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Standard User yuvi86
(newbie) Fri 21-Mar-14 15:06:44
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DSL SNR (DownstreamLow) and SNR(UpstreamHigh)


[link to this post]
 
These are the stats of my modem
DSL Status Connected
Downstream Data Rate 3890 kbps
Upstream Data Rate 494 kbps
DNS Primary 218.248.245.1
DNS Secondary 218.248.255.141
Max Att Downstream Rate 4648 kbps
Max Att Upstream Rate 1117 kbps
SNR (Downstream) 7.0 dB
SNR (Upstream) 24.0 dB

Line Attentuation(Downstream) 37.0 dB
Line Attentuation(Upstream) 19.0 dB
Gateway IP 0.0.0.0
My snr down stream is low while my snr upstream is high.A day ago with this snr downstream ratio i had frequnt disconnects,but after contacting ISP even at this low SNR my connection is stable.
I have read a lot about snr.The minimum SNR margin is arround 10dB ,But suprisngly my connection is stable.

Before contacting ISP the stats where as follows
DSL Status Connected
Downstream Data Rate 3890 kbps
Upstream Data Rate 494 kbps
DNS Primary 218.248.245.1
DNS Secondary 218.248.255.141
Max Att Downstream Rate 4648 kbps
Max Att Upstream Rate 1117 kbps
SNR (Downstream) 7.0 dB
SNR (Upstream) 6.0 dB

Line Attentuation(Downstream) 37.0 dB
Line Attentuation(Upstream) 19.0 dB
Gateway IP 0.0.0.0

Can anyone help me out why is it so.
Standard User RobertoS
(sensei) Fri 21-Mar-14 23:08:25
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Re: DSL SNR (DownstreamLow) and SNR(UpstreamHigh)


[re: yuvi86] [link to this post]
 
Hi. Welcome to the forums smile.

(To anyone else looking at the issue, having typed all that follows I have checked the DNS servers. They belong to Bharat Sanchar Nigam of New Delhi, so I suspect the OP is in India and UK norms do not apply. Hence my strikeouts).

You do have some strange stats there, but let's cover a general point first.

On most lines on most ISPs, the downstream SNRM should vary over 24 hours by 2-3dB or less above or below 6dB, depending on the time of day that you connected. I don't know where your 10dB figure comes from, but it is incorrect.

On a few ISPs the 6dB figure I stated may be 9dB.

It would help us if you tell us the ISP, as we now most of the different settings they apply.

Is there a reason you are looking at these stats? In particular, have you had recent problems? The reason I ask is that the 3890kbps downstream data rate for a 37dB attentuation is dreadful.

Edit - tripe removed, thanks to XRaySpeX.

My broadband basic info/help site - www.robertos.me.uk | Domains,site and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 59.4/14.4Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
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Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.

Edited by RobertoS (Fri 21-Mar-14 23:54:44)

Standard User XRaySpeX
(eat-sleep-adslguide) Fri 21-Mar-14 23:49:01
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Re: DSL SNR (DownstreamLow) and SNR(UpstreamHigh)


[re: RobertoS] [link to this post]
 
In reply to a post by RobertoS:
Secondly, the upstream SNRM is normally within a few dB of double the downstream.
Eh? You confusing with Attenuation and 'half'?
Operation Data Upstream Downstream
Noise Margin 5.9 dB 5.8 dB
Line Attenuation 13.0 dB 25.5 dB


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Standard User RobertoS
(sensei) Fri 21-Mar-14 23:54:11
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Re: DSL SNR (DownstreamLow) and SNR(UpstreamHigh)


[re: XRaySpeX] [link to this post]
 
[gulp]
Yes indeed.

See the edited version smile.

My broadband basic info/help site - www.robertos.me.uk | Domains,site and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 59.4/14.4Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
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