Re: [MMUSIC] draft-ietf-mmusic-sctp-sdp-07 SCTP SDP syntax question

Paul Kyzivat <> Thu, 02 October 2014 18:55 UTC

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Date: Thu, 02 Oct 2014 14:55:38 -0400
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Subject: Re: [MMUSIC] draft-ietf-mmusic-sctp-sdp-07 SCTP SDP syntax question
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On 10/2/14 2:31 PM, Christer Holmberg wrote:
> Hi,
>>> Keep in mind that the purpose of draft-ejzak-mmusic-data-channel-sdpneg is NOT to negotiate
>>> the usage of the SCTP association.
>>> It is assumed that the usage of the SCTP association is data channel, and the draft defines a
>>> mechanism to negotiate data channels on that SCTP association.
>> The purpose is to negotiate the use of channels, which is almost the same as negotiating the use of > individual SCTP streams within an SCTP association.
> Correct. But, it is not used to negotiate the SCTP association usage, which I think is what Christian has been talking about. It assumes that the SCTP association is used for data channels.

Yes. But for the most part Christian is talking about stream/channel 
usages that have not yet been defined. When the are defined, they could 
be done so using channels or something else. The main constraint here is 
enabling this stuff to work with webrtc.

I think that constraint is effectively forcing the use of the data 
channel association usage.

And this is all hypothetical because draft-ejak is far from complete. 
So, if it goes forward at all it may end up different from what it is now.