Kitz Forum

Broadband Related => ISPs => Topic started by: Bap on January 19, 2007, 09:33:29 PM

Title: BT Issues
Post by: Bap on January 19, 2007, 09:33:29 PM
New here, though i have used the site for a long time for this and that, very useful :D

Anyway, i've had BT for quite some time and after i upgraded 8mb dsl max my latency sky rocketed, i requsted a few days ago for interleaving to be turned off but i was just wanting to know if someone could look at my router stats (below) and tell me if anything is out of the ordinary.

Thanks in advance, and i look forward to hearing from you. (Router = Linksys WAG35G)

ADSL Line Type                                  GDMT
ADSL Line CodingADSL Line Coding    INTERLEAVED
Line Attenuation                                 (Down):34  (Up):16
Noise Margin                                           (Down):7  (Up):21
Total Output Power                              (Down):0  (Up):0
Current State                                          DownStr: 3712(K)  UpStr: 448(K)
undefined                                            UP
FEC(FAST)                                            (Near):0  (Far):0
FEC(INTERL)                                          (Near):408  (Far):106974
CRC(FAST)                                           (Near):0  (Far):0
undefined                                            (Near):9  (Far):73
HEC(FAST)                                           (Near):0  (Far):0
HEC(FAST)                                           (Near):204  (Far):0
Showtime last(sec)                              10936
ADSL FW Version                              0.49
ADSL Board Type                              Annex A
Title: Re: BT Issues
Post by: mr_chris on January 19, 2007, 10:15:50 PM
Hiya Bap, and welcome to the forum.

First of all, you're right in that Interleaving has caused your latency to go up, and to be honest, turning off Interleaving will probably put that back down to normal. Is your actual download speed ok?

However one thing that I have spotted is that your sync rate of 3712 is really quite low for a 34dB attenuation line - my own line has 39dB of attenuation and I sync at 7712kbps, or the full 8128 depending on time of day.

Have you tried the router plugged straight into the BT master socket, or even better, plugged into the test socket behind the master faceplate. Some more info here ( :)
Title: Re: BT Issues
Post by: Bap on January 19, 2007, 11:14:10 PM
Yeah i have tried connecting it to the test socket, same thing, i have contact BT numerous times about this and they just say "Its your area it has high usage" even though my friends the same distance from the exchange (600meters) and he connects at 6.5mb

BT just ignore me, i was contemplating taking my case straight to Ofcom and making a complaint, even when i sent a complaint to BT, their compaints desk said sorry this isnt a complaint this is a technical issue, then they send me mumbo jumbo about line tests where fine.

Cant wait till my contract runs out :D
Title: Re: BT Issues
Post by: kitz on January 19, 2007, 11:52:37 PM
Hi Bap and welcome.

>> "Its your area it has high usage"

Unfortunately that is something that Ive seen BT use before now.. and in actual fact is very wrong :(
How busy your exchange is has no bearing what-so-ever on what speed your router syncs to the exchange at.

>> FEC(INTERL)  (Near):408  (Far):106974

TBH I am a tiny bit concerned at what effect switching interleaving OFF on your line could have.  I notice that the router has only been switched on a couple of hours but interleaving seems to have been working away and correcting errors on your line.
Its therefore only fair that I point out that turning interleaving off therefore may affect the stability/speed of your line.

>> distance from the exchange (600meters)

That attenuation is very high even allowing for additional BT routing and  Im really not happy about that attenuation figure if your line really is that short.
Atten could be internal wiring/equip, aluminium on the joints, line fault.
In view of the fact you say youve already tested from the test socket.. the next thing I would do if I were you would try another router.  Is it possible to borrow your friends router for an hour to see what stats you get when using that.

>> Total Output Power  (Down):0  (Up):0

This is strange but could be a router firmware issue.
Title: Re: BT Issues
Post by: Bap on January 20, 2007, 12:18:45 PM
I have tested two routers, same stats, i think its an internal wiring fault, but bt just keep saying theres nothing wrong, this and that.
Title: Re: BT Issues
Post by: kitz on January 21, 2007, 04:58:56 PM
>>  i think its an internal wiring fault,

If you've tested from the test socket from behind the master socket, then that should rule out that possibility.
Title: Re: BT Issues
Post by: Bap on January 22, 2007, 01:28:11 PM
Here is another weird problem, look at my sync speeds on my router (below)

DSL Status :       Up           
               DSL Modulation Mode :      GDMT         
               DSL Path Mode :      INTERLEAVED         
               Downstream Rate :      5216 Kbps         
               Upstream Rate :      448 Kbps         
               Downstream Margin :      11 db         
               Upstream Margin :      22 db         
               Downstream Line Attenuation :      34         
               Upstream Line Attenuation :      16

But then look at my speed tests (below)


Speed Test Results
Date    22/01/07 13:22:46
Speed Down    2312.10 Kbps ( 2.3 Mbps )
Speed Up    370.15 Kbps ( 0.4 Mbps )

BB Max speed test

Last Result:
Download Speed: 2373 kbps (296.6 KB/sec transfer rate)
Upload Speed: 374 kbps (46.8 KB/sec transfer rate)
Title: Re: BT Issues
Post by: mr_chris on January 22, 2007, 02:09:57 PM
Hiya there

Not sure if you're aware, but as well as your sync rate, there's something called an IP profile, sometimes referred to as a "BRAS" (broadband remote access server) profile - which limits your connection rate through the BT network.

If you've been synced at a lower speed, your IP profile will drop accordingly... but here's the bummer - if you sync back up at a higher speed, you have to maintain that for at least 3 days before your profile speed will increase again.

There's a table listing sync speeds vs profile speeds here (

So given you were connected at 3712kbps the other day, that equates to an IP profile of 3000kbps. I'd guess, given your screenshots, that you've actually connected lower than that at some point too, and your IP profile has been set to 2500kbps, which would tie up with those speedtests.

In 3 days time, if you manage to maintain a higher sync rate, your actual speeds should start to improve... hopefully!
Title: Re: BT Issues
Post by: Bap on January 23, 2007, 12:14:48 AM
The joys of BT, cant wait to get my 10mb ntl, thanks for the help people!