Re: [rtcweb] Data Channel Negotiation and reopening of decisions

Ted Hardie <ted.ietf@gmail.com> Sat, 16 February 2013 00:58 UTC

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Date: Fri, 15 Feb 2013 16:58:12 -0800
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From: Ted Hardie <ted.ietf@gmail.com>
To: Michael Tuexen <Michael.Tuexen@lurchi.franken.de>
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Cc: Randell Jesup <randell-ietf@jesup.org>, "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Data Channel Negotiation and reopening of decisions
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On Fri, Feb 15, 2013 at 1:02 PM, Michael Tuexen
<Michael.Tuexen@lurchi.franken.de> wrote:
> On Feb 15, 2013, at 7:04 PM, Ted Hardie wrote:

> Martin suggests to have no control protocol for opening data channels.
> So there is nothing like an INIT message on a stream.
The presence of the data channel is sort-of a self-INIT, though; if you get a
data channel that re-uses existing Stream Identifiers, you could still error out
(not pleasantly mind).  But this is likely moot, see below>

> He would occasionally end up with one data channel instead of two.
> Systems, not behaving as expected *occasionally*, is a bad thing for
> me. I consider this a bug and it much harder to debug if it only
> occurs occasionally. It is even worse, if the developer hasn't made
> any mistake...

That this could result in one data channel where two were wanted is what I
was missing; I agree that this would be bad, whether occasional or not.  Having
a second data channel turn up when you were expecting one has a much
easier fix.

regards,

Ted


>
> For me, it should be clear how a data channel is set up, used,
> and teared down. Yes, things can go wrong on the wire (connection
> drop or so), but the API provides error handling. But we shouldn't
> come up with a solution which works most of the time. For specific
> applications this might be most of the time or even always.
>
> Best regards
> Michael
>>
>> regards,
>>
>> Ted
>>
>