Re: [MMUSIC] SDPNEG: How to disable DCEP

Paul Kyzivat <pkyzivat@alum.mit.edu> Wed, 24 April 2019 22:25 UTC

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From: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Date: Wed, 24 Apr 2019 18:25:02 -0400
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Subject: Re: [MMUSIC] SDPNEG: How to disable DCEP
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On 4/24/19 4:37 AM, Christer Holmberg wrote:
> Hi,
> 
> I had an off-line discussion with Bo regarding how to know whether to 
> use SDPNEG or DCEP for a Data Channel.
> 
> Section 5 says:
> 
>     ”This section defines two new SDP media-level attributes that can be
> 
>     used together with the SDP Offer/Answer mechanism to negotiate data
> 
>     channel-specific and subprotocol-specific parameters without the
> 
>     usage of DCEP [I-D.ietf-rtcweb-data-protocol].”
> 
> Do we consider this clear enough that the presence of those attributes 
> (well, only dcmap, since dcsa is optional) will “disable” usage of DCEP, 
> or do we want to be more clear?

The distribution of specs across multiple documents makes it really 
fuzzy what is normative for what.

Perhaps something should be said about the validity of using a 
webrtc-datachannel media stream for establishing data channels via SDP 
with dcmap and/or DCEP. I don't think this is said anywhere else.

	Thanks,
	Paul