Re: [rtcweb] Isolating data channels (Re: Asking TLS for help with media isolation)

Martin Thomson <martin.thomson@gmail.com> Mon, 07 April 2014 17:23 UTC

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Date: Mon, 7 Apr 2014 10:23:05 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [rtcweb] Isolating data channels (Re: Asking TLS for help with media isolation)
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On 7 April 2014 10:20, Harald Alvestrand <harald@alvestrand.no> wrote:
> I was actually thinking "protocol" as in the string that goes into the
> datachannel setup packets. PPIDs would work too for separating
> browser-to-brower from app-to-app, but I wasn't thinking of them.

That would require carving out a space to use right now.  That
impinges to much on application autonomy for my liking.

> Yes, data channels do cost something to set up. But we're already paying the
> DTLS tax in order to set up the keying, so it's "just" another
> request/response. How many extra round trips does the SCTP setup add?

2.

> (and to Matthew: At least we wouldn't have *yet* another congestion context to
> manage, which would be the case with a separate TCP connection. There are
> always tradeoffs.)

I'm certain that Matthew wasn't talking about TCP.