Re: [MMUSIC] Issue #27: Allow RTP attributes in non-media m= sections

Christer Holmberg <> Thu, 16 February 2017 17:07 UTC

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From: Christer Holmberg <>
To: Eric Rescorla <>, mmusic WG <>
Thread-Topic: [MMUSIC] Issue #27: Allow RTP attributes in non-media m= sections
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Date: Thu, 16 Feb 2017 17:07:19 +0000
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Subject: Re: [MMUSIC] Issue #27: Allow RTP attributes in non-media m= sections
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>The basic issue is that it's possible to have a situation where you have both
>media and data m= sections but the BUNDLE tag is associated with the data
>m= section and now you need to put the TRANSPORT and IDENTICAL
>attributes somewhere. The JSEP editors discussed this and came to the
>conclusion that it should go with the BUNDLE tag (i.e., in the data m= section)
>and that BUNDLE should forbid this, but it requires a change to BUNDLE.

Did you mean to say that BUNDLE should NOT forbid this?

Based on your GitHub discussion, my understanding is that you want to allow to include RTP-specific parameters (‘rtcp-mux’, ‘rtcp’, ‘rtcp-mux-only’ attributes etc) in the data m= section.

To repeat what I said on GitHub:

This has been discussed in the past, and the outcome has been to now allow RTP-specific parameters in non-RTP m= sections.

A solution would be to simply change the bundle tag when the RTP m= sections are added.

…OR, we change the mux category for the RTP-specific parameters. But, that of course means they have to be added to every RTP m= section.