http://www.coolwebhome.co.uk/calc/calculator.php

Now gives 9db, 6dB and 3dB figures
9dB 9119 Kbps
6dB13309 Kbps
3dB 19424 Kbps

But looking at the error stats I'd be very shocked it performed that well down at 3dB target margin, errors may negate the extra sync speed, or make it too unstable.

Upstream is usually better under WBC compared to Sky LLU due to the DLM

1. Lines with a reasonable speed expectation are not capped.

2. Getting the cap removed is usually very easy.

In reply to a post by jelv:

1. Lines with a reasonable speed expectation are not capped.

2. Getting the cap removed is usually very easy.

Thanks for that info jelv

PN sales gave me a different story a few weeks ago - guess I must have been talking to the wrong person!

Did you get it sorted? If not post your stats (sync speed, attenuation and noise margin) and we'll see if there is a reason they said no.

In reply to a post by jelv:

Did you get it sorted? If not post your stats (sync speed, attenuation and noise margin) and we'll see if there is a reason they said no.

No didn't get it sorted, I only gave them my phone number and post code.

Quoted estimated line speed was 8Mbps, but when I asked about the upstream sync a cap of 448K for 21CN appeared to be all that they could offer unless it needed un-capping due to any technical issues - or something like that

Current partial LLU stats (uno SMPF):

Uptime: 9 days, 6:38:48

DSL Type: G.992.5 annex A

Bandwidth (Up/Down) [kbps/kbps]: 1.022 / 13.107

Line Attenuation (Up/Down) [dB]: 21,0 / 37,0

SN Margin (Up/Down) [dB]: 10,5 / 6,5

Interleaved.

Downstream throughput always ~11Mbps

......................................................................................

Previous adsl1 stats from last year (PN extra + pro):

Bandwidth (Up/Down) [kbps/kbps]: 832 (upstream uncapped) / 8128

Line Attenuation (Up/Down) [dB]: 20.5 / 34

SN Margin (Up/Down) [dB]: 9 / 9.5

Interleaved.

IP 7000K - downstream throughput was usually ~6500K


Reason for my enquiry was because my exchange has recently been upgraded to 21CN and a switch from uno partial LLU to PN might save a few quid.

Looking at those stats I'd be surprised if they capped you and if they did there would be no issue getting it uncapped. There was misinformation circulating some time ago about uncapping upstream slowing downstream (confusion with Annex M?) and there is a slight possibility on very long lines that might be true.

Don't think I want to take a chance with PN and their ticketing system just yet - unless the upstream sync is uncapped from the onset, which xilo/uno do with 21CN, think I'll stay with uno SMPF a bit longer. In the mean time I'll check how 21CN is performing at my exchange and since it's a Market 2 exchange Plusnet might be a good choice in the future.

Thanks for your help jelv

In reply to a post by 4M2:

.... In the mean time I'll check how 21CN is performing at my exchange and since it's a Market 2 exchange Plusnet might be a good choice in the future.

?
Only individual ISP performances are relevant. Except in very exceptional circumstances performance on BT Wholesale products is a function of the ISP end, not the exchange end.

Bob,

Relative to previous adsl1 performances a few folks who have gone to 21CN adsl2+ at my exchange are unfortunately somewhat disappointed with their sync speeds despite only slight increases in attenuation and SNRM's being good - would that only be ISP related?

I'd say it was quite normal given the lack of knowledge of the general public about what they should be getting on ADSL(1) and how to improve it. Even how to find out is not common knowledge. Just subjective experience of how quickly web pages load. Which anyway is largely connection-speed independent below 8Mbps.

Anyone connecting below 6Mbps on ADSL, which I guess is the majority, is not going to get any significant downstream improvement on ADSL2+. They will gain on upstream.

See this graph, which is a good, though not infallible, guide.

We get large numbers of posters here who we are able to raise from around "average" to near the maximum. When estimating ADSL2+ from ADSL using it, the possible attenuation increase of 3dB has to be considered.