No Guarantee on 384K line speed - due to distance from exchange ?

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Kompete

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I recently moved house and had to re-apply for my 384K line. I have an unshaped account with Webafrica.

Since I started using the line I have never been able to get more than 210K line speed. At my previous place I always got a stable +/- 320K line speed (with my unshaped account)

I complained to Telscum, who said that they offer up to 384K line speed; and that the actual speed is dependant on the distance from the exchange (there appears to be no fault on the line). In my case the distance seems to be 5km.

This is BS.:( I specifically got the unshaped account so I am at least certain of a 300K speed, but now I am getting sub 210K.

Is there any other way to resolve this. I already escalated this to the esc centre.

Tx
 
There are so many other factors besides the line length that influence speed and sync rate. Keep complaining. Also, check around your house for anything that might interfere with the DSL signal (bulbs, CFLs, transformers, corrosion, bad wiring etc.)
 
Kompete said:
This is BS.:( I specifically got the unshaped account so I am at least certain of a 300K speed, but now I am getting sub 210K.
Tx
Click to expand...

The fact that you have an unshaped account has absolutely nothing to do with your line speed.
 
What does your line actually sync at? Look at your router info page.
Dont go by speedtests for this
 
deweyzeph said:
The fact that you have an unshaped account has absolutely nothing to do with your line speed.
Click to expand...

I thought having unshaped ensures that I will always have the max line speed possible?
 
Kompete said:
Again, how exactly do I determine my line stats? thx
Click to expand...
Go to your router login page. To do this, in the address bar in IE or Firefox type (in my case) 10.0.0.2. Enter your username and password, which by default could be admin and admin. And on that front page it should say what speed you are synced at. It should be something like 384/128
 
Yeah, sorry, what Just_Ice said.

Depending what router you have, go to its web interface.

On Telkom routers it's usually http://10.0.0.2

On some others, it's http://192.168.2.1

Once you have logged in, you will be able to look around for noise margin and/or attenuation stats usually given as a decibel value.
 
Line Stats

Pulled the following info from my router web interface (modem status):

Modem Status
Connection Status Connected
Us Rate (Kbps) 128
Ds Rate (Kbps) 256
US Margin 12
DS Margin 13
Trained Modulation ADSL_G.dmt
LOS Errors 0
DS Line Attenuation 57
US Line Attenuation 31
Peak Cell Rate 301 cells per sec
CRC Rx Fast 1424
CRC Tx Fast 77
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path

DSL Statistics
Near End F4 Loop Back Count 0
Near End F5 Loop Back Count 0
 
Kompete said:
Pulled the following info from my router web interface (modem status):

US Margin 12
DS Margin 13

DS Line Attenuation 57
US Line Attenuation 31
Click to expand...

Bottom line is you have a k@k line, sorry.
 
Spooner said:
What should it be around out of curiousity for a 384K line?
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Well that's relative depending on the quality of the line quality.
My own 384k line, SNR: 40 dB, Attenuation: 22 dB


Jacklondon said:
Hi

There are many things you can take into consideration, but I usually only care for these.

Attenuation Rates:

20bB. and below = Outstanding
20dB-30dB. = Excellent
30dB-40dB. = Very Good
40dB-50dB. = Good
50dB-60dB. = Poor and may experience connectivity issues
60dB. and above = Bad and will experience connectivity issues



For S/N Margin Readings:

6bB. or below = Bad and will experience no line synchronisation or intermittent synchronisation problems.
7dB-10dB. = Fair but does not leave much room for variances in conditions.
11dB-20dB. = Good with little or no synchronisation problems
20dB-28dB. = Excellent
29dB. or above = Outstanding

If these are good, then start experimenting with the others.
Click to expand...
 
Last edited:
What would you say about my line ???

Connection Status Connected
Us Rate (Kbps) 512
Ds Rate (Kbps) 4096
US Margin 13
DS Margin 20
Trained Modulation ADSL_G.dmt
LOS Errors 0
DS Line Attenuation 20
US Line Attenuation 9
Peak Cell Rate 1207 cells per sec
CRC Rx Fast 0
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path
 
Garth Massey said:
What would you say about my line ???

Connection Status Connected
Us Rate (Kbps) 512
Ds Rate (Kbps) 4096
US Margin 13
DS Margin 20
Trained Modulation ADSL_G.dmt
LOS Errors 0
DS Line Attenuation 20
US Line Attenuation 9
Peak Cell Rate 1207 cells per sec
CRC Rx Fast 0
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path
Click to expand...

Those are absolutely excellent stats!

For those that don't know, attenuation is the amount (usually in dB) that the signal strength deteriorates as it propagates from the DSLAM to you. 3dB equates to a halving of the signal strength. So you want this to be a low value. The noise margin is the difference between the actual Signal-To-Noise Ratio (SNR) and the SNR required to run at a specific speed. So if your line required a 30dB SNR to run at 384k, and you actually had a SNR of 47dB, your noise margin would be 17dB.

If you sync at a higher speed, it tends to make your attenuation increase, as more of the higher-frequency part of the spectrum are used. In addition, your noise margin will decrease.

So at the speed at which you sync, you want to have a low attenuation and a higher noise margin. This means that the signal is not deteriorating much as it propagates down the copper to you, and that your SNR is much better than required for the speed at which you are sync'd.

Note, even though your router might report a plethora of different names for noise margin, many of them wrong, it's a pretty good bet that the actual figure is the noise margin value, not a SNR.
 
Kompete said:
Pulled the following info from my router web interface (modem status):

Modem Status
Connection Status Connected
Us Rate (Kbps) 128
Ds Rate (Kbps) 256
US Margin 12
DS Margin 13
Trained Modulation ADSL_G.dmt
LOS Errors 0
DS Line Attenuation 57
US Line Attenuation 31
Peak Cell Rate 301 cells per sec
CRC Rx Fast 1424
CRC Tx Fast 77
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path

DSL Statistics
Near End F4 Loop Back Count 0
Near End F5 Loop Back Count 0
Click to expand...

Telkom techie came out today (quick response ;)); he said that the slow line speed could be as a result of me not having a filter at my line downstairs (where I use my phone), although I have a filter upstairs (where the line connects to my modem) ? Will check tonight if there's any change in my line stats.
 
Kompete said:
Telkom techie came out today (quick response ;)); he said that the slow line speed could be as a result of me not having a filter at my line downstairs (where I use my phone), although I have a filter upstairs (where the line connects to my modem) ? Will check tonight if there's any change in my line stats.
Click to expand...

Dunno if I understand you correctly but the modem/router does not need a filter unless you mean you have a phone upstairs.

My suggestion to you is to disconnect all filters, telephones, faxes, answering maching etc and ONLY connect your router and check what results you get then.
 
ponder said:
Dunno if I understand you correctly but the modem/router does not need a filter unless you mean you have a phone upstairs.

My suggestion to you is to disconnect all filters, telephones, faxes, answering maching etc and ONLY connect your router and check what results you get then.
Click to expand...

Yeah, I mean I have a phone point upstairs (although no actual handset). Will try to disconnect downstairs phone, fax etc, and connect router directly and check results.

tx
 
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