More broadband issues..

[The Natural Philosopher]

Last posted to feb 2007. I will get a LONG way with that BBS I am sure.

[The Natural Philosopher]

Has to be about the most useless site I have tried today.

No tech info, and the speed test didn't work because it didn't expect what I have here.

[Pete C]

On Nov 11, 10:02 pm, The Natural Philosopher wrote: .> At various times the connection goes gritty, and the log files show its

I'd try a laptop and USB speedtouch modem straight into the master socket.

cheers, Pete.

[The Natural Philosopher]

Ok, give me one and I will.

[Andy Hall]

As it were.

yes it connects you to customer retention. It's surprising what gifts are then showered be it ISPs, mobile operators or others

Leopard?

[Pete C]

On Nov 12, 7:55 pm, The Natural Philosopher wrote: .> > I'd try a laptop and USB speedtouch modem straight into the master

You can get a speedtouch modem off Ebay for about a fiver.

cheers, Pete.

[Andy Hall]

USB?

That just compounds an already bad situation. A better solution is to buy something like a Cisco 800 or 1800 series.

[The Natural Philosopher]

and the laptop?

More than a fiver I am sure.

[The Natural Philosopher]

I lost mine....

[The Natural Philosopher]

I would, if I felt it would help..

[Pete C]

If only one PC just try a USB modem instead of the router.

cheers, Pete.

[The Natural Philosopher]

Two macs and a Linux.

well there is a PC about 40 meters from the access point..built in somewhat.

So you see, it still not HELPFUL.

[Pete C]

On Nov 12, 9:38 pm, The Natural Philosopher

Weeeell,

Try the USB modem with the mac or linux box?

cheers, Pete.

[Pete C]

On Nov 12, 8:53 pm, Andy Hall wrote: .> That just compounds an already bad situation.

And appoint a Cisco certified specialist to come and install it :)

[Duncan Wood]

At which point you could just buy your own cable shark.

[tony sayer]

Hardly think thats necessary. Seems to me that the line isn't all it ought be.

Also some routers, and I haven't had any experience of the one in question, sometimes benefit on a change of firmware..

Be also interesting in NP's case to see if any of his neighbours are having the same or similar problems in case theres something odd going on at the exchange some out in the sticks have very limited backhaul .

Perhaps he ought move near that town he despises so much then he could have VM;)....

[The Natural Philosopher]

I am, or was..a cisco certified specialist.. ;-)

[Alex Selby]

The Natural Philosopher wrote: ...

Hi NP. Just to let you know, I had similar symptoms to you earlier this year. I also thought for some time that it was the line that was at fault.

In fact the fault cunningly mimicked the symptoms of a line fault and several other obvious possible problems (e.g., computer noise on the ordinary phone line - sounds like it has to be a filter problem. A dozen filters later... Hmm perhaps the filter isn't the problem.)

To cut a very long story short, it turned out (eight months of hold music later - I feel really stupid for being so patient with the useless ISP) that the problem was with their equipment at the exchange. Not all their equipment - just (as far as I can make out) the line I happened to be plugged in to. Maybe 1 connection in to a card which can support 32 people. When they moved it to a different connection (a "lift and shift"), suddenly everything worked nicely...

...until another problem cropped up, which cutting another story short turned out to be caused by a nearby faulty street light.

Anyway, just saying that what looks like a clear line fault may be something else. Who is your ISP? What is your exchange? (Hunt around

to find out.) Do the problems occur regularly at certain times of day, or at random? Is your modem/router rated to cope with whatever new-fangled brand of ADSL that they are using?

[Dave Liquorice]

Agreed, my line is about 11k feet (3.5km) and the downstream attenuation is 43dB. As previously stated my SNR for a stable connection somewhere between 5,000 and 5,500kbps is about 13dB+ during the day dropping to mid/low single figures at night. Upstream the attenuation is 22dB and SNR

21dB (current SNT figure, I don't watch the upstream side that always works flat out).

Not getting above 3.5 or 4dB SNR indicates something a miss. Is the line used for voice calls at all? Putting a proper clanging bell (or 4) on the end of the line and blasting a bit of ringing current through might clean up a slightly iffy connection.

As for notches in the symbols/frequency graph there is a reserved frequency at (IIRC) 277kHz and you may see ones associated with broadcast stations. Radio 4 on 198kHz shows here and at the top end (>630kHz) notches from local MF transmitters, stations such as Radio 5 Live (693,

909Khz) and Talk Sport (1053, 1089Khz) as well as local radio MF transmissions.

I take it you have read all the guides that are about describing how to squeeze the last kbps out of a ADSL connection. Have just one high quality filter at the earlist point possible on the incoming line, feed all your POTS stuff from that single filter. Place the modem at the filter and run CAT5 from it to your router/switch/PC/WHY.

[The Natural Philosopher]

Mmm. Ive been digging away at the web and more stuff is slowly floating to the surface like turds in a cesspit.

Its pretty clear that what is happening is that I am running for some reason on a very low SNR (3-4dB) at rather too high a rate for the line.

BT tests for my postcode estimate 2.9Mbps.

Clara net say my line is currently set to 4500 maximum stable rate (3600 or so fault threshold) which I agree is probably about right. BUT the connection keeps resyncing at > 5Mbps.

I thought the 'learning' process should have got the DSLAM to limit me to around 4Mbps

So all in all I am fairly clear that what is happening is that the DSLAM and my router are simply trying too hard and leaving no margin for e.g. the car with the cracked distributor going past etc. ;-)

Now what I need to do is somehow get the DLSAM or my router to settle on something less ambitious with maybe a 4Mps connection..its not a great deal of use going past that as the contention ratio limits me to 3.8 Mbps anyway.

I don't seem to be able to reste the acceptable noise margin in the router..been trying to find ways of fooling the remote kit.

One thing I have discovered, and that is judging by whats been posted BT's support is even worse 'Chupatti chewing cow factory in bangalore' and the technique of blaming the customers own kit is well established.

It all boils down to teething problems with new technology:(BT MAX) The DSLAMS are supposed to set a rate for the line over a 10 day period - which has expired for me now, and that should be set such that an acceptable error rate is achieved, with low probability of disconnection. If multiple disconnects occur, the rate is lowered, and eventually a rate is set,and if you go below that BT acknowledges a line fault. My rate is simply set too high..whether tats something the DSLAM decides or the router decidess or both, is still unclear.

One thing did glean, and that is that taking the connection down and leaving it off for a minute, causes the DSLAM to re-think itself. Also multiple disconnects, so if you simply retrain a lot manually, maybe it will decide that something is up and lower its threshold.

If anyone know more, I am willing to learn..