[tcpm] draft-kuehlewind-tcpm-ecn-fallback-01.txt

[John Leslie <[e-mail]>]

   I very much support this sort of work; but I think any RFC will have
to rely more on stated principles than an algorithm.

   This algorithm will fail badly if the actual path changes often
enough between ECN-friendly and ECN-unfriendly.

   Also note that we already know of several flavors of ECN-unfriendly.

   IMHO, we need to start using ECN early in the absence of indications
of an ECN-unfriendly path; and back off quickly in the presence of
such indications.

   There may (or may not) be other indications of path changes, which
we could use to be more fearful...

   But fundamentally, clearing ECN bits just puts us into packet-drop
as the only signal, while dropping ECN-aware packets may or may not
indicate any congestion. When a significant fraction of ECN-aware
packets get dropped, it's clearly time to stop ECN-marking.

   Et cetera...

--
John Leslie <[e-mail]>