sync :/

Hi,

I am on a BTWholesale DSLMax service.

The first day the service went live my stats were:

Attenuation: 59db
SNR Margin: varied between 6 and 1db
Sync down: 2880kbps
Sync up: 448kbps

despite the noise margin going to 1db, the sync never dropped, at one point there was an uptime of 48 hours. Despite the constant sync, my snr margin crept up to 15db and as a result the sync rate is currently a rubbishy 1440kbps (with a router reported SNR margin of 13.5db)

I have tried both a Netgear DG834G and a Speedtouch 780 and there is no noticable difference in sync rate between the two.

The router is connected via a short RJ11 lead directly to a "dangly" microfilter, which is plugged into the NTE5 test socket. The phone socket is an NTE5 with the old "pied piper" bt logo.

My two questions, to which I'd be grateful for all replies are:-

Is there any way my SNR margin will return to 6db? I have tried using DMT however it doesnt like my service provider supplied DG834 (actually its model number is DG834GSP which means the firmware is locked down by the service provider) and it also hates my Speedtouch 780. Bah.

2880kbps for a longline with an attenuation of 59-62db is reasonable amirite?

Thanks,
Grek.

About a 3Mbps sync is average for a 59dB attenuation.

Your problem may be that your line is noisier than average which will lead to the automated systems pushing up your target SNR margin.

The automated systems will drop the target SNR margin by 3dB for every 2 weeks of stability.

Welcome to thinkbroadband.

About a 3Mbps sync is average for a 59dB attenuation.

I'd personally put that figure at the high end of the scale.

In reply to a post by john2007:

The automated systems will drop the target SNR margin by 3dB for every 2 weeks of stability.

Provided the error rates are within BT's limits, and with a 59dB line, I don't see that happening.
Best case might be an automatic drop to 12dB (or possibly 9dB) before the error rates start creaping up again.
And, if the user on on one of BT's antiquated Alcatel DSLAMs, I don't see it happening at all; they tend to rise to 15dB, then stick there.
Mine even went though the 14 day motions - resyncing at exactly 14 days, as if the system was trying to set the margin back to 12dB - but stayed at 15dB.
It's almost as if there's a fault with the code, or the Alcatel DSLAMs ignore the automatic drop requests.
My parent's one is still stuck at 15dB, even though it's showing a WAN uptime of about 5 weeks, and has almost no errors at all.

Fortunately, for BT, my parents aren't too worried about speed, so they're resisting my attempts at getting them to dump BT and go for BE or O2.
This could explain BT's resistance to changing target margins. If people we're so keen to stick with the rubbish speeds caused by this little bit of BT tinkering (and they all migrated to LLU), BT would be forced to change their ways (as they'd lose too many customers).
A big corporate dinosaur (such as BT, British Gas, etc.) only keep most of their customers because of apathy.

True, I should have said "are meant to" rather then "will" and have expanded on what "stability" actually seems to mean.

In reply to a post by john2007:

and have expanded on what "stability" actually seems to mean.

It's a shame BT won't tell anyone .