[ippm] Re: New Version Notification for draft-whimir-ippm-stamp-cos-ecn-00.txt

[Gorry Fairhurst <[e-mail]>]

I think this could be a useful draft, and it is good to see support 
for measurements on the return path.

One thing that I really think this I-D ought to address is that if the 
tests generate an appreciable load (which seems likely to be important 
to measure congestion marking), then the flow that advertises an 
ECN-Capable Transport, actually needs to follow the rules for flows that 
are marked in this way.

This means the flow needs to detect and reflect any CE-marking (which I 
think this spec does).

It also could mean that a tester ought to detect (and ignore) CE marks 
when ECT is not set; but more importantly when the flow is marked as 
ECT(?), I think the source now must REACT to reflected CE-marks to 
reduce the load it generates, this could be a full ECN alagorithm, or 
perhaps could be a simplified load control which might make the 
measurement easier to interpret. I'd be interested to understand how 
this could be realised, and see more.

Gorry