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At what point should I start asking questions...

scootie
Grafter
Posts: 4,799
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Registered: ‎03-11-2007

Re: At what point should I start asking questions...

what upstream sync do you get on adsl2+ g.992.5 ?
Superuser
Superuser
Posts: 9,997
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Registered: ‎06-04-2007

Re: At what point should I start asking questions...

To make use of frequencies above 1.1kHz ADSL2+ needs to be selected. Alternatively if you want to leave it to the router select Multimode which should choose ADSL2+. The noise margin in the first image was 12dB and if that is the target for your line (because it is regarded as noisy/unstable) that will reduce your achievable sync speed by around 1500kbps (perhaps more on ADSL2+).
I suggest you select ADSL2+ (or Multimode) and leave it for a few days to let the DLM reassess your line - that might prompt a reduction in target noise margin - potentially increasing sync speed.
Does your connection have a history of noise and drop-outs?
Almost certainly, as others have suggested you were mistakenly provisioned on a capped-upload service for the 21CN trial.
David
bluetba
Dabbler
Posts: 19
Registered: ‎16-03-2009

Re: At what point should I start asking questions...

I emailed jamesH as suggested and now I have 1mb up!  Smiley
I have messed around with the modulation and found that ADSL2+ 992.5 and multimode both cause my download speed to drop, I was on 4.2 when running on g.dmt but now when set to Multimode or ADSL2+ g.992.5 it drops down to 3.4 (when on multimode it reports that it is using ADSL2 g.992.3).
My line has been very stable well since they replaced the line going from the house to the poll a few years ago, and yes it has always been around 12db although now it is on 14db.
Here are how things stand.....
Community Veteran
Posts: 26,785
Thanks: 985
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Registered: ‎10-04-2007

Re: At what point should I start asking questions...

Have you had confirmation that you will no longer be charged the extra for Max Premium?
(I'd suggest you ask Jameseh to do it as I could easily see an idiot placing an order which took you off 21CN)
jelv (a.k.a Spoon Whittler)
   Why I have left Plusnet (warning: long post!)   
Broadband: Andrews & Arnold Home::1 (FTTC 80/20)
Line rental: Pulse 8 Home Line Rental (£14.40/month)
Mobile: iD mobile (£4/month)
bluetba
Dabbler
Posts: 19
Registered: ‎16-03-2009

Re: At what point should I start asking questions...

Good point will go and check - thanks for mentioning that.
Highlighted
Superuser
Superuser
Posts: 9,997
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Registered: ‎06-04-2007

Re: At what point should I start asking questions...

I'm surprised that Multimode doesn't result in ADSL2+ being selected; is there any Draytek information available that explains the background to the choice?
What minimum SNR do you see in the evening/overnight when the margin is usually at its lowest?
Plusnet have said elsewhere that the 21CN DLM is more responsive so if you leave the connection alone for a few days it is possible that your target noise margin will reduce which should increase sync speed.
The uncapped upstream sync achieved is excellent. Does your router give upstream attenuation and noise margin to go with this?
David
bluetba
Dabbler
Posts: 19
Registered: ‎16-03-2009

Re: At what point should I start asking questions...

I had thought that about the multimode not selecting ADSL2+, I have the 2820 and am really starting to wonder about this router.
I have never noticed that the SNR changes, I will start to keep an eye on it.
I will be leaveing it alone now, I was going to force it on to ADSL2+ but I have done so much messing today I would rather leave it alone - I have just run a BT speed test and now I get 2.4 down.  Cry
Again with the very expensive Draytek 2820 you don't get this info - well not to my knowledge. I do have an unlocked BT 2700HGV or even a SKY router that I can use to see this, I will give it a few days and if it hasn't improved I will plug in the BT router.
bluetba
Dabbler
Posts: 19
Registered: ‎16-03-2009

Re: At what point should I start asking questions...

Found this if it helps....
Superuser
Superuser
Posts: 9,997
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Registered: ‎06-04-2007

Re: At what point should I start asking questions...

The second image gives the information I was seeking, figures reproduced here for convenience:

Mode ADSL2 (G.992.3)
                    DS           US
actual rate         3436kbps     1031kbps
attainable rate     3980kbps     1032kbps
attenuation         42dB         23dB
SNR margin          14dB         6dB
output power        18.2DBm      12.7dBm
path mode           interleave   interleave

The upstream noise margin is 6dB, so that direction is working OK. With downstream attenuation of 42dB a sync around 8000kbps should be possible using ADSL2+ at 6dB noise margin; losing the higher frequencies on ADSL2 will reduce that capability as will the higher noise margin of 14dB, but I'm uncertain of the total effect.
The downstream attainable rate for the connection is stated as 544kbps higher than the actual rate; I'm not sure what this difference represents (tried Google), but I think it might be the sync rate for a smooth bits/bin vs bin number trend. That would imply your line (external and internal) is subject to a fair bit of interference (loss of capability) at some frequencies. Perhaps this is what caused the router to select ADSL2 rather than ADSL2+ when given the Multimode option. However, I emphasise these thoughts are very speculative.
With regard to suitability of the DrayTek 2820 for 21CN - the following quote …
Quote from: Oakey
Before the upgrade I was getting around 5900kbps actual download with a SNR of 12 and Loop Att. of 20. and an IP Profile of 6500.
Since the upgrade, I'm pleased to say that I'm getting around 14000kbps download with a SNR of 8 and a Loop Att.of 28 and an IP Profile of 15000.
Using a DrayTek 2820 router.

… suggests it can work well, and I've no reason to doubt its capabilities.

David
David
bluetba
Dabbler
Posts: 19
Registered: ‎16-03-2009

Re: At what point should I start asking questions...

That really informative thanks for spending the time doing that.
My down speed has so far increased to 4mb and my up is still at 1mb even though it is still reporting ADSL2 - also I am finding browsing the internet "sluggish" even when checking emails it used to go 40.50.60.80.100...complete now it goes more like 60......70...............80.................100........................................................................complete.
bluetba
Dabbler
Posts: 19
Registered: ‎16-03-2009

Re: At what point should I start asking questions...

Hi, I am looking for some more advice, although I think I will now be speaking to support....
It has been 6 days and I have not touched the router until yesterday, over the past week my speed dropped from 4.2 down to around 3.2 and it was still connected using ADSL2 (G.992.3).
Yesterday I rebooted it and it reconnected back at 3.8 but still using ADSL2 (G.992.3). now here's the interesting part - last night I rebooted the router again and left it so I could see what it says this morning and found that it was connected at i think 3.6 but it reported the mode was ADSL2+
Now although I thought it was good that it had connected at ADSL2+ I found that I could not access the internet, it said it was connected but I couldn't get anything. I had noticed last night the PS3 and the Xbox couldn't sign on but unfortunately I couldn't check the ADSL status because I couldn't get to my computer but can only assume that being connected at ADSL2+ meant to internet access at all - in fact I remember this morning that home server server had given me a warning that it couldn't update the live domain.
Here are my line details as of this morning....
Mode ADSL2(G.992.3)
DS                               US
Actual Rate          : 3882000 bps    Actual Rate              : 1045000 bps
Attainable Rate    : 4044000 bps    Attainable Rate        : 1044000 bps
Attenuation          : 40 dB                  Current Attenuation : 23 dB
Cur SNR Margin  : 12dB                    SNR Margin              : 6  dB
Output Power      : 18. 8 dB              Output Power            : 12. 6dB
Path Mode            : Interleave            Path Mode                : Interleave
I am right in saying that it should be connected using ADSL2+ and that if it cant then there must be a problem with my line?
Thanks in advance
Chris