Re: [rtcweb] revisiting MTI

Ted Hardie <> Mon, 15 December 2014 22:03 UTC

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Date: Mon, 15 Dec 2014 14:03:18 -0800
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From: Ted Hardie <>
To: Peter Saint-Andre - &yet <>
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Subject: Re: [rtcweb] revisiting MTI
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On Mon, Dec 15, 2014 at 1:37 PM, Peter Saint-Andre - &yet <>

> Not as far as I can see.
> Ten years ago if we'd had this discussion, H.261 might have been MTI. Ten
> years from now, H.264 will seem ancient, too.
> I fully expect that someone in the IETF (perhaps not us) will revisit the
> MTI decision once we have better alternatives.
> Peter

​The nice thing is that our current model allows us to have nice things
right away; as soon as they are in common, they may be selected by
negotiation.  What the MTI gives us is a way to avoid interoperability
failure.  So the key question isn't really "Is there something better?" but
"Is the current MTI so bad that folks aren't willing to use it, so we are
once again at risk of interoperability failure?".

Whenever we are at risk of interoperability failure, the IETF may have to
revisit the question.  But the future group will have an option we lack:
if nothing else seems more likely to be adopted, it can fall back on the
current MTI.  That may make the calculus a bit easier; we may also have
enough interoperability with some later codec that the answer will be
obvious.  I have no crystal ball, but I certainly hope we will not have to
go through this whole experience again.