Topic: What is line profiling?

[Clive]

Another question for Rik methinks.  I've recently been suffering slow speeds and BT have even dug cables up in my street.  They found that two cables were touching each other but rectifying that fault made no difference at all.   They then said that they would get the exchange to increase my line speed which is what I asked for in the first place! They did this but again that made no difference.  Next they told me that they had to reprofile my line and within hours my speed increased tenfold.  However, after a feedback call a couple of hours ago the speed is already getting much slower and has collapsed to just 1 meg.  What is going on? 

[Simon]

Rik, as you say, will explain it, Clive, but you can get your profile by performing a BT Speedtest.  It may require some perseverance to get it to work, but unfortunately, this is the only line tester that will reveal your profile.

[Rik]

Is your router dropping the connection at intervals, Clive?

[Clive]

It was when the problem first began when I returned from London.  But after my first phone call to BT the router stayed connected.  Coincidence?  Thanks for the link Simon.  I will try it out. 

[Clive]

These are my results:

Test1 comprises of Best Effort Test:  -provides background information.
    Your DSL connection rate: 4000 kbps(DOWN-STREAM),  448 kbps(UP-STREAM)
    IP profile for your line is - 3500 kbps
    Actual IP throughput achieved during the test was - 3127 kbps

If you wish to discuss these results please contact your ISP.

If you are experiencing problems with specific applications, servers or websites please contact your ISP for assistance.

Your test has completed please close this window to exit the performance tester.


The ISPReview speedtester claims it is 2778 kbps which is slightly slower.  However a retest shows that the speed varies considerably.

[Simon]

Right, I don't really know what I'm talking about, Clive, but to echo what I've heard before, your throughput seems a little low for the profile, but not dramatically so, and to be honest, that speed is not too bad really.  Rik won't be here now till the morning, but I think the next thing he would ask for is your router stats, which should give an indication of what your speeds should be.

[Clive]

Router says: 

Broadband connection details:
 
Downstream  4,000 Kbps
 
Upstream  448 Kbps
 
Connection time  1 day, 20:37:00 

Data transmitted  42.40 MB 
 
Data received  189.13 MB
 
 
 

[Simon]

There should be more stuff, like SNR margins, attenuation, etc.  That's the meat for the two veg! 

[Clive]

I don't know where to find that information Simon.   

[TR]

Clive like you? this last week I have suffered below par performances with BT broadband 

Dear Mr.*******,

Thank you for your e-mail dated 14th November '08. It has been logged under the reference number VOL011-14********.

I am sorry to learn from your email, you are experiencing an issue with the slow broadband speed. I apologise for the inconvenience caused as this is an ongoing issue. I understand the importance of the stable broadband connection.

However, I would like to inform you that I have checked the previous records and interactions which states that your case has been escalated to the higher level of department for advanced troubleshooting. They are dealing with the issue at present. They will contact you very soon.

That was from Mr Sing 

I have logged my line speeds with ADSL Thinkbroadband for 2 years 

Graph below:

[Simon]

I don't know where to find that information Simon.   

Not sure what router you have, Clive, but it's probably time to hand over to Rik anyway. 

[Clive]

That graph says it all Terry!  My speed has rarely been anywhere near as high as yours but I'm quite happy with 3 - 4 Mb.  I'm now back up to 3.3Mb so I will see how long that lasts.  I use a relatively new Home Hub Simon.

[Clive]

I've found the information Rik might need Simon.

DSL Connection 

Link Information
   
 
Uptime: 1 day, 22:48:25
 
Modulation: G.992.1 annex A
 
Bandwidth (Up/Down) [kbps/kbps]: 448 / 4,000
 
Data Transferred (Sent/Received) [MB/MB]: 47.68 / 229.63
 
Output Power (Up/Down) [dBm]: 11.5 / 19.0
 
Line Attenuation (Up/Down) [dB]: 25.0 / 41.0
 
SN Margin (Up/Down) [dB]: 24.0 / 15.0
 
Vendor ID (Local/Remote): TMMB / ALCB
 
Loss of Framing (Local/Remote): 0 / 0
 
Loss of Signal (Local/Remote): 0 / 0
 
Loss of Power (Local/Remote): 0 / 0
 
Loss of Link (Remote): 0
 
Error Seconds (Local/Remote): 0 / 0
 
FEC Errors (Up/Down): 0 / 3,675
 
CRC Errors (Up/Down): 0 / 25
 
HEC Errors (Up/Down): 0 / 24
 
Line Profile: Interleaved
 
 
 

[Simon]

That would be it, Clive.  Let's see what he makes of it. 

[Sandra]

I notice that you have a rather high Line Attenuation and SN Margin Clive, so I assume that you are quite a way from your exchange.
Maybe you wont get much better than you get now without getting an unstable connection.
These are my router stats, just had to reboot it so not connected long.

Uptime: 0 days, 0:14:36
 
Modulation: G.992.5 Annex A
 
Bandwidth (Up/Down) [kbps/kbps]: 1,395 / 16,579
 
Data Transferred (Sent/Received) [MB/MB]: 2.33 / 1.85
 
Output Power (Up/Down) [dBm]: 12.0 / 18.5
 
Line Attenuation (Up/Down) [dB]: 15.5 / 29.5
 
SN Margin (Up/Down) [dB]: 4.0 / 3.5

Have you tried a "Quiet Line Test" ?

Unscrew the 2 screws from the lower part of the master phone socket and plug a standard analogue, wired phone directly into the socket that is now exposed.
Dial 17070 and press the number for the quiet line test when asked. I think its option 2.
You should hear a perfectly silent line without any clicks or crackles. All you should hear is the automated voice saying Quet Line Test every so often. Any other noise and there is a fault on the line between your master socket and the exchange, which will cause you to lose speed and possibly cause disconnections.