Kitz Forum
Broadband Related => Broadband Technology => Topic started by: kezzaman on June 15, 2012, 07:09:46 PM
-
Do any of you geniuses know how to increase upstream snr on the netgear dg834gt? :-\
-
Do any of you geniuses know how to increase upstream snr on the netgear dg834gt? :-
Can't be done as the exchange basically controls the SNRM in the same way the router that the router can (by tweaking it), thus it cannot be changed.
Somebody correct me if I'm wrong :).
-
Should ISPs be able to increase upstream snr?
-
Should ISPs be able to increase upstream snr?
No, all they can do is uncap your upstream on 21CN decreasing the upstream SNRM as a result, giving you upstream speeds of about 1Mb/s (on LLU, the upstream is uncapped by default I believe.) Or they can switch you to Annex M (decreasing the upstream SNRM as a result), giving you upstream speeds of up to 2.5Mb/s (you need ADSL2+).
What do you currently get? Is there any reason why you want to change the upstream SNRM?
-
Should ISPs be able to increase upstream snr?
No, all they can do is uncap your upstream on 21CN decreasing the upstream SNRM as a result, giving you upstream speeds of about 1Mb/s (on LLU, the upstream is uncapped by default I believe.) Or they can switch you to Annex M (decreasing the upstream SNRM as a result), giving you upstream speeds of up to 2.5Mb/s (you need ADSL2+).
What do you currently get? Is there any reason why you want to change the upstream SNRM?
I actually want to increase the snrm on my upstream because its unstable.
-
I actually want to increase the snrm on my upstream because its unstable.
The simple answer is no, sorry :(.
-
I actually want to increase the snrm on my upstream because its unstable.
The simple answer is no, sorry :(.
Really not even my isp can do it? :o
-
I actually want to increase the snrm on my upstream because its unstable.
The simple answer is no, sorry :(.
Really not even my isp can do it? :o
No :(.
-
So if i lived twice as far from the exchange would my upstream snrm be exactly the same as it is now?
-
So if i lived twice as far from the exchange would my upstream snrm be exactly the same as it is now?
Not exactly. There are three factors which affect the upstream speed (talking about 21CN/ADSL2+ here):
- the upstream target noise margin (6 dB on BT systems) means that in most cases that will be the noise margin at the time the connection is established.
- the number of tones allocated to the upstream part of the connection puts a maximum limit on the upstream speed. On a short line, this maximum limit may be reached without bumping into the target noise margin, so in this case the noise margin will be higher than the target.
- the amount of interference will affect the speed achieved for the given target noise margin.
So in most cases, the noise margin at connection time will equal the target noise margin, but on short lines it may be higher. After the connection is established, the noise margin will change, depending on interference conditions.
-
So if i lived twice as far from the exchange would my upstream snrm be exactly the same as it is now?
Not exactly. There are three factors which affect the upstream speed (talking about 21CN/ADSL2+ here):
- the upstream target noise margin (6 dB on BT systems) means that in most cases that will be the noise margin at the time the connection is established.
- the number of tones allocated to the upstream part of the connection puts a maximum limit on the upstream speed. On a short line, this maximum limit may be reached without bumping into the target noise margin, so in this case the noise margin will be higher than the target.
- the amount of interference will affect the speed achieved for the given target noise margin.
So in most cases, the noise margin at connection time will equal the target noise margin, but on short lines it may be higher. After the connection is established, the noise margin will change, depending on interference conditions.
Ok but do you know how it changes and why it cant be done manually? :-\
-
I think you may be getting SNR Margin mixed up with Target SNR(M)... and also real SNR.
Target SNRM basically stays the same..... but the downstream Target SNRM can be changed to give a larger margin to allow for fluctuations in REAL SNR. The, fluctuations that we see from our router is the SNR Margin (as an average over all the frequencies).
The difference between real SNR and the SNRM is what decides how many bits are looaded at that particular frequency.. which is what decides what speed you are going to get.
Perhaps better reading the pages on the main site which explains it all in greater detail
What is SNR etc
http://www.kitz.co.uk/adsl/linestats.htm#SNR
-
Ok this is quite confusing. Basically ive noticed that i dont have any issues when my SNRM is 13.3 dB or more but most of the time its lower than this usually between 11 and 13dB. Sometimes when i play around with setting on my router my snrm jumps to around 13.5dB, also whenever talktalk switch my profile the snrm jumps to 13.5dB (regardless of what they switch it to) but after a couple of days it drops back down and i experience really bad lag when gaming.