In reply to a post by mr_bean:

It's possible to get rather higher and still have a usable link.

It's not me you have to convince, it's BT's DLM

if you're getting few errors then FEC is a waste of bandwidth

Of course it is, you don't need error correction if you're not getting many errors. But if you are, it's a distinct advantage.

It's not me you have to convince, it's BT's DLM

In my case it's C&W LLU (Demon).

Interestingly my default SNRM has drifted down from 15dB after a particularly bad spell (result of a dodgy modem lead) to 9dB so C&W must apply some sort of monitoring - possibly it looks a stable length of sync (as I said I've currently been synced for 33 days without a break) more than error rate.

However if the OP can get hold of and use a Netgear DG834v4 then the initial SNRM can be tweaked to whatever you want so it's relatively easy to ignore BT's DLM.

Of course it is, you don't need error correction if you're not getting many errors. But if you are, it's a distinct advantage

Very true - I'd probably have to run somewhere around 1-1.5Mbps otherwise.

In reply to a post by mr_bean:

so it's relatively easy to ignore BT's DLM.

That's unlikely to be true.

I didn't think many ISPs got that done. Pretty pointless anyway if the underlying problem isn't fixed because the DLM will just slowly push it back up.

Tweakable routers allow you to override the margin set by the DSLAM so in effect you can ignore BT's settings by manually overriding them.

In reply to a post by kwikbreaks:

Tweakable routers allow you to override the margin set by the DSLAM so in effect you can ignore BT's settings by manually overriding them.

BatBoy being BatBoy I think you should read a little more into what he said .

It is easy to override the DLM in the short-term. But if the line is unstable in the first place, which this one may still be, then the result could be disastrous. If the DLM's hiked settings do not stabilise the line, due to user tweaking that it will not take into account, then it will choose even more restrictive settings.

Hence in this case it is not easy to ignore the DLM.

Its my extension that has become damaged
So have got myself 2 wireless network cards and will stick the router at the adsl nation faceplate
Then once the errors have shown to stop being as bad, will tweak the snr until bt DLM kicks in to lower it or [censored] off to LLU

defeats the purpose of interleaving

Hence in this case it is not easy to ignore the DLM.

I'm with BatBoy on this - the DLM, or at least the initial SNRM can be ignored with the right router - even if it winds up at 15dB.

You are correct, of course, in that if the DLM is pushing the target margin for a reason then that underlying reason may well bite you anyway - just because one can ignore the DLM in this regard doesn't always make it wise to do so.

However it sounds like iwish has identified the root cause of his problem so a bit of judicious SNRM tweaking will get him back to sensible figures/sync speeds in minutes rather than the weeks which it will take DLM to go from 12dB to 6dB

In reply to a post by mr_bean:

a bit of judicious SNRM tweaking

The operative word there is "judicious"... if the DLM becomes sufficiently irritated with a non-decreasing error rate it's quite capable of putting you on a banded profile, and there's no tweak that will get around that.

I know, I've been there