Subject: [Sip] Question on Unify draft

From: "Chen, Xin (Xin)" <[email-masked]>
Date: Tue, 26 Feb 2002 11:24:56 -0000

In this draft, in figure 4 (solution for One-of-N Codecs problem), it uses
the a=inactive in the first offer to stop the callee to send media. But is
it possible that the callee answers the offer by changing the a=inactive to
a=active and starts to send media immediately?

If this is possible, then this solution won't work, am I right?

Xin Chen

Lucent Technologies
Tel: +44 1793 883137
Mobile: +44 7799 034668

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From: Gonzalo Camarillo <[email-masked]>
Date: Tue, 26 Feb 2002 18:21:24 +0200

Hello,

> If this is possible, then this solution won't work, am I right?

The direction attribute cannot be change in the answer. It has to be the
same as in the offer. See:
http://www.ietf.org/internet-drafts/draft-ietf-mmusic-sdp-offer-answer-01.txt

Regards,

Gonzalo

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From: Jonathan Rosenberg <[email-masked]>
Date: Wed, 27 Feb 2002 02:38:43 -0500

> http://www.ietf.org/internet-drafts/draft-ietf-mmusic-sdp-offer-answer-01.txt

Well, it can change it, but in this specific case, it cannot. If can
basically be "downgraded", but not "upgraded" in the answer. Since
inactive is the lowest "grade", it cannot be downgraded further and thus
cannot change.

-Jonathan R.

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