Re: [bfcpbis] [MMUSIC] m= line protocol in case of ICE

"Charles Eckel (eckelcu)" <> Thu, 01 December 2016 20:32 UTC

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From: "Charles Eckel (eckelcu)" <>
To: Roman Shpount <>
Thread-Topic: [bfcpbis] [MMUSIC] m= line protocol in case of ICE
Date: Thu, 1 Dec 2016 20:17:13 +0000
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Cc: "" <>, "" <>, Christer Holmberg <>, "" <>, Alan Ford <>
Subject: Re: [bfcpbis] [MMUSIC] m= line protocol in case of ICE
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Why would selecting TCP/BFCP as transport violate RFC 6544? Perhaps it does, but after a quick scan I am not sure why.


From: Roman Shpount <>
Date: Tuesday, November 29, 2016 at 10:38 AM
To: Charles Eckel <>
Cc: Alan Ford <>om>, "" <>rg>, "" <>rg>, "" <>rg>, Christer Holmberg <>
Subject: Re: [bfcpbis] [MMUSIC] m= line protocol in case of ICE

On Tue, Nov 29, 2016 at 12:48 PM, Charles Eckel (eckelcu) <<>> wrote:
It seems to me that the most straightforward approach would be to mandate support for BFCP over UDP when using ICE, use UDP as the default candidate, and signal the BFCP m-line as if it is BFCP over UDP. If we can mandate the use of DTLS, that would be even better.

I agree.

The only issue that I still have, if DTLS is not used, what protocol is used when ICE tcp candidate is selected for transport. Is this TCP/BFCP (which goes against RFC6544)  or is it UDP/BFCP with RFC4571 framing? If it is UDP/BFCP with RFC4571 framing, what transport tag should be used in the re-INVITE which is sent after ICE nomination with only selected candidate? Should it be TCP/UDP/BFCP or something similar?

Roman Shpount