Subject: [Tsvwg] draft-briscoe-tsvwg-re-ecn-tcp-03.txt

From: Sally Floyd <[email-masked]>
Date: Tue, 7 Nov 2006 14:37:38 -0800

Bob -

I just read Appendix I of the re-ecn draft, on "Argument for holding 
back the ECN nonce",
and it seems pretty fair to me.

I have a question about the case of congestion on the access link to 
the receiver.
(E.g., the ethernet in the campus dorm, going to a student's dorm room).
Can re-ecn detect cheating when a packet is dropped or marked on the
last link to the receiver?  This would seem an important use case to me.
Of concern to the campus web server sending data to the student's dorm 
room.

I personally would state the case of the sender wanting to protect 
against receiver cheating
not as "the sending transport choosing to act in the interests of the 
congested router",
but as the sender (e.g., the large web server) having some incentive to 
do its own small
bit to help protect the Internet from congestion collapse.  That is, I 
think this could be in the
sender's interest as well as in anybody else's interest, particularly 
when the sender is a large
web server.

And I personally would see the case of "the sending transport wanting 
to allocate its own
resources in proportion to the rates that each network path can 
sustain", as instead the
sender not wanting to spend a lot of work on a flow if many of the 
packets are just going to be dropped downstream...

- Sally
http://www.icir.org/floyd/