Likely Speeds for LLU

My exchange (so far only ADSLMax) now appears to have TalkTalk LLU on it. I would be probably considering a reseller option based on SMPF to safeguard flexibility for the future. What speed might I expect?

For the existing ADSLMax service (Titan/Obit Surfwise) the modem stats are
Down 5120 kbps, Line Att down 24.5 dB, Noise margin down14.5 dB
Up 448 kbps, Line Att up 10.5 dB, Noise margin up 21 dB.

It is overhead copper wire and the actual line distance from the exchange is 1.6km.

Speed testers currently report 4407 kbps Down, 357 kbps Up. It's been consistently like that for a couple of months now although it was achieving (according to the speed testers) 5500-6000 kbps over the summer.

Hard to say. With your attenuation of 24.5 you should be getting the maximum 8Mbps sync on standard ADSL rather than the 5120 kbps you are getting. The elevated target noise margin of 14.5 dB indicates a noise problem with your line.

Given your attenuation you'd normally expect > 14Mbps on LLU (ADSL2+). However, without knowing why your target noise margin is raised it's anyone's guess what you'll actually get.

Thanks John2007

Regarding the noise margin. About 18 months ago there was a lot of noise and crackle on the line, BT Openreach came out, fixed a bad connection on the nearest pole, and when they tested the line afterwards it registered 'all the greens' on the test programme.

After that I had always assumed that it was as good as it would get - tested broadband speeds have since always been in the range 4-6 Mbps, and I had thought that 75% of 8 Mbps (allowing for overhead etc) was not bad, but that Obit were perhaps throttling it a bit sometimes!

Should be getting full 8 Meg now and if you were you'd get 18 Meg on ADSL2+

But you're not, so you won't

Might be worthwhile to ask your ISP to reset your profile (reset your target SNR margin) to 6dB. Depending on your ISP they may or may not understand what you mean. Mind you if you move to LLU the current profile will be irrelevant so need to bother.

I doubt that

more like 16 as the alt jumps when you switch to ADSL2+

You're right! I forget, unusually, to take into account a 3 dB increase in attn.

I revise my estimate to 16 - 17 Meg.

With a Billion 7800N router, you can tweak the SNR to get an even higher sync speed.

I was on up to 3.3MB with Zen Internet on ADSL Max but am now on up to 5.5MB with Vivaciti on LLU (ADSL2+).

My stats are currently:

Upstream 1020
Downstream 6261
SNR Margin(Upstream) 6.5
SNR Margin(Downstream) 0.6
Line Attenuation(Upstream) 25.2
Line Attenuation(Downstream) 48.0

In reply to a post by paul_liverpoolfc:

With a Billion 7800N router, you can tweak the SNR to get an even higher sync speed.

I know! At least for my Netgear DG834GT, if not for the Billion. Anyone can with the right router on any ISP.

But what relevance to the OP's query?

Sorry - was just letting the OP know that if he's not happy with the speed he does get, he may be able to improve it.

But I can see I was a fraction off-topic there.