LLU

Hi was just wondering if LLU was better for longer lines i am currently on max and live a long way from the exchange

syncd at 2,5
download at 2

if i was on LLU would i get better speeds

Unlikely Tiscali LLU uses a higher default noise margin at 9dB, so if getting 2.5Mbps sync with 6dB margin, your sync is likely to lower.

Andrew

on PlusNet's LLU service, the min SNR is actually 12dB both up and down so your sync rate will be lower still.

I am trying to get PN to get Tiscali to offer 9db and 6dB profile options but for reasons unknown to me, this has not yet happened, although I know PN were talking to Tiscali about it.

That's all news to me guys, thanks.

I was tempted to ask to be switched to LLU but according to my Netgear router my SNR rarely gets much above 7 !!!

Sky would be tempting when Easynet/Sky eventually enable my exchange and I understand their default SNR is 6. In this case ie line matching default SNR, would switching to LLU improve connection/sync ??

Maybe from 2.5 to 2.6, then allow for overheads, back down to around 2.2Mbps, so perhaps a 10% increase in speed, nothing major at all.

Andrew

If you have a DG834v2, v3 (firmware > 1.05.00) or DG834GT (any firmware), then don't beleive what the router is saying for SNR because it gets very confused!!!

There is an on-going investigation on the PUG forum by several members on why SNR varies so much on the netgear when other routers see only 1 or 2 dB difference rather than the major swings the netgear sees, which can also cause sync loss forced by the router.

Ok.

That makes sense ... I have the 834 v2 (f/w 3.01.25) and the SNR can go from 5 down to 1 back up to 6 in a matter of seconds.

I also occasionally use a SAR715 which shows the SNR at a steady 6/7 at all times.

Edited by AdamBrunt (Tue 07-Nov-06 22:40:42)

speedtester.bt.com has just this minute come back with the following results:

Test1 comprises of Best Effort Test:
IP profile for your line is - 5000 kbps
DSL connection rate: 448 kbps(UP-STREAM) 6336 kbps(DOWN-STREAM)
Actual IP throughput achieved during the test was - 4284 kbps

I am not sure where you're getting your 2.5/2.6 from ??

I think Saffy was getting confused with your line stats and the OP who had 2Mb stats. It's been a long day for him on here

Thought tha would be it ... but just thought I'd check to make I'm not missing anything

I suspect it may be real this variation, and is down to how the GT populates the bins and calculates the margin perhaps.

Certainly I do see connection problems if margin drops into the 1-3 area.

Andrew

With a 7dB margin, then since Tiscali LLU uses a 12dB target margin, your sync speed may almost half.

So what you gain from loss of BRAS Data Rate may be lost to the higher margin

Andrew
Oh and I was reading in flat mode, and missed that you were not the OP - long day, and not just this place

Edited by MrSaffron (Wed 08-Nov-06 09:59:52)

Thanks for that Andrew.

So, if at some point in the future I moved to Easynet/Sky (whose default, apprently, is 6db) - what *should* the effect be then ??

A minor change, maybe an extra 128Kbps but a bit more of a gain from no BRAS Data Rate

If it is ADSL2+ you get, you may get a bit more speed too.

Andrew

Not from our findings Andrew.

Using other routers on the same line show very little variation on reported SNR values and usually no disconnections - we have tried vigors, d-links and a few others I can't remember, all showing a rock steady SNR value. In the case of a DG834, firmware versions 1.05.00 shows very little change in SNR, but upgrading to 2.10.10 or 3.01.25 on the same line on the same router show wildly varying SNR values.

This is not down to line conditions, its a fault in later firmware versions but we have yet to convince Netgear to investigate further. We have managed to get past 1st line support to 2nd line support in the UK but since then no word from them.

This is also affecting many people on different lines / exchanges and suppliers (BT & LLU). It appears to be more prevalent on lines > 2Mbs speeds which is probably why this was not noticed pre-Max.