[tcpm] Updating Proportional Rate Reduction RFC6937 to PS

[Matt Mathis <[e-mail]>]

Following a discussion with the tcpm chairs, the authors of RFC6937 plan to
introduce a .bis document to update PRR from Experimental to Proposed
Standard.   PRR is supported in one form or another in 3 major operating
systems and has come to be very widely deployed over the last several years.

There have been no changes to the base algorithms for PRR-CRB (Conservative
Rate Bound) and PRR-SSRB (Slow Start Rate Bound).  However PRR can be
substantially improved by using a heuristic to dynamically switch
between algorithms, depending on the presence of additional losses.    We
plan to present a candidate heuristic, however there has not been any deep
studies of alternatives.  This approach was first described in section 5.2.
of Flach et al "An Internet-Wide Analysis of Traffic Policing"
<https://dl.acm.org/doi/abs/10.1145/2934872.2934873> and has already been
upstream for several years.

I could use some editorial advice:  RFC 6937 is too long and much too
"tutorial" in tone.   Does it work for RFC 6937.bis to state the
algorithms in normative language, but to have non-normative references
to RFC 6937 for context and background?  Can somebody point me to a pair of
existing RFC's that use this approach?   How much explanation should remain
in RFC 6937.bis?

We are aiming to have something ready for the next tcpm meeting.

Thanks,
--MM--
The best way to predict the future is to create it.  - Alan Kay

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