Sorry if you find it difficult to understand
I understand everything you wrote (in the post I'm replying to).
What I didn't originally understand was the "it" that represents the consequences of the link being unplugged, and the counters sent back. But I guess you are talking about DLM making an intervention.
send these errors back [...] to the DLM and see that it had a rather long period where it couldn't communicate with the modem
I can't tell you for sure what DLM makes use of to choose when to intervene, but I can be pretty sure that it *isn't* the UAS value.
If you just leave the modem disconnected from the phone line, but powered up, the UAS counter will be constantly increasing. Why should that circumstance be a thing that DLM cares about? DLM can only intervene by defining the end result of the sync - it can't do anything to make a sync happen, and certainly can't make any change whatsoever if there is no physical path.
To me, it just doesn't make sense to have DLM intervene because of a physical disconnection.
this will create UAS/SES errors and the modem will record them
SES could be a factor in the decision-making, but SES shouldn't be incrementing in the circumstances you describe. When the UAS counter is active, SES should be inhibited anyway... not least because the modem can't be performing CRC checks on a line that isn't in sync.
And remember that UAS, SES and ES aren't "errors" as such. They are "seconds" during which certain events or states were seen.
but whether it will report the SES/UAS back to the DLM is another matter all together
The specification for what gets sent back is included in spec G.997.1, where all the parameters that get sent from modem back to the DSLAM tend to be named something-XFE (for example, UAS-LFE, ES-LFE, SES-LFE, CRC-PFE).
DLM then gets the values from the DSLAM.
Interestingly, the BT SIN that regulates the VDSL2 modems has a definition for the minimum parameters that must be correctly sent back to the [email protected]
Take a look at the SIN document
, requirement "R.VDSL2.17
The SIN includes FECS-LFE, ES-LFE, SES-LFE, so you can probably assume that these could well be used by DLM. However, it doesn't include UAS-LFE or CRC-PFE
- so these almost certainly aren't included in the DLM calculation!
That last one is a surprise to me, certainly!