[rtcweb] The meaning of SDP_PRANSWER

"Henry Lum" <Henry.Lum@genesyslab.com> Mon, 16 April 2012 15:52 UTC

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Date: Mon, 16 Apr 2012 08:52:56 -0700
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Thread-Topic: The meaning of SDP_PRANSWER
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From: "Henry Lum" <Henry.Lum@genesyslab.com>
To: <rtcweb@ietf.org>
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Subject: [rtcweb] The meaning of SDP_PRANSWER
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It's unclear to me what the purpose of SDP_PRANSWER is really for and
why it needs to be there. Originally I thought it was meant for early
media, but section 6.1.4 paragraph 3 says that it should not result in
starting of media transmission. Is there a reason to provide an answer
before media is ready to be transmitted? There are separate handles for
processing ICE candidates so I don't see a need to have provisional


I am not proposing PRANSWER for handling early media though, since I
believe early media is more of an application level issue (it's more
like late-billing on the application side) and should be considered as a
separate offer/answer if needed.