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[Helpneedadvice]

>> 1458 (was previously blank)

Ah thanks - RWIN of 204192 is for lines syncing at full 8Mb, since youre getting more like 6Mb speeds then 153144 should work well too.

>> Meaning - I think one of these settings has helped but not sure which one!

If its now working much better - which it seems to be - as there's quite an improvement..  then leave alone 

Hi Kitz

I'm syncing at between 7500-8000 kbps consistently, but throughput is around 6M (limited by current profile 6500)- should that RWIN value be set for the sync or the throughput value?

Just did another download speed test 780 kBps - not bad for Fri 5pm. Got similar all day. I'm wondering if they've completed the fix at the exchange too!

Thanks for all your help Kitz and Eric - I'm a happy bunny now!

[kitz]

>> but throughput is around 6M (limited by current profile 6500)- should that RWIN value be set for the sync or the throughput value

Its said to be sync -  its my own preference to set for average throughput speed, and what Ive found works for me.  My theory is that if you dont always get the higher speed then just take it down a notch.  The lower figure I recommended gives an allowance for that fact.

>> ust did another download speed test 780 kBps - not bad for Fri 5pm.

Indeed - those speeds are much better and what you'd expect to see around this time of the evening. 
There will always be some sort of contention during the evenings 6.25 Mbps is a fair figure and considered acceptable

[Helpneedadvice]

Hi folks, i'm back.

I have a couple of questions...

My ISP have agreed to ask BT to have me reprofiled. It was supposed to have started over a week ago. However, when BT last did that, the SNRM on my router stats started off at 6dB and only grew to 12-15dB over the next few days because at the time I was getting lots of loss of syncs.

• I have not had loss of sync at all in the last 5 days since the reprofile was supposedly instigated, yet there seems to have been no reset of target SNR at the exchange by BT as part of the initiation process. It has remained at 12-15dB all along. I would have expected it to start out again at 6dB like last time and I have been watching it closely. Does this suggest BT haven't started the reprofiling properly? There has been no reason for it to rise above 6dB as i haven't had any disconnects/ losses of sync.
  (I got my first loss of sync this morning since the supposed reprofile 5 days ago. When it reconnected, I got 12dB SNRM on my router immediately on reconnection)
• When i got the loss of sync today, my usually consistent downstream attenuation went from 33dB to 32dB. I thought this was a stable figure and didn't change? Have BT been playing with my line, I'm wondering?

[roseway]

What speed are you connecting at now? Looking at the speeds you mentioned a couple of messages ago, it may be the case that you are now connecting at the maximum speed with some noise margin to spare, which would be an excellent result.

A small change in the reported attenuation has no significance. The reported figure is a sort of average of the attenuation of the different frequencies being used, and these have probably changed a bit now with the improved conditions.

[Helpneedadvice]

Hi Eric

Well I have been getting 7M+ consistently just recently (profile still 6.5M), but this morning i had my frst loss of sync for 5 days. I reconnected at 6.3M. I noticed it about three hours later and diconnected and got my 7M+ sync back. However, I then did a BT speedtest for throughput (profile now down to 5.5M cos of the blip) and the test failed and asked for a second test (which I can never get to work). I then downloaded a large file to look at the transfer rate. I was only getting 60kBps so around 480kbps. Something strange is happening today!

I would be happy with the 12dB target SNRif i was syncing at the max, but I am not. I do occassionally get 8.014M, but 5 days ago i resynced at 7.4M and I just left it there to see what happened as I am supposed to be being reprofiled at the moment. I just think I may get the 8M more often if they reset the target SNR.

Even with that theory you mention, would I not have seen an initial 6dB SNRM when reprofile first initiated as i did last time?

[Helpneedadvice]

Oh sorry - meant to say throughput has been pretty good recently pre-today. Whilst syncing at 7M+, was getting 5-6Mbps. Am wondering whether BT are carrying out VP work on my exchange today. It is still showing as Red on the exchange page.

[roseway]

>> Even with that theory you mention, would I not have seen an initial 6dB SNRM when reprofile first initiated as i did last time?

Not necessarily if you were connecting at the maximum speed. The target noise margin isn't a fixed value at sync time, it's simply the lowest value which will be allowed. If your line can connect at the maximum speed with a higher margin than the target, then it will do so.

However this is perhaps academic in your case. It does look as though BT have only lowered your taget noise margin by one notch, from 15 dB to 12 dB. Personally I think your best bet is to leave it as is for a couple of weeks and see how it goes. If your target margin were to be set right down to 6 dB you might very well find that your connection becomes unstable, resulting in the target margin getting bumped straight up again.