Re: [rtcweb] Why is required to have local streams before running ICE gathering? (another SDP limitation?)

Eric Rescorla <ekr@rtfm.com> Fri, 14 June 2013 14:00 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Fri, 14 Jun 2013 06:59:22 -0700
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Subject: Re: [rtcweb] Why is required to have local streams before running ICE gathering? (another SDP limitation?)
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On Fri, Jun 14, 2013 at 4:53 AM, Iñaki Baz Castillo <ibc@aliax.net> wrote:

> 2013/6/13 Eric Rescorla <ekr@rtfm.com>om>:
> >> 1. There is agreement that there should be a mechanism to pre-specify
> >> the size of a candidate pool to gather, though I just glanced in the
> spec
> >> and I didn't see it. (May have missed it though).
> >
> >
> > I see that there still is some (not quite up to date) text here:
> >
> > Create an ICE Agent as defined in [ICE] and let connection's
> > RTCPeerConnection ICE Agent be that ICE Agent and provide it the STUN and
> > TURN servers from the configuration array. The ICE Agent will proceed
> with
> > gathering as soon as the IceTransports constraint is not set to "none".
> At
> > this point the ICE Agent does not know how many ICE components it needs
> (and
> > hence the number of candidates to gather), but it can make a reasonable
> > assumption such as 2. As the RTCPeerConnection object gets more
> information,
> > the ICE Agent can adjust the number of components.
>
>
> Hi Eric, thanks a lot for the information you provide.
>
> Is it feasible with the current API to ask for N ICE candidates prior
> to having the local SDP set as local descriptor in the PeerConnection?
>
>
That has been discussed (and I thought agreed upon) but I don't see
it in the spec.

-Ekr