Re: [rtcweb] Requesting "SDP or not SDP" debate to be re-opened

Iñaki Baz Castillo <> Thu, 20 June 2013 16:15 UTC

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From: Iñaki Baz Castillo <>
Date: Thu, 20 Jun 2013 18:15:13 +0200
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To: Harald Alvestrand <>
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Subject: Re: [rtcweb] Requesting "SDP or not SDP" debate to be re-opened
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2013/6/20 Harald Alvestrand <>:
> I think interoperability with an application written to the implementations
> that are based on the current specifications (that is - a Javascript
> application that you could load into both Chrome and your demo of CU-RTCWeb,
> using a JS shim in your demo, and have them talk to each other) would be a
> pretty compelling argument.

Hi Harald, with all due respect:

So, it seems that the current SDP-based spec is God, and if somebody
wants to propose another alternative, it must be compatible with God,
regardless that God is not yet a proven standard and what some of us
are asserting is that God is bad, very bad. Am I right?

IMHO it would be much more interesting a JS demo that takes the SDP
generated by Chrome and "converts" it into a Jingle XML session
description (I mean XEP-0167), and that can interoperate (via XMPP
over WebSocket or whatever) with a XMPP/Jingle endpoint by
incrementally sending/receiving transport (ICE stuff) and media
capabilities (as XEP-0167 allows) in different XMPP messages.

And it would also be interesting a JS demo that interoperates with a
SIP gateway and is able to perform the "hold" / "unhold" feature so
widely extended in SIP world (via reINVITE with a=inactive/sendonly
and 200 "OK" with a=inactive/recvonly).

It seems that we must prove how bad SDP is while the fact is that
those in favour of the SDP-based model should demonstrate how
"flexible" and powerful it is. As far as we can see in the spec
development, SDP does not seem to be so good and hence it should be
questionable IMHO.

Just my opinion.

Best regards.

Iñaki Baz Castillo