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Max DSL subscriber lost speed when moved to 21CN - help.

YBH
Dabbler
Posts: 16
Registered: ‎03-04-2010

Max DSL subscriber lost speed when moved to 21CN - help.

Hi first post. I have recently been migrated to 21CN (not my choice) and it appears since that day, my speeds (usually 3.5mb) have dropped significantly to 1.8mb. I have raised two faults with the Plusnet team and have tried a number of options (disconnecting other equipment, using master socket, new micro filters, new router), all without any change. I have asked plusnet to move my service back to the old infrastructure to recover my lost speed - they advised this would take 6 weeks. V frustrated. router stats as below. Any one suggest anything - apart from moving elsewhere (which i dont really want to do). thanks for your help. ybh
Thomson TG585 v7

Uptime: 0 days, 22:07:05
DSL Type: G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]: 448 / 2,048
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.5 / 18.0
Line Attenuation (Up/Down) [dB]: 31.5 / 50.0
SN Margin (Up/Down) [dB]: 15.0 / 16.0
Vendor ID (Local/Remote): TMMB / TSTC
Loss of Framing (Local/Remote): 12 / 0
Loss of Signal (Local/Remote): 1 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 1 / 0
FEC Errors (Up/Down): 0 / 1,710
CRC Errors (Up/Down): 0 / 74
HEC Errors (Up/Down): 0 / 66
9 REPLIES 9
spraxyt
Resting Legend
Posts: 10,063
Thanks: 674
Fixes: 75
Registered: ‎06-04-2007

Re: Max DSL subscriber lost speed when moved to 21CN - help.

It looks like your downstream target noise margin might well have increased to 15dB, and that will have led to your sync speed reducing by 1500kbps or more. The cause of increased target noise margin is typically lots of disconnections, or lots of transmission errors. Have there been problems on either/both of these fronts?
The 21CN DLM seems more responsive than the equivalent on 20CN, and leaving your router connected 24x7 for perhaps 7 days might cause the DLM to reduce the target noise margin, giving you an increased sync speed. The router will re-sync of its own accord if that happens so there is no need to reboot 'just in case'.
In fact the increased responsiveness of the DLM seems to be a two-edged sword, it is far too ready to increase target noise margin at the slightest excuse.
David
YBH
Dabbler
Posts: 16
Registered: ‎03-04-2010

Re: Max DSL subscriber lost speed when moved to 21CN - help.

Hi, thanks for the reply. in the recent past i have had a lot of disconnections (plusnet suggested it was possibly my router a Linksys WA54G and sent me a thompson replacement). Since then the disconnections have stopped it appears, but the speed is the same. how often does DLM review the line ? (how long should i give it?). Thanks....
itsme
Grafter
Posts: 5,924
Thanks: 3
Registered: ‎07-04-2007

Re: Max DSL subscriber lost speed when moved to 21CN - help.

Quote from: YBH
Thomson TG585 v7

Uptime: 0 days, 22:07:05
DSL Type: G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]: 448 / 2,048
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.5 / 18.0
Line Attenuation (Up/Down) [dB]: 31.5 / 50.0
SN Margin (Up/Down) [dB]: 15.0 / 16.0
Vendor ID (Local/Remote): TMMB / TSTC
Loss of Framing (Local/Remote): 12 / 0
Loss of Signal (Local/Remote): 1 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 1 / 0
FEC Errors (Up/Down): 0 / 1,710
CRC Errors (Up/Down): 0 / 74
HEC Errors (Up/Down): 0 / 66

DSL Type: G.992.1 annex A = ADSL1. Question to ask PN is have you been placed on 21CN with a fixed speed?
scootie
Grafter
Posts: 4,799
Thanks: 1
Registered: ‎03-11-2007

Re: Max DSL subscriber lost speed when moved to 21CN - help.

what package are you on? as value is capped to adsl (g.dmt) you need to be on preminum or pro to get adsl2+
YBH
Dabbler
Posts: 16
Registered: ‎03-04-2010

Re: Max DSL subscriber lost speed when moved to 21CN - help.

Hi,
yep - i'm on value package - which is fine for me (given the best i could get on adsl was 3.5mb plus allowance was good for me). Reason why i didn't upgrade to other packages is because I didn't expect any difference in speed if I moved to ADSL2+ plus I wouldn't use the new allowance....
are you saying that to get back my original speed i need to move packages to an adsl2+ package (Premium/Pro)......? Surely Max DSL will work ok on the new infrastructure? Confused....
spraxyt
Resting Legend
Posts: 10,063
Thanks: 674
Fixes: 75
Registered: ‎06-04-2007

Re: Max DSL subscriber lost speed when moved to 21CN - help.

Quote from: YBH
… in the recent past i have had a lot of disconnections (plusnet suggested it was possibly my router a Linksys WA54G and sent me a thompson replacement). Since then the disconnections have stopped it appears, but the speed is the same. how often does DLM review the line ? (how long should i give it?). Thanks....

It's probably those disconnections that have led to the target noise margin being increased. Now that they have stopped the target should come down again once the DLM is convinced the line is stable. Leaving the router connected 24x7 is the best way to demonstrate that.
I think the DLM reviews line performance at least every 24 hours and can change interleaving depth and target noise margin at any review. How long one has to wait is indeterminate, shorter periods when the line is being actively managed, longer periods once in a stable state. I was hoping your use of the word "recently" in your opening post suggested a shorter period might apply in your case. With fingers crossed I suggested 7 days, but that was speculation. It could be 3 days or could be 14 days, but could be more.
The one thing that seems certain on 21CN is that trying to help by restarting the router generally proves counter productive and the DLM reacts faster if left to its own devices.
Others have mentioned the possibility of trying to move to ADSL2/ADSL2+. From your preceding post I think you've already checked this but with 50dB attenuation on your line (around 3.5km line length from the exchange) any benefit from ADSL2 will be small (200 to 300kbps increase in sync speed, albeit perhaps enough to move you up one IP Profile step). In my opinion that is something to consider in the future if your usage pattern changes to warrant it, the Value package is fine for the present and your sync speed should recover just as well with that package as with the more costly ones.
David
scootie
Grafter
Posts: 4,799
Thanks: 1
Registered: ‎03-11-2007

Re: Max DSL subscriber lost speed when moved to 21CN - help.

am un sure how they deal with switching people to 21cn on request why on value.
If they have moved you to 21cn and fixed your line to sync on adsl (g.dmt) then your not getting any sync benfits and in your case your losing sync speed because your hooked up to the 21cn DLM which as spraxyt says its more responsive than 20cn dlm but will all so head for the hills at the first sign of trouble and trust me the 21cn dlm gets scared very easy.
the options i see for you are
1. move to preminum or pro and get them to move you to adsl2+ and also make sure they uncap the upload sync as well.
2. try and get PN to get you back on max dsl 20cn. Which i very much doubt they will do. it was heard of during the trail days (with alot of fuss from the customer) but dont know what there stance is now days
3. check all your internal wiring setup ect and sit tight and hope the 21cn dlm is good to you.
There was a trail of new options to fix your NM and banded profiles on 21cn but unsure if that is/ or when/ or if ever that will be released as a final product by BTw
question for those in the know.
on value 21cn is it possable to have the upsync uncapped. i know during the trail i forced a few g.dmt sync's and got a upsync around 800kbps
YBH
Dabbler
Posts: 16
Registered: ‎03-04-2010

Re: Max DSL subscriber lost speed when moved to 21CN - help.

thanks both. Any of the plusnet team monitoring this forum have a view as per above. Do i need to do anything now or do i just wait? (and how long do i wait)? thanks
YBH
Dabbler
Posts: 16
Registered: ‎03-04-2010

Re: Max DSL subscriber lost speed when moved to 21CN - help.

anyone?