Re: [rtcweb] Review of draft-ietf-rtcweb-mdns-ice-candidates

Bernard Aboba <> Sat, 15 September 2018 01:00 UTC

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From: Bernard Aboba <>
Date: Fri, 14 Sep 2018 18:00:00 -0700
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To: youenn fablet <>
Cc: RTCWeb IETF <>, T H Panton <>
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Subject: Re: [rtcweb] Review of draft-ietf-rtcweb-mdns-ice-candidates
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On Fri, Sep 14, 2018 at 5:42 PM youenn fablet <> wrote:

> In that case, the camera/MUX device might act as a STUN/TURN server.

[BA] In the usage I have seen the sender is a PC or Mac brought in to run
the meeting; STUN/TURN servers are run by an infrastructure group and are

> It will probably expose all of its host candidates. Ditto if sender is a
> browser since getUserMedia is on.
> I would think the connection to be feasible through peer reflexive
> candidates without the receiver to expose its own host candidates to
> JavaScript.

[BA] The STUN/TURN servers are often placed in the DMZ rather than on the
corpnet so using addresses other than host candidates will result in
hairpinning or unnecessary relaying.

>> Is the sender sending the media to each receiver or are there some
>> receivers acting as senders to other receivers?
[BA] For a large meeting, there is typically a conference server (SFU)
which forwards video and mixes or forwards audio to the receivers, most of
whom never send.