Excellent support again

Bill · Oct 28, 2009, 10:38:04

A while ago I moaned that BT had upped my target SNRM to 12db for no very good reason that I could see, and last night I finally got fed up with it and asked Simon if he could get it fixed...

Just after 10am today, another resync... 14745 Kbps at 6db, fastest I've ever seen on my line

IDNet not hanging about again!

Now to wait for the profile to catch up and see how stable it is...

Glenn · Oct 28, 2009, 11:08:44

,

Always good to hear positive experiences

Simon · Oct 28, 2009, 12:17:18

It certainly helps to balance out the negative ones! Thanks, Bill.

Ray · Oct 28, 2009, 12:52:05

That's good to hear, Bill.

Bill · Oct 28, 2009, 13:09:57

Sort of related question- I may need to do some r-arranging of the phone leads, what's the "safest" way to shut down a router without the DLM thinking it's a sync loss and getting upset?

psp83 · Oct 28, 2009, 14:25:46

Quote from: Bill on Oct 28, 2009, 13:09:57
Sort of related question- I may need to do some r-arranging of the phone leads, what's the "safest" way to shut down a router without the DLM thinking it's a sync loss and getting upset?

I normally turn off at the mains.. or if you have an on/off switch on the router, use that.

Simon · Oct 28, 2009, 14:26:20

Switching off power at the mains socket, I believe.

That's two of us.

Ray · Oct 28, 2009, 14:27:42

That's three!

Glenn · Oct 28, 2009, 14:49:02

I find at the fuse box is safest

I agree with the other chaps.

Bill · Oct 28, 2009, 14:49:29

Thanks all, that's what I thought... I believe the router sends a "last gasp" signal that it's about to shut down.

Just seems a pity that there isn't a way to do it in a more controlled fashion

davej99 · Oct 28, 2009, 17:19:11

Quote from: Bill on Oct 28, 2009, 13:09:57
Sort of related question- I may need to do some r-arranging of the phone leads, what's the "safest" way to shut down a router without the DLM thinking it's a sync loss and getting upset?

I do not know if it helps, but I "disconnect" (log off) in router admin and then powerdown. I also understand the router sends a last gasp "this is not loss of sync message" when the power is turned off. I do not restart the router for at least 5mins. I used to repeatedly "disconnect/connect" rather than reboot to try and find a better central, but this has not been neccessary with IDNET. This never caused problems, but rapid rebooting can. Taking the incoming lead out of a live router does look like loss of sync and is not a good idea. A storm here once led to many outages, but I did not see any inpact on sync and profile.

Rik · Oct 28, 2009, 17:48:42

The more controlled fashion, Bill, is to tie a piece of string round the RJ11 cable and gradually pull it tighter and tighter.

Bill · Oct 28, 2009, 18:08:41

Quote from: Rik on Oct 28, 2009, 17:48:42a piece of string

I'm sure BT must have some left over from what they used to connect my house to the exchange

Rik · Oct 28, 2009, 18:09:17

But is it properly wet?

Bill · Oct 28, 2009, 18:21:53

Quote from: Rik on Oct 28, 2009, 18:09:17

But is it properly wet?

Best quality BT tea from the OpenReach vans parked at the roadside

Naah, I'm being very unfair, I've had very little trouble with the line itself, and on the odd occasion I've called BT out for a problem (voice!!) the engineer has been knowledgeable and helpful and fixed it PDQ.

The annoying thing at the moment is that I'm only 60Kbps short of sync for a 13000 profile... do I risk a resync when the SNR drifts up a bit?

Decisions, decisions...

Rik · Oct 28, 2009, 18:25:22

It depends whether you want speed or stability, Bill. I'm 200k short of 4.5M, but the line stays stable. If I manage that extra bit with a morning re-sync, it will drop - usually the day after the profile lifts. OTOH, it might be worth a look at your wiring to see if you can find the extra speed.

Bill · Oct 28, 2009, 18:36:19

Quote from: Rik on Oct 28, 2009, 18:25:22
It depends whether you want speed or stability, Bill.

Both

It's not as daft as it sounds, my SNR only swings around by about 3-4db over 24 hours, so if I can resync at an opportune moment with a 6db target it should maintain it... IF the router can hang on at low SNRs, which I don't know. One I had (DG632??) would still hold sync at -2db...

QuoteOTOH, it might be worth a look at your wiring to see if you can find the extra speed.

To all intents and purposes I haven't got any internal wiring... router plugged into the master via a 2m cable and no extensions.

Rik · Oct 28, 2009, 18:38:20

I have one of the new 3db target margins, Bill, which BT seem to be rolling out slowly. I vary between 2.5 - 4.8db. It might just be worth trying a 2700 on your line...

Bill · Oct 28, 2009, 18:47:32

Quote from: Rik on Oct 28, 2009, 18:38:20the new 3db target margins

I didn't know about those, are BT finally beginning to show some sense? The concept of target SNRs is ridiculous, just let the damn thing sync as fast as it can and resync when it has to. In time it will settle at the highest speed the line can reliably maintain anyway.

And as for profiles... ditching them would be the best way to help smaller ISPs like IDNet losing custom to the big boys who can afford to invest in LLU...

Rant over

I'll see how things go before trying a new router. I like the 3Com and it wasn't cheap...

Rik · Oct 28, 2009, 18:48:50

I'm sure we could come up with a loaner if you want to try one.

Bill · Oct 28, 2009, 18:53:26

The offer's appreciated, thanks.

But I'll probably buy one if I decide to try it, the only spare router I've got is non-wireless. It was OK at the time, but what with AppleTV, Airport Express, a PS3 and assorted laptops I'd miss that wireless link!

Rik · Oct 28, 2009, 19:16:21

You should be able to get one for around £15 delivered, Bill.

Sebby · Oct 29, 2009, 15:51:02

Good news, Bill.

Tacitus · Oct 30, 2009, 09:15:59

Quote from: Bill on Oct 28, 2009, 14:49:29
Thanks all, that's what I thought... I believe the router sends a "last gasp" signal that it's about to shut down.

"Last Gasp" may be present on some routers but it is not necessarily enabled. It's present on the Draytek 2800s and some of the Zyxel models, but it's not enabled out of the box on either of them.

Other makes/models may vary.

Glenn · Oct 30, 2009, 11:48:05

I would have thought the best way is, if you have access is to tell the router to reboot, as it powers down, turn it off. It could possible cause corruption though.

Bill · Oct 30, 2009, 11:56:52

Well, after almost exactly 48 hours (suspicious in itself) of rock steady sync it's shoved me straight back up to a 12db margin

Email has been sent to support....

Rik · Oct 30, 2009, 12:07:12

BT's DLM acts like that if it thinks the line unstable, Bill.

Bill · Oct 30, 2009, 12:41:44

Agreed, but if it defines unstable as one resync in 48 hours then it needs a new dictionary...

I think it just as likely that the MSAN decided, for some reason, to simply change my targt SNRM, which seems to force a re-sync from the exchange end. It's what happened the first time it went to 12db from 9db, then the forced change back to 6db, then the latest to 12db again.

In each (unforced) case there was no obvious reason from my end for a resync to occur, the line had been rock steady

And that 48 hour period, to within a minute, is a bit much of a coincidence imo.

Rik · Oct 30, 2009, 12:46:49

It also looks at the error count, Bill.

Bill · Oct 30, 2009, 13:04:12

Agreed, but something has changed... why did it go straight from 6db to 12db, when previously it had sat happily at 9db for months on end, even maintaining speed over the occasional resync (some auto, some manual) and a 9-digit FEC count that actually rolled over?

(HEC errors were near zero and even CRC errors weren't high.)

Rhetorical question, btw

My own opinion (tfh firmly in position) is that BT have found a sneaky way to reduce the bandwidth they have to supply...

Rik · Oct 30, 2009, 13:06:44

Once a higher target NM has been used, Bill, it seems to go straight to it if it deems it necessary. However, BT are testing new DLM software, and I'm on it. It allows my line to sync at 3db, with the extra speed that goes with that. IDNet can also make subtle stability changes which don't have such a big impact, so a word might help.

Bill · Oct 30, 2009, 14:14:42

Had a word with Simon via email and it seems that, as you thought, the MSAN isn't happy with my error rate... damned thing, it wasn't bothering me

So now it's daily noting of the error counts as I make one change at a time to see if I can reduce them... hours of endless fun

Rik · Oct 30, 2009, 15:23:10

Remember, Max was even more painful when it launched...

Sebby · Oct 30, 2009, 17:33:49

Some may say it was painful to the max...

Rik · Oct 30, 2009, 18:08:55

And they'd be right.

JohnH · Oct 31, 2009, 13:30:59

Quote from: Rik on Oct 30, 2009, 13:06:44
However, BT are testing new DLM software, and I'm on it. It allows my line to sync at 3db, with the extra speed that goes with that.

Are they just testing in certain areas, Rik?

John

Rik · Oct 31, 2009, 13:32:27

It appears so. I'm in the lucky area, possibly because it's based on the MK node?

Glenn · Oct 31, 2009, 13:34:00

And I believe at your local exchange too, how much have you paid them?

Rik · Oct 31, 2009, 16:08:51

An email to Ian Livingstone.