Noise noise noise!

I recently asked my ISP - Xilo to drop my interleaving as I want low pings.

My ping to bbc is 11/12ms which is brilliant but I am losing speed - massively.

My line is quite long - currently 50db attenuation although it used to be 45db and has crept up over the last couple of years.

I used to be able to sync at over 7Mb during the day and hold onto a 5696kbps sync for weeks.

Something is hammering my line with noise at night and I am desperate to find out what is doing it.

Looking at router stats light the line sits happily at 5696kbps up until around 10-10:30 and then for no apparent reason just drops. No sign of noise just a dive in the graph and it resyncs at around 5200.

It used to be able to hold onto 5200 for a few weeks (couple of months ago) but recently the line will drop - then resync around 50-100kbps lower and continue to do this, alerting DLM which has now completely destroyed any hope of getting a decent sync.

The router is now sitting at around 4100kbps, the SNR is 12db and in all honesty this isn't acceptable - pathetic really considering I know what the line is capable of.

I have an ADSL nation faceplate filter, a Netgear DG834GT running on the latest DGTeam firmware and I have tried an AM radio running at 600khz and nothing is audiable.

I am considering tripping the power off at home at 10pm and running a UPS on the router to see if the sync stays up - clarifying if it is internal or external noise.

If I got BT out would they just fob me off??

Edited by wolvesmad (Wed 04-Aug-10 11:00:10)

up until around 10-10:30 and then for no apparent reason just drops

about when it gets dark ?

Goes dark around 9:45 - jitter kicks in on the connection at around 9:15.

there will be more AM radio interference as the sun goes down, then there's the street lights and stuff in peoples homes firing up. We always use interleaving on long lines, it's designed to handle errors.

The UPS may put out more noise than enough - if you router is 12V run it on a car battery

Is there anyway I can minimise the impact on latency regarding interleaving??

Disable DLM the only people that benefits are the provider, turn it off, set the snr at certain acceptable level then leave it

That's very difficult to do on BT lines. DLM is more of a compulsory setting.

Matt

Nope

Turn it on and will give higher latency but better stability for your line. Keep it off, better latency but worse stability - some lines are just like that.

Is the lower latency really mission critical?

Matt

Disable DLM the only people that benefits are the provider

yeah, right. Stability is of no interest to anyone. Far better to have a bigger number on a router stats page than a more reliable and perhaps even faster in practice service.

it's a 10 ms penalty, compared to the problems you now have.

MaxDSL has a single setting which is quite a deep level of interleaving.

I beleive WBC was going to offer more options in the depth of interleaving which I assume would reduce the ping penalty.