ BKK,
Just to clarify (I hope), it must be an intelligent Ping to which the FTTC DSLAM recognises and thinks this pongs !
This is as opposed to the physical line tests the JDSU performs which can cover the entire line length back to the exchange.
Kind regards,
Walter
-
it must be an intelligent Ping to which the FTTC DSLAM recognises
Yes, that is my understanding of how the JDSU operates when making that measurement.