Line stats check please

Duke

Duke

Duke

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Joined
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Hi all,

Got someone having problems with Virgin ADSL (urgh, I know). They were connected fine for years until Virgin contacted them to lower their price, since then the connection has been all over the place. It looks like they've made some change at the exchange or their end?

How are these line stats?

16280417.jpg


This is connected into the test socket in the master socket. When connected into just the master socket, the connection speed drops to 2mbit which is a large drop :confused: but they are not getting near that anyway. Two speed test sites give 0.1mbit speed which is confirmed by downloading a file from BY FTP at 15-20k/s. However at other times the speed goes up to about 1mbit.

I've suggested to move to another ISP, which he is happy to (and cheaper), but wanted to check if its a line issue which will still happen on any ISP.

They don't have any LLU services at the exchange, as its only in a village with 1000 people connected.

Thanks
 
Bit of an update with this one. They changed ISP to Plusnet who were far cheaper than Virgin. BT have come out as I spotted some of the cabling outside was getting weathered so they fixed that and checked all the wiring inside and put a new wall socket on. Updated line stats are below.

50701719.jpg


Ignore the fact the downstream has dropped as that was on the test socket before.

The same issue exists unfortunately. Uploading is fine but downloading is very slow, as in under 20k/s which is confirmed on speed tests giving about 100kbps.

Going to read up if Plusnet have a particular issue but its still the same as Virgin, so could be exchange issue?
 
Locky said:
That's worse than Virgin, the downspeed has dropped and so has the SNR you are getting almost half the speed and a lower noise margin
Something is still not right with the connection mate.
Click to expand...

Yeah did mention in my post to ignore the line speed as the original was on the test socket which still has the same 'cap' issue. The speed hasn't changed on the socket they use (still same issue on both sockets and test socket).
 
swbroadband said:
However, from the information you've already supplied - it does seem like traffic management may be the main culprit. What did the BT test return?
Click to expand...

Its not my line but will get them to drop you a quick email, ta. Not sure what BT test you mean? They have been out to do some physical work but thats all I think.


edit: will run the test later, ta
 
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Test result below. The IP Profile is obviously wrong but is that auto set or put on by the ISP?

96913725.jpg
 
Thanks for the info and your email. They used to have one of those awful USB Modems (which was naturally turned off each night) but I put in a new Netgear DG834 a few weeks ago and told them to leave it on all the time.

I put new filters on yesterday and cycled the modem, so its been on for just over 24 hours.

I had hoped it was the dodgy wiring outside causing the line speed to drop and that it would pick up again over a few days of stability but that hasn't happened.
 
Bit of an update. It seems the line is being re-profiled as the connection speed in the router has dropped a lot and the line stats have changed (are they looking better?).

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I did the last reset of the modem a day earlier than I thought, so you can see the uptime of the router is 43 hours but the line has been connected for just 18 hours.

I've asked the owner to note the down/up speeds each morning for the next couple of days and let me know.
 
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ncjok said:
The downstream target noise margin has been significantly increased, probably in an attempt to confer greater connection stability, and the upstream noise margin has dropped, probably as a result of ongoing interference. As a result, downstream sync has gone from 4576 -> 2752 -> 480 kbps and upstream sync from 448 -> 384 kbps. The answer is no.

What we've covered:
  • Interference / connection instability effect changes to the noise margins.
  • Target and modem-reported noise margins affect the sync rate.
  • Sync rate affects the IP profile.
  • IP Profile limits the 'speed' you see, e.g. downloads, speed tests.
  • 4576 kbps sync with 15-20 kB/s download speed with some periods of "up to about 1 mbit" connected to the test socket on 29-Apr-10.
  • 2752 kbps sync and <20 kB/s download speed connected to the master socket on 23-Jun-10, 09:16.
  • 480 kbps sync with 135 kbps IP Profile on 23-Jun-10, 17:26.
This could suggest that the test socket scenario on Virgin, while displaying a reasonable sync rate, was subject to traffic shaping or congestion for the most part as you mentioned increased speeds were noted at other times of the day.

Migrate to Plusnet, remove the modem from the test socket and the sync rate dropped significantly. You need to identify the reason for this, e.g. ring wire, unfiltered telephones on extensions, sky box, cordless telephones...

Most recently the connection appears to be subject to a lot of noise and the modem is sync'ing at a terribly low rate. This could just be a continuation of a problem relating to a suggestion in my previous paragraph or, given that you've tried a different device and microfilter, a line fault external to the household or something attributable to random electrical noise.

In addition to troubleshooting the test socket / master socket issue you should consider monitoring the connection throughout the day rather than just noting the sync rates each morning. Use RouterStats to follow the noise margins and maybe DMT v.8.07 for a look at SNR as a function of frequency.
Click to expand...
Thanks for the post.

Just to clarify a few things about the sockets. They have three sockets. One in the kitchen which is the master socket and had the test socket behind it. This doesn't have a phone connected to it. There are two other sockets; one in the living room which has a phone connected and the second in the office room which has just the ADSL router on it. So its quite a simple set up with just two filters required. They don't have Skyv or fax machine etc.

The speed on the office line used to be about 1500k and was 2500k on the master socket and 4500k on the test socket behind it. All of them still had the 'cap' issue.

Since then, BT have come out as where the line comes in on the wall (via telegraph pole) it has a bunch of the small cables sticking out of the box, so I advised this was probably causing the slight crackling on the line and wasn't helping the ADSL issue. BT have put a new box up there and it looks new now and have removed the kitchen socket entirely (as they just had new kitchen put in and don't need it there) so apparently the master socket is somewhere upstairs in the roof or something. The connection speed at the office increased a little to 2500k which seemed about right as BT said he was losing a bit of speed due to the internal wiring, which they resolved.

As mentioned before, they were using a USB Modem which would have been off each night and mixed with the slightly dodgy line, would make sense for the low profile set.

The odd thing is this has been corrected at least a week or two ago but the profile issue still exists.

I only had the router on the test socket for an hour or so but am sure the internal wiring shouldn't be a problem.

I'll give it a couple of days as the profile and connection speed has changed in the last day, to see if it now resolves itself.

Would it be worth while removing the bell wire from the office socket later on?
 
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Thanks for the post. I always put the router in the master socket where possible but in this instance the kitchen wasn't appropriate and loft isn't easy to get to and would need wireless kit. I haven't got them to do the bt speed checker today but will do on Monday to see if it's resolved or not.
 
Right am just here now.

The connection speed increased each day; 480 - 992 - 2624 - 1920 but dropped back down today to under 200. The IP profile was still the same the whole time so they didn't actually 'get' the increased speed.

I've just removed the bell wire from the socket the ADSL is on, and will do the other socket and will check the master one shortly.

I noticed the connection time was about 11 hours on arrival, is it normal for it to disconnect whilst the IP profile is changing? Or could that be causing the issue?

I just rebooted the router after removing the ring wire and it jumped back up to 2400k but obviously still same profile for now at least.

Couple of screenshots below of before and after ring wire removal/reboot.

beforeringwire.jpg


afterringwireandreboot.jpg
 
Yep I had a good look at the wiring at the master socket, which BT relocated into the roof.

It basically just splits into two, going to both sockets downstairs. I took the bell wire off this socket which would have been easier to start with :p

The speed went up as pictured below, which was the same speed when I had it in the test socket a month ago, but only had it in there for an hour.

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I've asked them to again leave it and note down the down/up and IP Profile for the next day or two.
 
Sync rate is still about 4000 but the IP Profile hasn't increased from 135k. What is the next course of action - contact Plusnet I take it?
 
Quick update - the IP profile is sat at ~1700 now, so all working again :) Not sure why it took so long for it to change but glad its going. It may improve further as the line should do 3mbit but for now that is great.

Thanks to all those that helped :)
 
Well the IP profile dropped again a couple of week ago on this one. Spoke to Plusnet and got things moving a bit more now. They said the line keeps disconnecting for a split second every day or so, hence the profile dropping. They are hopefully getting an engineer out to the exchange soon.
 
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