Re: [rtcweb] WebRTC JS object API with SDP shim option

Robin Raymond <> Thu, 20 June 2013 17:52 UTC

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Date: Thu, 20 Jun 2013 13:52:38 -0400
From: Robin Raymond <>
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Subject: Re: [rtcweb] WebRTC JS object API with SDP shim option
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Would someone produce unit tests against the produced SDP and offered 
SDP that is the "defined webrtc spec" so the bar could be set? Hitting a 
moving target will be challenging. Seems to me a lot of what is SDP is 
not extremely well defined at this point so the only thing I can do is 
produce "good" SDP since the exact definition of what is webRTC SDP 
seems a bit lacking.


> Bernard Aboba <>
> 20 June, 2013 1:48 PM
> Peter Thatcher said:
> "How are you going to test that shim without a working implementation 
> of the clean API?
> One thing you could do is build a shim of clean API -> SDP.  Then, 
> you'd have two shims which would make a fun combination (SDP -> clean 
> API -> SDP) and you're prove that SDP munging and the clean API are 
> equivalent in power.
> Or you could fork Chrome or Firefox.
> Either way, you have a lot of work ahead of you.  Best of luck."
> [BA] Getting a working implementation of a clean API is not the 
> biggest issue.  The biggest issue is how to determine whether a shim 
> is "successful" or not. At this point, the reality is that the 
>  implementation code (including undocumented behavior) represents the 
> WebRTC 1.0 specification, rather than the documents produced by W3C 
> and IETF.  This makes the bar (either "backward compatibility" or 
> "equivalent in power") difficult to define, let alone satisfy.