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My signal noise ratio often drops very low to around 4-5 db in the evenings often resulting in loss of connection, but is around 9 during the day.
Am I right in thinking I can ask to have my noise ratio raised, but it can result in slower speeds?
How much of a speed loss does it cause?
My current router stats:
Line Attenuation (Up/Down) [dB]: 22.5 / 42.0
SN Margin (Up/Down) [dB]: 22.0 / 6.0
The target SNR margin can be set to 6, 9, 12 or 15 dB - but BT usually won't do this unless there is an actual fault reported with them first. The other option is Interleaving, which can reduce errors on your line and help stop the drop-outs in the first place. The higher the SNR is set, the lower the connection speed will be.
James
You could ask BT, via Enta, to have the target margin raised but I think that would be a drastic step to take.
If the router is dropping the connection at a SNR of 4 or 5 then I suggest you consider getting a better router. My ST585v6 was able to hold synch as low as 2.5 when BT were screwing with my line recently.
The smarter option, meanwhile, would be to reboot the router when the margin is at its lowest, in the evening. That way you shouldn't have disconnects. But consider getting a better router.
Ircsum.
So is interleaving a good option?
I had a Netgear router and when the line dropped would not automatically reconnect. I changed to a Speedtouch 585 which does auto reconnect quickly, but the line still drops occasionally. Only in the evenings so presume it is the SNR.
tboorman
18/03/2007, 19:01
If you use VoIP or are into online gaming, you wouldn't really want interleaving turned on.
If you use VoIP or are into online gaming, you wouldn't really want interleaving turned on.
Oh I occasianally do online gaming. :(
Think i'll just put up with it. With this router it more stable then it was and it's not so often.
First thing I'd recommend is to ensure your sockets/wiring is all correct - www.dslzoneuk.net/socket.php - it's helped so many peopl over the past few years...
First thing I'd recommend is to ensure your sockets/wiring is all correct - www.dslzoneuk.net/socket.php - it's helped so many peopl over the past few years...
I put a new master socket filter on and just had the internal wiring replaced by BT.
Just because BT have re-wired everything does not mean they have done it correctly (and with ADSL in mind). Can you check the sockets to see what wires are hooked up in each?
Thanks
James
Thanks for all the info. I fitted one of these... http://www.adslnation.com/products/xte2005.php so presume it's wired correctly as it's different inside to the normal BT socket therefore cannot see how the wires are connected.
If you take that faceplate off, just check to see what wires are connected to the back of the XTE2005...
If you take that faceplate off, just check to see what wires are connected to the back of the XTE2005...
None! Theres a plug that goes into the test socket. I'll take a pic soon.
Thats good then - not much else you can do!
Thers a diagram of it here... http://www.adslnation.com/products/xtespec.php and i haven't any extensions.
shone1977
24/03/2007, 21:27
can some one tell me if these are good or bad
ADSL Link Downstream Upstream
Connection Speed 7616 kbps 832 kbps
Line Attenuation 23 db 6 db
Noise Margin 11 db 8 db
Excellent shone.
.......but don't tell Staticshock :rolleyes:
Upstream attenuation is a bit low, but if no probs then don't worry, it could be a router bug
Office package eh?
staticshock
24/03/2007, 21:33
Excellent shone
.......but don't tell Staticshock :rolleyes:
Office package eh?
HA HA LMAO:mad:
surfer_chick
24/03/2007, 21:44
You've also got interleaving switched ON shone. With stats like that you'd be ok to have it taken off and your speed/profile will raise slightly :)
staticshock
24/03/2007, 21:55
You've also got interleaving switched ON shone. With stats like that you'd be ok to have it taken off and your speed/profile will raise slightly :)
how do you know that
tboorman
24/03/2007, 22:03
The maximum sync speed of a line which has interleaving on is 7616 kbps.
shone1977
24/03/2007, 22:34
Is ther anything i can do to to help my Upstream attenuation or is it a BT thing!
The maximum sync speed of a line which has interleaving on is 7616 kbps.
Tim
I have an interleaved connection rate of 8096 down and 448 up
That's the exception to the rule, Robbie - I think it means there's no Forward Error Correction but I'm not 100% sure of that. I've seen isolated cases of that synch with interleaving before.
Ircsum.
Cheers Ircsum
Yes, I have seen it before occasionally. Anyway, I have requested interleave be turned off. Might not see much improvement in d/loads, but could improve my 100+ms ping rate :)
shone1977: The upstream attenuation is nothing to worry about. It's just an indirect measure of the loop length and it's possible your router is misreporting it. You don't need to do anything. :)
Ircsum.
Robbie: As a matter of interest, are your router stats showing any FECs?
Ircsum.
Robbie - you should not be getting pings of over 100ms even on Interleaving. Can you drop us a ticket/email with some ping results etc.
The 8096 Interleaving issue is something of a mystery. This usually happens when a line is ok at the full 8128 on Fast mode, and the for some reason Interleaving gets turned on but only drops the connection to 8096 instead of 7616. As Ircsum says, it's not usual practise.
Thanks
James
Robbie: As a matter of interest, are your router stats showing any FECs?
Ircsum.
Hi Ircsum
At the moment I have my Belkin 7633 plugged in and error stats are not available. I'll plug the ST585 in later and have a look.
James
Here are a couple of screenshots taken today
Router stats --> http://i14.photobucket.com/albums/a328/robona5/ScreenShot026.jpg (http://www.adsl24.co.uk/forum/redirector.php?url=%68%74%74%70%3a%2f%2f%69%31%34% 2e%70%68%6f%74%6f%62%75%63%6b%65%74%2e%63%6f%6d%2f %61%6c%62%75%6d%73%2f%61%33%32%38%2f%72%6f%62%6f%6 e%61%35%2f%53%63%72%65%65%6e%53%68%6f%74%30%32%36% 2e%6a%70%67)
Ping result --> http://i14.photobucket.com/albums/a328/robona5/ScreenShot025.jpg (http://www.adsl24.co.uk/forum/redirector.php?url=%68%74%74%70%3a%2f%2f%69%31%34% 2e%70%68%6f%74%6f%62%75%63%6b%65%74%2e%63%6f%6d%2f %61%6c%62%75%6d%73%2f%61%33%32%38%2f%72%6f%62%6f%6 e%61%35%2f%53%63%72%65%65%6e%53%68%6f%74%30%32%35% 2e%6a%70%67)
I put in a request yesterday for interleave to be turned off
*EDIT* pinging www.adsl24.co.uk (http://www.adsl24.co.uk) gives results of around 37 - 39ms
Defininitenly something wrong there - whats your MTU set at and does it happen on both your routers. Also, tried another PC if possible?
Interleaving request was submitted to BT yesterday so it should be off within 48hrs now.
James
Hi James
MTU is set at 1492, no packet loss at all. Not tried the Speedtouch since I've been on MAX, so its been a few months.
Profile is 7000 and throughput is usually around 5500 -6500kbps early morning.
The wifes PC shares the same connection, we are both wired to the router, and her pings and MTU are the same as mine.
Let us know what pings are like with the Speedtouch.
James
shone1977
28/03/2007, 12:56
Hi just tried another router is this better the old router was a netgear dg834 the new one is a 3com3crwdr200a-75
Downstream Upstream
SNR Margin (dB): 14.0 9.0
Attenuation (dB): 21.0 12.0
Output Power (dBm): 19.7 11.9
Attainable Rate (Kbps): 10624 1052
Rate (Kbps): 7616 832
K (number of bytes in DMT frame): 239 27
R (number of check bytes in RS code word): 16 16
S (RS code word size in DMT frame): 1 8
D (interleaver depth): 16 2
And is it realy worth getting interleaving taken off what real benefit it there and is there a downside?
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