PPP LCP Send Termination Request [User request]

[#1]

Since I upgraded from Fibre to Fibre Extra, my previously solid connection has started dropping occasionally. The connection returns after 1-2 minutes. The Plusnet Hub One log shows the following:

17:42:59, 28 Aug.	(727257.500000) PTM over DSL is down after 554 minutes uptime
17:42:59, 28 Aug.	(727257.500000) PPPoE is down after 552 minutes uptime [Waiting for Underlying Connection (WAN Ethernet 7 -​ Down)]
17:42:56, 28 Aug.	(727254.880000) PPP LCP Send Termination Request [User request]

I wonder why the downstream data rate is higher than the maximum data rate?

6. Data rate:	19978 / 79903
7. Maximum data rate:	29270 / 67565
8. Noise margin:	11.0 / 3.2
9. Line attenuation:	20.1 / 16.7
10. Signal attenuation:	19.9 / 16.7

 Any help is much appreciated.

[#2]

I get similar occasional disconnections. I think it is down to the DLM trying to optimise the line and get the maximum possible out of the link. It seems to be doing well!!

The maximum data rate (I think) is calculated by the modem on the basis of a 6.0dB SNR. Openreach have allowed SNR to drop to a minimum of 3.0, so your line is running at 3.2 giving you a 79903 sync rate. At a theoretical 6.0 SNR you should expect a 67565 data rate. 

So DLM is doing OK.

[#3]

The maximum attainable data rate is calculated using whatever the target SNRM is set at.

In this case, it would probably make sense if the target SNRM is still 6 (or something higher than 3), and the lower current SNRM and maximum attainable rate is due to there being more noise present than when the connection was established.