just got FTTC this morning

Plugged My own router in (TG789) and this is what it tell me. 20,000 up , with snr 15.3 and 79.987, with 8.5 snr down. well pleased with that

WOW!! If only I could get close to my max (I get 14 mbps approx. on the up to 20 mbps service)
Would be interested if your speed remains the same after a few weeks?

In reply to a post by aavid60:

Plugged My own router in (TG789) and this is what it tell me. 20,000 up , with snr 15.3 and 79.987, with 8.5 snr down. well pleased with that

Don't muck about with disconnecting the router as the OR DLM can suddenly drop you 10meg and stick an interleave on of 8ms or more.

Strangely enough I managed to get back onto 80/20 with fastpath once I put the router on a UPS as we have had a serious problem with our local power supply.

There haven't been many (or even any) reports of a DLM intervention because of power-cycling the modem.

The power-cycling advice has carried over from ADSL days, and so certainly may hold. However, it just doesn't seem to happen. I've had a couple of times where I have done quite a number of power cycles, knowing what I could cause... but not a dicky bird.

VDSL2 certainly supports the "dying gasp" indication, so the cabinet can certainly be informed that a drop of sync is related to a power outage. Whether it happens in practice with any particular modem, or whether the DLM process takes note, can't be confirmed with certainty.

All-in-all, still a question mark. But worth treating as a serious issue.

There haven't been many (or even any) reports of a DLM intervention because of power-cycling the modem.
There are quite a few reports on the BT forums.
Of course, it is always difficult to judge the reliability of such reports as there are always so many factors going on at once.
I think that there are enough consistent reports to treat it as a serious possibility, probably a probability.

Ta. Always good to know whether we should really treat it as a serious possibility.

In reply to a post by undecidedadrian:

Don't muck about with disconnecting the router as the OR DLM can suddenly drop you 10meg and stick an interleave on of 8ms or more.

Disconnecting a router will have NO effect on the DLM. Disconnecting a Modem may have an effect.

@WWWombat: Normally I don't care, as I'm lucky enough to have had a decent connection for months, so no desire to reboot either modem or router except very occasionally.

By chance, I have just been playing with modem cable ( http://forums.thinkbroadband.com/fibre/f/4232837-bto... ). If it had worked well it would have been a single break in connection, but I have issues. I'm having to decide for myself how much fiddling to do to see if I can improve things, or if the fiddling will just itself cause extra issues.

Edited by StephenTodd (Fri 26-Apr-13 16:10:42)

In reply to a post by MHC:

Disconnecting a router will have NO effect on the DLM. Disconnecting a Modem may have an effect.

Normally true for Openreach VDSL2/FTTC, but in this case the OP plugged in his own router, which happens to include the VDSL2 modem too (ie a single box solution).

I know what you mean.

My first FTTC line went straight to FEC/interleaving (well, after 48 hours, twice), so I tried a few line fixes to see if I made any improvements. That meant quite a few disconnections within a day, on a couple of occasions, but I figured I would do the experiment anyway. But nada - not a peep from DLM.

It left me at exactly that speed for months, until the cabinet was converted to the 17a profile.

The only significant errors I had were early on due to star wiring.
DLM was absolutely right to lower my speed in that case, it was nothing to do with any modem resets.
Maybe I'll risk it and do a few extra experiments now. Line speed absolutely fine, I would like to reduce my interleaving.

I think the only time one needs to be really careful on power cycles is when trying to recover to a fast path profile, otherwise I think one a day at least is pretty safe to do.

In reply to a post by WWWombat:

In reply to a post by MHC:

Disconnecting a router will have NO effect on the DLM. Disconnecting a Modem may have an effect.

Normally true for Openreach VDSL2/FTTC, but in this case the OP plugged in his own router, which happens to include the VDSL2 modem too (ie a single box solution).

So, he connected a modem.

Well the fact we have had a serious local power supply issue which has resulted in 4 full outages in 4 months and a very dirty power supply with over voltages and brownouts and it had got so bad that the interleave was flopping around between 8ms and 64ms and my connection speed was dropped from 80 to just under 70 meg.

Stick the modem/router onto the UPS I have just bought and now the DLM over a couple of stages has returned the 80/20 with fastpath and even the FEC errors have dropped by 90% to what I am used to.

Now this may be due to the poor HT supply and whatever problem our sub station is having but the modem or modem/router combinations seem to be affected by power quality and disconnects.

That's an impressive result, given such a dire starting point.

How did you get the two figures of 8ms-64ms? Was that changes to times in a ping command, a TBB BQM, or readings from the modem's statistics?

In reply to a post by aavid60:

Plugged My own router in (TG789) ...

Where did you purchase the TG789 from? How do you rate it?

readings direct from my Draytek 2750n. The "Actual delay" field is the interleave.

According to UK power networks when then have sent me yet another cheque for the ongoing problems they are now claiming that there has been 3 faults over two high tension cables serving the area.

Currently they are now combing the area looking for more faults as 4 power cuts in a year mean that they have to pay everybody affected and each power outage after this means more compensation.

I got it from DSLSOURCE.CO.UK . It was £84 but I see it is now £100. I think it is still good value for what it does and would recommend it. it does everything it says on the can and VOIP over two lines as well. Half the price of Draytek.
It was also fairly easy to configure for vdsl2.