Re: slow Internet after bt line repair

[Tim Lamb]

In message , Tim Lamb writes

Following several days of phone line intermittency, I raised a line >fault with bt. After the usual threats about possible charges a lineman >promptly called the following day. > >Unfortunately I was on my way out to an appointment so wasn't able to >discuss what he found. We did talk about redundancy of *bell wires* but >I don't know if anything inside the house was altered. > >On my return, the phones were fine but the Internet connection running >at a rock solid 0.192Mb down and 0.356 Mb up! Normally I expect to get >4.0 to 6.0 Mb down and about 1/10th that up. > >dsl lamp on the router does not vary. I have tried various shut downs >to encourage re-training but no change. > >Advice from Demon help was that the router (speedtouch 0822E2), if left >on, would re-train over the next 72 hours which takes me to Monday:-( > >Any thoughts?

uk.d-i-y added to spread the enquiry base.

[Peter Crosland]

Repeatedly rebooting the router is just likely to make thing worse so don't do it! It may well be that the BT equipment has interpreted this as a fault and fixed the speed rather than allowing it to rise over time. Demon should be able to tell you if this has happened and reset it to allow the retraining process to restart. The time to retrain is likely to be at least three if not four days.

[Tim Lamb]

OK Peter. That's reassuring. His test equipment identified a fault at

65m from the home so just about where the overheads pass through some trees!

U Tube grandchildren videos are backing up...:-)

I'll give it to Tuesday and then chivvy Demon again.

>

[Martin Brown]

You should have been on about 2M after the repair unless the system had already negotiated itself down the spiral of death to sub 256k before the linesman arrived. I thought it negotiated up faster during a full retrain if the line capability improved markedly. Assuming 20CN Kitz reckons no more than 24 hours before you get the BRAS profile back to something approximately like what the line will support. eg

uk.telecom.broadband is the best place to ask about this. See also my thread in there about diurnal changes in SNR for a list of helpful tools and diagnostic tests. Routerstats lite and a German one than unfortunately my own modem(s) do not support. Reconnectin about an hour after local noon gets you the least MW interference from Europe.

Badly executed repair. Get them to do a line test again. TDR ought to find anything that has such a catastrophic effect on an ADSL connection.

I have a rural line that has been severely intermittent at times due to tree damage and various other mechanical failures on wires on poles.

I have never seen anything that low after a linesman repair. They usually seem to reset it at the exchange and it negotiates from something nominal like 2Mbps either upwards or downwards.

The only people I know who get

[Dave Liquorice]

So the sync speed between the modem and exchange is still crap, as reported by the modem not an online "speedtest"? If the line is now good that modem reported sync speed should be back to normal.

Monday:-(

Sync speed is only half the story. There is no buffering within the BT network so there is a mechansium that tells the ISP how fast a given line can be fed data, the BRAS rate. Line noise from faults, nearby thunderstorm, etc will cause the modem to lose sync an retrain. If this happens and the resultant sync speed is lower the BRAS will get knocked back. Once the line is working properly again, the BRAS will automatically recover but that can take up to 72 hrs.

The algorithum for this automatic recovery seems to have been tweaked such that a big difference between a stable sync speed and BRAS rate will get corrected quicker than a smaller one, perhaps within 12 hours. Trouble is it's also not unknown for this automatic correction to get locked out, your ISP will have to restart the 10 day training period to get it unlocked. My ISP has button on the line control pages to do that.

[The Natural Philosopher]

phone ISP and say 'iffy line fixed, please (get BT to) reset line'

[Tim Lamb]

Spiral of death eh! Could be. The line was flaky over several days before I was brave enough to call BT.

Interrogating a router sounds a bit technical for me. I'll wait until Monday afternoon and then ask Demon to check BT have done a reset.

Thanks

[Tim Lamb]

This is from slow loading and online speedtests. I am not clever enough to monitor the router.

Right. I'll ask on Monday. Thanks.

>

[Peter Crosland]

The problem is that if the repair was done by an engineer who is not broadband trained will not be able to do this. The ISP should be able to do it quite easily.

[Tim Lamb]

In message , Peter Crosland writes

Breaking news....

The line is now connecting at 4.24Mb/s down and 0.367Mb/s up. Curiously the up result displayed is higher than the dial readout throughout the test!

Thanks to all for advice and reassurance:-)