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21CN 'Upgrade'

mininut
Dabbler
Posts: 11
Registered: ‎07-08-2007

21CN 'Upgrade'

Upgraded to 21CN yesterday and my speeds have dropped. It was previously pretty solidly 3.7Mbps download with an SNR of 7dB. It's now 2976Kbps download with an SNR of 12dB. I thought that the target SNR for ADSL2+ was 6dB. Any ideas?
Phil
10 REPLIES
JayG
Pro
Posts: 999
Thanks: 91
Fixes: 3
Registered: ‎30-10-2011

Re: 21CN 'Upgrade'

If you only switched to ADSL2+ yesterday the DLM is probably still "thinking" about the best sustainable settings for your connection, and in any case you won't get anywhere trying to report a fault until the "10 day training period" is over (unless it conks out completely!)
I believe that the DLM will at some point aim for a 3dB SNRM on ADSL2+, but whether that will happen with your line depends on your attenuation/quality parameters.
I would try a disconnect via the router interface followed by a reboot/reconnect in a day or so to try for a better sync, but don't keep doing it or the DLM might interpret it as line problem and slow it down even further.
Make sure that your IP profile (as reported by the BT diagnostic speedtester) and your Plusnet profile (in your Account details) are more or less aligned.
Community Veteran
Posts: 4,890
Thanks: 129
Fixes: 24
Registered: ‎14-07-2009

Re: 21CN 'Upgrade'

In my opinion the DLM may be thinking but it has thought wrong!  However Plusnet will not intervene during the training period so you will just have to wait it out.
Community Veteran
Posts: 2,324
Registered: ‎01-08-2007

Re: 21CN 'Upgrade'

Can PN adjust your IP profile if it gets stuck during the training?
Are there any ill effects of not having your IP profile updated by PN during the training period?
Thinking about it as I type - if PN hold my IP Profile at 7.15mb while the exchange keeps trying ever higher sync rates, could this result in a faster connection at the end - i.e. DSLAM tries 12mb, I dont get disconnected or lots of errors, as my data is only being allowed through at 7.15 by PN.  So DSLAM tries 13mb, same result - and so on...  until the training period ends, Im synced at 24mb, and have a PN profile of 7.15mb.  Then I ask pn to update the ip profile, and hey presto a 24mb connection - albeit probably one full of errors and disconnects that werent picked up during training due to the stuck IP profile at the time  Grin
Plusnet Alumni (retired) chrispurvey
Plusnet Alumni (retired)
Posts: 5,369
Fixes: 1
Registered: ‎13-07-2012

Re: 21CN 'Upgrade'

You have an initial 10 day training period, so your speeds may fluctuate during that period. I'd suggest waiting until your training period has finished(07/10/12). We would not be able to raise this as any fault anyway at the moment as you're in your training period. You will hopefully see that you speeds have increased by that point anyway.
Let us know how you get on.
mininut
Dabbler
Posts: 11
Registered: ‎07-08-2007

Re: 21CN 'Upgrade'

Not much change I'm afraid. I've just done a router reboot and these are all the figures:
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
  Running Mode            : ADSL2+(G.992.5)      State                : SHOWTIME
  DS Actual Rate          :  2871910 bps  US Actual Rate      :  1103823 bps
  DS Attainable Rate      :  2852000 bps  US Attainable Rate  :  1104000 bps
  DS Path Mode            :        Fast    US Path Mode        :        Fast
  DS Interleave Depth    :        1      US Interleave Depth  :        1
  NE Current Attenuation  :      42 dB    Cur SNR Margin      :      12  dB
  DS actual PSD          :    17. 1 dB    US actual PSD        :    12. 5  dB
  ADSL Firmware Version  : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
  Far Current Attenuation :      21 dB    Far SNR Margin      :        6  dB
  CO ITU Version[0]      : 00004946      CO ITU Version[1]    : 0000544e
  DSLAM CHIPSET VENDOR    : < IFTN >
Plusnet Alumni (retired) chrispurvey
Plusnet Alumni (retired)
Posts: 5,369
Fixes: 1
Registered: ‎13-07-2012

Re: 21CN 'Upgrade'

I've placed a SNR reset on your line, this normally takes 4 hours to complete but it may need leaving until the morning.
Hopefully this will solve the issue for you, if not then we can raise a fault tomorrow.

mininut
Dabbler
Posts: 11
Registered: ‎07-08-2007

Re: 21CN 'Upgrade'

Chris thanks very much. I've just checked and the result is:
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
  Running Mode            : ADSL2+(G.992.5)      State                : SHOWTIME
  DS Actual Rate          :  4663944 bps  US Actual Rate      :  1131857 bps
  DS Attainable Rate      :  4772000 bps  US Attainable Rate  :  1132000 bps
  DS Path Mode            :        Fast    US Path Mode        :        Fast
  DS Interleave Depth    :        1      US Interleave Depth  :        1
  NE Current Attenuation  :      44 dB    Cur SNR Margin      :        6  dB
  DS actual PSD          :    19. 1 dB    US actual PSD        :    12. 6  dB
  ADSL Firmware Version  : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
  Far Current Attenuation :      21 dB    Far SNR Margin      :        6  dB
  CO ITU Version[0]      : 00004946      CO ITU Version[1]    : 0000544e
  DSLAM CHIPSET VENDOR    : < IFTN >
Looking better but everyone else I know on ADSL2+ has an SNR of around 3dB. Do I just need to have a bit more patience?
Phil
Plusnet Alumni (retired) chrispurvey
Plusnet Alumni (retired)
Posts: 5,369
Fixes: 1
Registered: ‎13-07-2012

Re: 21CN 'Upgrade'

How's everything performing for you at the minute?
It's looking good from our side.
mininut
Dabbler
Posts: 11
Registered: ‎07-08-2007

Re: 21CN 'Upgrade'

Looking reasonable thanks. SNR is 6dB for most of the time but occasionally drops to 4dB so I guess it's about spot on for ensuring reliability. And I'm getting a little bit more download and a lot more upload than I was before the upgrade so no complaints. Thanks for your help Chris.

Phil
P.S. Any chance you could wave your magic wand and deliver me FTTC or FTTP?  Wink
Plusnet Alumni (retired) chrispurvey
Plusnet Alumni (retired)
Posts: 5,369
Fixes: 1
Registered: ‎13-07-2012

Re: 21CN 'Upgrade'

I wish, I'd have waived it outside my house if I could  Shocked
Glad speeds are better for you, if there's anything else then please let me know.