On O2/Be LLU one expects around 84% of sync as throughput. The new WBC DLM gives an instantaneous 88.2% profile, then there's the TCP/IP overheads to take out. Not much difference overall I expect.

Then there is the frequent 3dB sync-time margin on WBC, (and available on some O2/Be packages but not TT so far as I know), which can make 1200kbps sync difference.

In reply to a post by RobertoS:

On O2/Be LLU one expects around 84% of sync as throughput. The new WBC DLM gives an instantaneous 88.2% profile, then there's the TCP/IP overheads to take out. Not much difference overall I expect.

I was given the impression, perhaps wrongly, that TT exchange kit (in my case probably ex-Tiscali broadcom kit and uno SMPF) would give a slightly faster downstream sync than 21CN WBC kit with the same 37bB attenuation and 6dB SNRM using a broadcom router, i.e. tg585v7.

It would probably be wrong to generalize that TT LLU would be faster than WBC adsl2+ though?

Edited by 4M2 (Tue 28-Aug-12 13:57:55)

Sky DLM can now set a sync that gives a 3db SNR too.

A few years ago talktalk may have been slightly faster due to the way the systems used to work.

Nowadays they should work out about the same. If anything BTs would be quicker as it's more likely to give you a 3db SNR by default.

That being said with TT you can always request a 3db SNR. So ultimately both would probably be around the same with a slight difference but nothing significant.

Edited by ukhardy07 (Tue 28-Aug-12 14:10:40)

Sure, but how much would downstream throughput be effected by the different systems if using a 6dB SNRM interleaved connection for stability without considering the possibility of a 3dB downstream SNRM?

Again TT and BT 21CN should be around the same. BT perhaps slightly slower but the expected throughput speeds for LLU connections is around 80 - 85% and the BT profiles are in the high 80s.

So throughput wouldn't be miraculously better on TT. Throughput is dependant on so many things...

Edited by ukhardy07 (Tue 28-Aug-12 14:26:06)

In reply to a post by ukhardy07:

...So throughput wouldn't be miraculously better on TT. Throughput is dependant on so many things...

using a broadcom router, i.e. tg585v7.

Matching the equipment may give a slightly better speed. You can do this on ANY isp though. So matching the equipment on a sky, BT etc connection may give a better speed. I personally found it didn't make any difference when I tried though.

It would probably be wrong to generalize that TT LLU would be faster than WBC adsl2+ though?

Short answer yes.

As ukhardy and others are saying, the BT WBC product is much different from what it was a couple of years ago. Just the fact hasn't escaped the huge sandbank of its lousy past.

There's a limit to the accuracy anyone can estimate sync speeds on the same line with different equipment and/or different ISP backhaul and routers at their end. There isn't likely to be much difference based on generalities. Just sometimes one hardware combination hits the jackpot on a given line, but forecasting that is an occult art.

Much more important are the ISP's routers, backhaul, and overall throughput capacity.

The last place I ever expected to be was Plusnet! Well - maybe not quite. BT I rated lower, but it was a very close thing between PN and BT when I left IDNet fibre. TT I would be very unlikely to go to but can no longer really give logical reasons. Sky I would also resist because of the dominance established over TV from buying the rights to football many years ago and the deletorious effects of that on many aspects of our culture.

Well I get ~85% of downstream sync as throughput, i.e. 13Mbps and 11Mbps, with a 37db attenuation, interleaved and 6dB SNRM using a TT (uno) SMPF connection. If I were to change to 21CN WBC and retain the same tg585v7 router I would certainly hope not to lose too much throughput with a 6dB SNRM - of course a 3dB downstream SNRM might be possible with WBC adsl2+ but unlikely on my line...