Re: [MMUSIC] Do we really need TCP/DTLS/SCTP proto field?

Christer Holmberg <> Thu, 16 February 2017 16:56 UTC

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From: Christer Holmberg <>
To: Ben Campbell <>, Eric Rescorla <>
Thread-Topic: [MMUSIC] Do we really need TCP/DTLS/SCTP proto field?
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Date: Thu, 16 Feb 2017 16:55:53 +0000
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Subject: Re: [MMUSIC] Do we really need TCP/DTLS/SCTP proto field?
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My suggestion is to keep the TCP/DTLS/SCTP definition.

We earlier made a choice to restrict the scope of the document (by removing plain SCTP and DTLS-over-SCTP proto values), and I think we should keep the current scope.



From: mmusic [] On Behalf Of Ben Campbell
Sent: 16 February 2017 17:52
To: Eric Rescorla <>
Cc: mmusic WG <>
Subject: Re: [MMUSIC] Do we really need TCP/DTLS/SCTP proto field?

Process background: draft-ietf-mmusic-sctp-sdp was on today's IESG telechat. The draft is approved for publication, but with a point raised to ask the WG resolve Ekr's question.



On 16 Feb 2017, at 9:43, Eric Rescorla wrote:
I raised this with the authors, but maybe it is worth asking the mailing list.

It seems like we are trending towards a world where we just ignore the transport
component of the proto field and let ICE work things out. In that vein, I wonder
do we really need to register/define TCP/DTLS/SCTP. It's only really useful if
we think people will do SCTP over DTLS with TCP without ICE. Is that actually
likely. I note that per previous discussions, JSEP already requires that you use
UDP/DTLS/SCTP all the time: