Line Speed and Noise

[swsup97]

Can anyone tell me if my Line attenuation and noise margin is acceptable , don't have anyone else to make a comparison to see what is the norm - since i was upgraded to a 4MB line earlier this year i have never seen the line speed go above 2.6mb


ADSL Link Downstream Upstream
Connection Speed 2599 kbps 511 kbps
Line Attenuation 43.5 db 23.5 db
Noise Margin 10.9 db 12.1 db

 

[Pada]

Here's a good reference post where you can compare your line quality: http://mybroadband.co.za/vb/showpost.php?p=1239914&postcount=7

 

[ichigo]

your noise margins are quite bad for your speed you should drop to 2 meg line for stability
Your Line attenuation is fine for 4 meg theres definitely something wrong with your line causing your low DB and sync speed.
You should report your line to telkom.

Heres my stats to compare:
DSP Firmware Version E.25.41.55 A
Connected true
Operational Mode G.Dmt
Annex Type AnnexA
Upstream 512000
Downstream 4096000
SNR Margin(Upstream) 28 dB
SNR Margin(Downstream) 22.5 dB
Line Attenuation(Upstream) 5.0 dB
Line Attenuation(Downstream) 7.0 dB
CRC Errors(Upstream) 964
CRC Errors(Downstream) 0
Latency(Upstream) Fast
Latency(Downstream) Fast

 

[Pada]

Merenwenrago: very few people are as lucky as you are to have such low Line Attenuation values and as high SNR margins.

swsup97: This is probably a better post (than my previous link) with regards to the SNR and Line Attenuation values http://mybroadband.co.za/vb/showthread.php/186156-Understanding-SNR-and-Attenuation-Rates
I'm not sure why your line is giving you problems with those line statistics, unless they vary a lot. I've seen stable 4Mbps lines with Line Attenuation values of 50dB, but that was probably with a decent DSLAM and proper router too.
The difference between a Line Attenuation of 50dB and 43dB is actually quite significant (43db = 10 ^ 7 lower loss on the signal than 50dB line attenuation).

A line attenuation of 43dB for a 4Mbps line is OK and should be more than enough for it to be stable, however your SNR margin is reasonably low. You want it to be 12dB or higher at all times.

 

[swsup97]

Thanks guys for the feedback

I logged a call with Telkom to check for noise/errors on my line - all i got back was an sms saying call is closed and problem fixed yet nothing has changed from my side, i can't really complain - read a few horror stories on here with other people having experienced worse.

Will wait and see when these speed upgrades take place if any different then.

 

[Pada]

Reset your router and see if it syncs at 4096kbps down/512kbps up again. If it doesn't, then you can always ask Telkom to switch you down to 3Mbps or perhaps 2Mbps, which should definitely get your line stable again.

My office is running the 4Mbps ADSL line at 2Mbps, since the signal quality is just too poor to run stable at 4Mbps. For us, having a stable connection is more important than the speed.