Re: [AVT] The need for Offer/Answer sections in RTP payload format specifications

"John Lazzaro" <lazzaro@eecs.berkeley.edu> Tue, 27 January 2004 19:34 UTC

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To: avt@ietf.org
From: John Lazzaro <lazzaro@eecs.berkeley.edu>
Subject: Re: [AVT] The need for Offer/Answer sections in RTP payload format specifications
Date: Tue, 27 Jan 2004 11:27:06 -0800
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> Magnus Westerlund <magnus.westerlund@ericsson.com> writes:
>
> Thus we request that authors write an "Offer-Answer model 
> consideration"
> in their SDP usage section. This should cover the following:
>
> - How configurations effect the interoperability.
> - What parameters that are possible to subset and which are not.
> - Recommendations on how to achieve good interoperability.

In regards to RTP MIDI, I think it may be better for the readers
of the "candidate Last Call" document to judge if the SDP
sections as written (pages 20-24, and pages 68-103) handle
Offer/Answer OK, and if the best solution is a new separate
Offer/Answer section or a rewrite of the existing structure to
discuss Offer/Answer in more depth.  This way, I can handle
those criticisms along with all of the other Last Call feedback
at one time, in the hopes of reducing the total number of
rewrite cycles before "candidate Last Call" becomes "Last Call".

The alternative (going off and doing -02.txt versions to become
the new "candidate Last Call", with a separate Offer/Answer section)
probably knocks a month off the schedule.  Not good ...

My own intuition is that the RTP MIDI document is OK as it
stands in regard to interop -- the world of RTP MIDI applications
is big, and interoperability is going to require a framework
document for each class of applications, written by application
experts.  The purpose of the SDP section in the payload document
is to define a common set of SDP tools that these frameworks
can subset.

---
John Lazzaro
http://www.cs.berkeley.edu/~lazzaro
lazzaro [at] cs [dot] berkeley [dot] edu
---


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