Re: [rtcweb] ALPN question - other labels?

Martin Thomson <martin.thomson@gmail.com> Fri, 08 August 2014 02:41 UTC

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Date: Thu, 07 Aug 2014 19:41:43 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Subject: Re: [rtcweb] ALPN question - other labels?
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On Aug 7, 2014 7:25 PM, "Paul Kyzivat" <pkyzivat@alum.mit.edu> wrote:
> My primary question is how is a browser expected to behave if some other
label is offered? Will it still support use of the JSEP APIs?

ALPN requires that a peer in the server role reject the connection if it
can't select a protocol. That is what Firefox will do, though it will
tolerate no ALPN extension as long as it doesn't have confidential media.

> And, for interop reasons, will there be a way to get a browser to offer
another label and still support the JSEP APIs if the other end accepts it?

That is an interesting question. You would need to teach the browser that
other protocol, I guess.