Thread: SNR query

HI

We know that higher the SNR and lower the attenuation the better the speed we get. Now here is a tricky question. When we go for an unlimited connection the speed we get is 256 kbps and for other plans we get 2 mbps. Now when BSNL regulates the speed does they do it by regulating this SNR and attenuation parameters or they limit the bandwidth by other means. I mean if I am able to change my SNR in Home 750 where I get a speed of 256 kbps to a higher SNR value will I get better speeds. I hope SNR is controlled in local exchange and not at DATA NETWORKS Bangalore.

NO. BSNL will connect you to the server applicable to your speed.
Depending on MOD mode selected ( usually GDMT for low speeds)
The SNR, line speed actual will vary, within selected tariff plan.
In Airtel, we have an option to increase "Speed On demand"
for fixed hours and have to pay extra.

I dont think they use SNR to regulate bandwidth ..... They must be using other means ....
There is a lot of bandwidth overhead involved if speeds r decreased using SNR .....

I cant get you. Sometimes I get connected as GDMT and sometimes I get connected as ADSL2+. Please help me

Give me the actual technicalities involved in speed regulation

Give me the actual techincalities involved in speed regulation.

SNR and Attenuation are not controlled by any setting, they are measures of quality of signal being received on your wire.

SNR stands for Signal to Noise Ratio and is basically the difference between the level of the signal being received compared with the natural noise level on the line.

So higher SNR number means you are receiving a stronger signal.

Attenuation measures how much signal strength is being lost between BSNL and your end.

For 2 Mbps attenuation less than 45 dB is good.

Tutorials - ADSL > Understanding Line Loss and Measurements

Bad line quality may effect your max speeds. If so check if you are using a splitter also you could get your line checked by your local BSNL exchange.

Thanks for the clarification cable guy .... I too got confused by his doubt ....

Using Noise to regulate bandwidth ??

What i meant by my previous post is that if they increased the noise in the signal ...it may decrease the bandwidth u can use ....but will not change the amount of bandwidth they have to provide u ....

Lots of Bandwidth gets wasted transmitting noise = Overhead incurred

SNR and Attenuation are not controlled by any setting

Beetel 110BX1 Dataone 59.xx.xx.xx upto 2 Mbps inspiron 8000
7:43 AM 10/30/2008
Mode: G.DMT
Type: Interleave
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 32.9 25.0
Attenuation (dB): 17.0 3.0
Output Power (dBm): 12.3 15.1
Attainable Rate (Kbps): 9024 1024
Rate (Kbps): 2048 512
7:53 AM 10/30/2008

Mode: T1.413
Type: Interleave
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 32.3 13.0
Attenuation (dB): 16.0 3.5
Output Power (dBm): 12.3 7.7
Attainable Rate (Kbps): 7968 608
Rate (Kbps): 2048 512

7:59 AM 10/30/2008

Mode: ADSL2+
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 35.1 21.7
Attenuation (dB): 19.0 6.8
Output Power (dBm): 10.4 20.1
Attainable Rate (Kbps): 15576 44460
Rate (Kbps): 2047 510

Originally Posted by essbebe

Beetel 110BX1 Dataone 59.xx.xx.xx upto 2 Mbps inspiron 8000
7:43 AM 10/30/2008

Yes, of course when your adsl modem uses different connection methods, the signals will be different therefore the SNR (signal-to-noise ratio) will also be different.

What I meant is that SNR is not some number which you can set in your modem settings.

out of thread.
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Originally Posted by essbebe

out of thread.
a useful utility Winutilities free today. with key.

Giveaway of the Day - free licensed software daily - Spread the Word

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