Attainable rate and actual rate

[#1]

Last month I had a problem with my BB which was fixed fairly quickly but the download speed was reduced from around 8.6Mbps to around 6Mbps. I've waited the obligatory 10 days to see if it went up again, but nothing has happened.

I have checked the router stats and it confirms that the attainable IS 8.6Mbps. Can someone here explain, in layman's terms, why I have lost about 2.5Mbps? It's quite a big drop. I want it back to what it was!

I have attached a screenshot of my stats if that helps.

Thanks

[#2]

Those stats report that the attainable SYNCH rate is 8.4, the actual rate being just over 8.

The actual synch rate is determined at the time of synch and does not change. The attainable rate is dynamic and changes according to the ambient noise margin. In the case of the stats shown, the noise margin is now higher than it was at synch time, so in theory the line could run a little faster than it is presently doing.

Those stats might imply that the last synch was after dusk and now during daylight the noise margin is better. A router restart during the middle of the day might deliver a small improvement.

There is always going to be a difference between SYNCH rate and usable DATA rate as reported by speed testers.

One thing that does need checking is the PlusNET profile for the line ... which is now not easy for users to find and I do not have the link to hand.

You might care to go run the BT line speed test - further test option which will give you full details of the line's profile.

You might see some minor improvement if the US target SNRM can be adjusted to 6dB - that though is a decision for PlusNET bas d on the line's reported error
Rates.

HTH?

[#3 · Accepted solution]

Your current profile on our suppliers system is "WBC 160K - 24M No delay (INP 0) 6dB Downstream, UC No delay (INP 0) 6dB Upstream (ADSL2+)" so there's no adjustments we can make at this moment in time that would bring your speeds up.

I've fully tested your line which will have caused your connection to drop but it hasn't improved the speeds unfortunately.

[#4]

@MatthewWheeler,

Is the error rate on this line low enough to consider a DS 3dB TARGET SNRM?

[#5]

@Townman The errors on the line aren't too high but a 3db target could push them up and then DLM would increase it back to 6db.