Unsolvable Internet Problem!

Hairboi

Hairboi

Hairboi

Associate
Joined
2 Oct 2006
Posts
538
For the past 12 weeks, my internet has been very unstable. I decided to find out why, and rang my ISP (ADSL24), and they detected an error on the line, and advised me to contact BT. I did so, they asked me to plug a phone into the test socket and listen for a dial tone, there was none. The technician said that the problem is in the phone line, and sent out an engineer to fix it. He put in a new wire that goes from the street to my house, and now i get a dial tone. I figured this would fix it, and he went home at around 5pm yesterday evening, he's sending round another engineer to tidy up the wiring in the next 24 hours, so essentially, the new wiring is done. However I'm still getting disconnects on my line. So i tried yet another new router, new microfilter etc, and it's still unstable. Sometimes, every few minutes the router loses sync with the exchange, then reconnects, sometimes it will last a few hours.

Downstream Rate: 284 Kbps
Upstream Rate: 445 Kbps
Downstream Margin: 31 db
Upstream Margin: 23 db
Downstream Line Attenuation: 24
Upstream Line Attenuation: 13

Those are my router stats at the moment.

I have actually exhausted all options, it's definitely a problem between the BT faceplate and the exchange, but i can't figure out what. Could ADSL2+ be contributing to the problem, which I upgraded to for no extra cost a while back. Back when i was on normal ADSL, it was stable for over a year, i didn't notice even one disconnect.
 
ADSL24 were feeding you a line. You should never be told to contact BT about an ADSL fault unless BT Retail are your ISP - if nothing else, there's no one at BT you can speak to who can do anything about it.

It sounds like you've got a voice fault as well though.
 
Those line stats are pretty good, great actually.

Definitely something odd going on. Sure there is nothing else in your property on the same line that's not filtered or has chewed up cabling etc?
 
Indeed.

Whilst you should contact BT about the voice fault, only your ISP should be contacting BT about an ADSL fault.

However, I'd be tempted to wait until BT clear the voice fault as this may clear the ADSL instablilty....and I'd get the ISP to reset the SNR margin as 31dB margin is about 25dB to high, and you should be getting MUCH faster sync speeds but the margin is limiting it dramatically.
 
PistolPete said:
and I'd get the ISP to reset the SNR margin as 31dB margin is about 25dB to high, and you should be getting MUCH faster sync speeds but the margin is limiting it dramatically.
Click to expand...

..........................:confused:

What?

You want a big of a SNR as you can and as little Attenuation as possible. 6dB of SNR would be 'ok' but certainly not desirable..
 
Last edited:
You don't want it as high as possible at the expense of speed, and certainly not as high as 31dB. 6dB of SNR would be perfectly fine, and the OP would probably be connected at a stable 8Mbps to boot...
 
tolien said:
ADSL24 were feeding you a line. You should never be told to contact BT about an ADSL fault unless BT Retail are your ISP - if nothing else, there's no one at BT you can speak to who can do anything about it.

It sounds like you've got a voice fault as well though.
Click to expand...

ADSL24 looked into the line and came back saying it's a copper line failure and that it's a fault on BT's end (who i rent the line off). They came, found the fault (wasn't getting a dial tone with a phone plugged in), they went home earlier today, however i'm still getting disconnects (had about 30 today)
 
PistolPete said:
Indeed.

Whilst you should contact BT about the voice fault, only your ISP should be contacting BT about an ADSL fault.

However, I'd be tempted to wait until BT clear the voice fault as this may clear the ADSL instablilty....and I'd get the ISP to reset the SNR margin as 31dB margin is about 25dB to high, and you should be getting MUCH faster sync speeds but the margin is limiting it dramatically.
Click to expand...

They won't reset the SNR until they know the line is stable.
 
Hairboi said:
ADSL24 looked into the line and came back saying it's a copper line failure and that it's a fault on BT's end (who i rent the line off). They came, found the fault (wasn't getting a dial tone with a phone plugged in), they went home earlier today, however i'm still getting disconnects (had about 30 today)
Click to expand...

Unless you had a voice fault, ADSL24 should still have been doing the running.
 
Highest managed SNR target margin is usually 15db - its so high because his sync rate is so low.

Have you made sure the line is filtered correctly internally and that the ring wire is disconnected? also while you shouldn't have to if the main socket is filtered before any extensions I've found in some cases adding a filter before any telephones at the end of long extensions can help - not sure why.
 
Rroff said:
Highest managed SNR target margin is usually 15db - its so high because his sync rate is so low.

Have you made sure the line is filtered correctly internally and that the ring wire is disconnected? also while you shouldn't have to if the main socket is filtered before any extensions I've found in some cases adding a filter before any telephones at the end of long extensions can help - not sure why.
Click to expand...

Yep, it's all filtered correctly, the BT engineer checked it all. I have a feeling it's that my line dislikes ADSL2+.
 
Hairboi said:
Yep, it's all filtered correctly, the BT engineer checked it all. I have a feeling it's that my line dislikes ADSL2+.
Click to expand...

Not likely, it's broadly the same technology at the end of the day, only thing which could take an issue to ADSL2+ would be a faulty DSLAM line card or a faulty router really (so basically not the line)
 
If you get a chance try a Netgear DG834GT router on the line - I was previously dropping sync to as low as 2.5mbit and tripping interleaving several times - change to this router (unfortunatly it hard locks a couple of times a month) but it clings on like a limpet and despite a few thousand CRC errors every day its holding sync at 7.2Mbit fastpath.
 
Hairboi said:
They detected an error with the actual phone line, surely that means only BT can come and fix it?
Click to expand...

A different part of BT than you can talk to though. Like I said, if there was only an ADSL fault, ADSL24 should have been chasing it for you through BT Wholesale.
 
To over simplify the SNR is a measure of how "clearly" the data is coming through - as ADSL is based on radio frequencies theres always some interference. If its not having to send much data through (low sync) then it can send the info very clearly and you get a high SNR read out - as you send more data through it becomes more difficult to distinguish the individual parts of the data from the background noise and the SNR readout drops...

BT set the 6db target as how far the system lets it drop before it stops trying to send more complex signals through as a safe value to ensure clarity of the data coming through. The more complex the signal it can send the faster you can transmit information - higher sync.
 
Last edited:
I have tried 3 different routers, 2xDG834GT and a Linksys one which i installed yesterday. The BT engineer assured me the line is completely fine, and i've done everything possible on my end, tried different routers, microfilters, ethernet cables, in test socket, in the faceplate. No matter what it still d/cs. We have another line in this house which works perfectly, it's right next to my line and never d/c's, but its on a different ISP.
 
You must log in or register to reply here.
Back
Top Bottom