Re: [MMUSIC] AD Evaluation of draft-ietf-mmusic-rfc4566bis-32: Media Description

Ben Campbell <ben@nostrum.com> Mon, 18 February 2019 21:13 UTC

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From: Ben Campbell <ben@nostrum.com>
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Date: Mon, 18 Feb 2019 15:13:32 -0600
In-Reply-To: <355f8125-87f8-6372-8289-126fa126ccb9@alum.mit.edu>
Cc: draft-ietf-mmusic-rfc4566bis.all@ietf.org, mmusic WG <mmusic@ietf.org>, Colin Perkins <csp@csperkins.org>, Magnus Westerlund <magnus.westerlund@ericsson.com>
To: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Subject: Re: [MMUSIC] AD Evaluation of draft-ietf-mmusic-rfc4566bis-32: Media Description
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> On Feb 18, 2019, at 2:23 PM, Paul Kyzivat <pkyzivat@alum.mit.edu> wrote:
> 
> 
> 
>> On 2/11/19 10:45 PM, Ben Campbell wrote:
> 
>>> §2, “Media Description”: While true, the text here is not a definition of anything but syntax. Please add a sentence or two to say what the media description semantically represents.
> I'm having trouble finding a suitable semantic definition of Media Description.
> 
> My first thought is that it provides the information necessary to establish a media session. But while *Multimedia Session* is described, media Session isn't defined in the document.
> 
> I looked at RFC7656 (Taxonomy) for a definition, but it doesn't have one either. It defines RTP Session, and Multimedia Session as one or more RTP Sessions. That is close, but in SDP media sessions need not be RTP.
> 
> Is there any suitable existing definition???
> 
> If not, then how about:
> 
> "A Media Description contains the information needed for one party to establish an application layer network protocol connection to another party." ???
> 
> OR
> 
> "A Media Description contains the information needed for one party to establish a Media Session with another party."
> 
> "A Media Session is an application layer network protocol connection between two parties."
> 
> It seems important to get this right! It is essentially a broadening of RFC7656 beyond RTP.

I am okay with either of those. :-)

Ben.