Re: [MMUSIC] Simulcast worries: Fallback in the a=rid language

Harald Alvestrand <harald@alvestrand.no> Thu, 22 October 2015 18:13 UTC

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To: Adam Roach <adam@nostrum.com>, Martin Thomson <martin.thomson@gmail.com>, Peter Thatcher <pthatcher@google.com>
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From: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [MMUSIC] Simulcast worries: Fallback in the a=rid language
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Den 22. okt. 2015 16:43, skrev Adam Roach:
> On 10/22/15 00:37, Harald Alvestrand wrote:
>> If I tell someone I can't take more than X from them (recv), it's
>> dangerous if they ignore it, because they can overrun my limitations
>> through ignorance.
> 
> And if they don't support the simulcast mechanism at all, they'll do the
> same thing. You're asking us to solve a problem that is unrelated to the
> mechanism.

I don't understand this comment.

If that (telling the other guy not to send more in a simulcast than you
want to handle) isn't the problem the mechanism was supposed to solve,
what IS the point of the mechanism?

I'm assuming that the correspondent that doesn't understand simulcast is
restricted by other attributes like a=imageattr (well, sort of), a=fmtp
and b=, so that this is regarded as a problem this mechanism doesn't
have to solve.


> 
>> That tells me that:
>>
>> ...
>> b) sendrecv is a bad idea
> 
> That has been well-established as the emerging consensus. If you find
> the string "sendrecv" in either draft-ietf-mmusic-sdp-simulcast-03 or
> draft-pthatcher-mmusic-rid-02 in a context other than "a=sendrecv",
> please point it out. My search turned none up.

Good. It was in simulcast-02; happy to see it gone.

> 
> /a