[rtcweb] Lower-overhead protocol variations

Randell Jesup <randell-ietf@jesup.org> Wed, 20 February 2013 21:33 UTC

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Date: Wed, 20 Feb 2013 16:31:15 -0500
From: Randell Jesup <randell-ietf@jesup.org>
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Subject: [rtcweb] Lower-overhead protocol variations
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This is a relevant thread to current discussions:

http://www.w3.org/mid/D1737092-F63D-4821-B3FA-D425267E4F23@cisco.com

and continued with subject change in

http://www.w3.org/mid/4F4D6315.9000601@jesup.org

I'm re-evaluating if the original decision against even/odd was required,
in order to see if we can collapse the current draft 0-RTT proposal
into a single declarative "open" message on a stream with no response or ack
required. Even/odd (perhaps based on a property of the SCTP association?)
would avoid the need for mismatched channel pairs, and thus avoid the need
for the response/ack and the need to send with the in-order bit.

The only hole I've seen so far is that if the return stream isn't
currently within the range of valid streams (i.e. at the far end) there's
no easy way to return an error.  However, we expect to be able to
negotiate additional streams on request, so this may not really matter.

We may need to reserve more initial streams, but the overhead for this is
minimal.

Perhaps this would address some of the concerns voiced here.  Also,
someone will be posting a use case soon this sort of change will
help.... <jesup waits for the post>

-- 
Randell Jesup
randell-ietf@jesup.org