Re: [rtcweb] SDP_PRANSWER followed by SDP_OFFER scenario in JSEP

Roman Shpount <> Wed, 02 May 2012 15:40 UTC

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Date: Wed, 02 May 2012 11:40:09 -0400
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From: Roman Shpount <>
To: Harald Alvestrand <>
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Subject: Re: [rtcweb] SDP_PRANSWER followed by SDP_OFFER scenario in JSEP
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On Wed, May 2, 2012 at 9:35 AM, Harald Alvestrand <>wrote:

> Especially, I am worried about what the state of the peerconnection has to
> be before it is cloned, what the state of the peerconnection is after it is
> cloned, which peerconnection owns the various resources allocated (ports
> are the obvious part of it), and which peerconnection any streams (local or
> remote) attached to the peerconnection before the clone are attached to
> after the clone.
I thought there was a discussion on this list about using the same set of
ports, ICE candidates and turn connection across multiple peerconnections.
I am actually curious if there is ever a down side of using the same set of
ICE candidates for all the streams within the all peerconnections for a
given web session. It should be possible to disambiguate those streams
based on remote IP/port and SSRC.

The state that must to be replicated with the peerconnection is the latest
offer information. It would probably be less disruptive if peerconnection
has some sort of clone method instead of using a factory. It should be
possible to clone the connection between the time offer is generated and
the final answer is received.
Roman Shpount