When should I see a speed increase?

Telephone cables outside in the road were severed last week, but I retained an ADSL connection albeit about 40 times slower than normal! BT repaired the connection yesterday morning.

I understand that the connection has to go through a retraining period of upto 72 hours, so line speed will be slow to start with. Currently I have a DS of about 120 Kbps. This has not changed at all since yesterday (10:00) when the repair was effected. US has consistently run throughout at 382Kbps, which is the normally expected level here.

Should I be expecting to see a gradual speed increase after nearly 24 hours, or is it normal for it continue at this low rate then suddenly jump up? Previously I've had a speed of 4 to 6Mbps...

Have you restarted your router since the repair?

It's your IP Profile you are referring to.
This will increase over time (up to 5 days but could be much quicker in your case) as long as you have reconnected at your normal speed (sync) and maintain it.

Lots of info on IP Profile and line stats on TBB...

Thanks for the reply. Yes, switched the router completely off for about 5 minutes after the line was restored.

I have checked speed again this evening, and if anything it is marginally slower - now showing 110Kbps.

I had hoped it would have shown some sort of speed increase by now, but I guess I'll have to suffer this until the 5 days is up, and then it'll suddenly magically whizz up to 4 or 5Mbps.

Here's hoping...

Have you checked that you are syncing at the rates you used to have before the line problem?

See http://www.dslzoneuk.net/adsl_line_stats.php

The speed figures are these from speed tests or from looking at the data in your ADSL modem?

If speedtests they'll take 1 to 5 days to improve, if from the modem if the line is any better they should have improved as soon as you switched if off/on.

If no idea how to get the numbers from your ADSL modem look at http://www.kitz.co.uk/adsl/frogstats.php

Current DS sync rate as shown in router/modem stats is 6400 which is slightly lower than previously. DS margin is slightly higher than before at 11dB, and DS Attn remains the same.

I am using www.speedtest.bbmax.co.uk for checking actual line speed - this is giving me the DS figure of 110Kbps. Thinkbroadband's test figure is virtually the same. There is no improvement this morning incidentally.

I'm using a Solwise SAR-600ER router which has so far given good results. I have no reason to suppose it's faulty. If I disconnect it now and try a different router, presumably I would be back to square-one re the training period if it makes no difference speed-wise?

Quote: "If speedtests they'll take 1 to 5 days to improve." Would I expect to see a gradual improvement over the time period, or a sudden leap upwards?

The change in profile should be in one fell swoop. As long as your router maintains the high sync there is no reason to change it (conversely neither will it do any harm if you do try a different router).

The afternoon of Thursday 20th saw my speed back up to 5.5Mbps. It maintained this speed until 18:55 today (Saturday) when it suddenly dropped out. DSL signal still present, and router showed I was still logged onto the Radius server, but no Internet available. Rebooted router and Internet connection restored. However, I am now back to a cr*p speed again, and have to suffer yet another 72 hour wait.

What causes the DS Rate (as quoted in the router stats) to vary? Thursday afternoon with the 5.5Mbps line speed, the router stated 6400Kbps. When I checked it at the point it failed this evening the router reported it as 2014Kbps. After rebooting the router (and connection re-established again) it stated 7424Kbps, which was confirmed by the BT speed checker. Now I see the router shows it as having dropped to 6880Kbps.

By my reckoning, the line dropped out for no more than 15 minutes before I rebooted the router. How long does the line have to be dropped before BT slash the IP Profile? 5 minutes, 2 minutes or what? On the face of it, it seems ridiculous that such a short break has such a major effect on the Profile. Presumably if I hadn't spotted it quickly, it would have been down to dialup speeds by now...

I'm afraid any drop in sync seems to immediately trigger a drop to the appropriate profile, there is no lee-way at all as far as I know.

Electromagnetic interference on the line (noise) will have caused your loss of sync. Unfortunately that noise could have happened anywhere along the route of your line to the exchange. Is there any discernible pattern which might give a clue to the noise origin?

No pattern as yet. The first problem (last week) was down to a complete loss of voice circuit, but ADSL hung on at approx 100Kbps with a return path through ground (earth). At least, that's my theory. The second problem this evening came out of the blue, with no identifiable reason. No mains power cuts, no discernable glitches, no lightning strikes, etc. Voice circuit remained good throughout.

The router and switches run through a UPS and two separate mains filters.

I am in a rural area and not usually prone to electrical interference. Certainly none was apparent at this location, as I was listening on a sensitive radio receiver which has a big wire aerial plugged into it. Whilst 3.7 MHz is higher than frequencies used by ADSL, I believe my receiver would have detected anything untoward locally. I would obviously not be able to detect electrical noise close to the exchange, unless it was extremely severe. I can, for example, detect a pulsed electric fence which is about half a mile away!

You said, "any drop in sync seems to immediately trigger a drop to the appropriate profile". So are you saying that literally pulling the modem lead out for a few seconds to change a filter, or re-plug the cable into the NTE5 test socket will cause the Profile to be reduced? I'm not trying to be "picky" here, I just want to try and understand what the practical limits are...