Re: [rtcweb] Another reason not to use SDP (was: Draft agenda for IETF 87)

Martin Thomson <martin.thomson@gmail.com> Fri, 12 July 2013 18:29 UTC

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Date: Fri, 12 Jul 2013 11:28:41 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Peter Thatcher <pthatcher@google.com>
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Cc: "Cullen Jennings \(fluffy\)" <fluffy@cisco.com>, "<rtcweb@ietf.org>" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Another reason not to use SDP (was: Draft agenda for IETF 87)
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On 12 July 2013 11:21, Peter Thatcher <pthatcher@google.com> wrote:
> If we write it down with such detailed instructions, is a browser banned
> from accepting more than the explicitly allowed SDP in calls to
> setLocalDescription and setRemoteDescription?  For example, what if lots of
> web apps get SDP from a particularly popular gateway device that adds a
> particular SDP attribute, and if the browser "listens" to that SDP
> attribute, things work better (for example, it might be a bandwidth-related
> attribute).  Can the browser "listen" to that SDP attribute even though it
> isn't explicitly supported by the WG?  Or does it have to wait for it to be
> added to the explicit instructions?

That depends entirely on the nature of the instructions.  Allowing for
extensibility is always really, really hard, but maybe there is enough
experience with SDP now that this sort of scenario could be supported.