You are, of course, referring to a VDSL2 circuit between the FTTC and your CPE as part of the Openreach GEA product. In this case, it is known that the flow of statistics is as follows:
No I am plain old adsl 'max' IPStream.
I guess it comes down to how the router updates the DSLAM. My reasoning was that if these updates are event-driven, such that the DSLAM is notified in real time for each error, my efforts would be doomed to pointless. But if DSLAM periodically polls the router, and if I can reset the stats at a rate much faster than it is being polled then, most of the time the values perceived by DLM would be vastly reduced.
BUT I have thought of a drawback, and am getting cold feet.
Suppose my exploit worked as planned, DLM would then calculate (for example) the HEC count over a given period by subtracting the previously reported value from the current value. And if I have rest the stats in the interim then the current value is less than the old value, DLM will end up with a negative number.
Now imagine the credible proposition that the DLM code-path has never been tested for negative numbers and that it fails to handle signed arithmetic propery. It could then conclude from that small negative number that (assuming 32 bit arithmetic) the best part of 4 billion HECs had occured.
The reason I am willing to consider the above is that, actually, it would fit in with the fact DLM raised my margin after I spent a day playing with a new router. It may be the fact I reset the connection a few times but I'm unconvinced as I was very careful, restricting myself to no more than one reset an hour, I learned that the hard way.
But I did manually reset the errors stats several times. Could that (by above reasoning) explain why I got 'hit' by DLM in the first place?