Re: [MMUSIC] RTSP 2.0 SDP issue: Directionality attribute

worley@ariadne.com (Dale R. Worley) Tue, 19 March 2013 19:37 UTC

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Date: Tue, 19 Mar 2013 15:37:14 -0400 (EDT)
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From: worley@ariadne.com (Dale R. Worley)
Sender: worley@ariadne.com (Dale R. Worley)
To: Magnus Westerlund <magnus.westerlund@ericsson.com>
In-reply-to: <514767D1.3000906@ericsson.com> (magnus.westerlund@ericsson.com)
References: <51425974.9070608@ericsson.com> <201303151431.r2FEVHJ9498642@shell01.TheWorld.com> <514767D1.3000906@ericsson.com>
Cc: mmusic@ietf.org
Subject: Re: [MMUSIC] RTSP 2.0 SDP issue: Directionality attribute
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> From: Magnus Westerlund <magnus.westerlund@ericsson.com>
> 
> I thus propose a more generic version of your text in the D. section:
> 
>    This appendix describes how an SDP file determines the operation of
>    an RTSP session.  Thus, it is worth pointing out that the
>    interpretation of the SDP is done in the context of the SDP receiver
>    is the one being configured.  This is the same as in SAP [RFC2974],
>    this differs from SDP Offer/Answer [RFC3264] where the SDP describes
>    what the peer agent is ready to receive and willing to send.

I agree with the overall concept, but there are some edits that would
help:

There's some flaw in the wording around "of the SDP receiver is the
one".  Perhaps it was intended to be "... of the SDP receiver, which
is the one being configured."?

Strictly, in "the same as in SAP [RFC2974],", the final "," should be
";", as the two things being joined are complete sentences.

The final clause does not seem definite enough to me, as "the peer
agent" is used rather than "the agent sending the SDP".  I suppose
that is the meaning that it must have, but in many situations, "the
peer agent" is used to denote the agent at the *other end* of the
connection from the agent being described.  So I would say "where the
SDP describes what the agent sending it is ready to receive and
willing to send."

Dale