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

Bernard Aboba <> Thu, 20 June 2013 17:49 UTC

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From: Bernard Aboba <>
To: Peter Thatcher <>, Robin Raymond <>
Date: Thu, 20 Jun 2013 10:48:55 -0700
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Subject: Re: [rtcweb] WebRTC JS object API with SDP shim option
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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.