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[jakk4]

Hi I have quite a long line to my exchange, maybe 2 miles ish. using any speed estimator when using my phone number/postcode, including BTs tool, they say the speed I should get would be 1 meg, 1 1/2 if I'm lucky. Exchange I am on is MRMID if that helps. I have recorded my line stats for the past few syncs, and here they are, as well as the sync rate they were recorded at;

1984k
LocalSNRMargin                                     = 16.0 dB
LocalLineAttn                                      = 53.0 dB

2240k
LocalSNRMargin                                     = 16.0 dB
LocalLineAttn                                      = 53.5 dB

2560k
LocalSNRMargin                                     = 17.0 dB
LocalLineAttn                                      = 54.0 dB

Now, I know most tools are only very rough when they are estimated based on line stats and current sync rate, but most I use suggest I should eb able to achieve ~5500kbps ? My router/modem is a Belkin F5D7632-4 which some say achieve low sync rates, and isn't the best for MaxDSL. But considering BT is wrong in say I can only achieve 1500 max due to ym current sync rate, is ~5000 possible considering the line stats and the fact that i am so far away from my exchange?

Thanks

[kitz]

Hi

looking from those stats (from what you say I assume they were taken shortly after sync up)..  then it looks like your line has a Target SNR of 15dB.
There must be some reason why the DLM has set your Target SNR at 15dB - probably due to periods of instability during the training phase?
- each time you switch your router on now - it is going to sync at the highest speed it can whilst still allowing an SNR Margin of 15dB.


If your Target SNR is 15dB then a sync speed of around 2500 may well be about maximum for your line.
How stable is your line right now? Do you get any disconnects?


-----

Your IP profile which is going to affect your actual achievable throughput speeds is going to be based on your lowest sync speed over the past 3 days. Therefore from what info you have given  -  throughput speed in the region of 1Mb - 1.5Mb is about right.

Have you tried to see if you can do anything to increase your SNR Margin* by carrying out the suggestions on my Low SNR page.
If you can increase your SNR Margin then you should sync at higher speeds.
If you need any further info or help on this please ask.


Finally if I were you - once you get a sync speed of over 2272 kbps I would keep my router plugged in for as long as possible without rebooting.

If you can keep the higher sync speed stable for 3 days - then your IP profile will be raised..  which should give you a throughput speed of 2Mb.  Any sync speed over 2272 kbps should move you up a notch and get you on the 2Mb actual speeds.

You wont get throughput speeds of 2.5Mb until you can get a stable sync of 2848 kbps and above.

* caution SNR Margin and Target SNR are related but not the same thing