Re: [rtcweb] JSEP: Relaxing SDP O/A rules?

Martin Thomson <martin.thomson@gmail.com> Fri, 05 October 2012 23:19 UTC

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Date: Fri, 5 Oct 2012 16:19:57 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Christer Holmberg <christer.holmberg@ericsson.com>
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Subject: Re: [rtcweb] JSEP: Relaxing SDP O/A rules?
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On 5 October 2012 14:26, Christer Holmberg
<christer.holmberg@ericsson.com> wrote:
>>> Can I use the same local descriptor for every setLocal() call?
>>
>> My experience suggests that you can.  However, that's not stipulated
>> in the API specification, so it's not an ironclad guarantee.
>
> If it doesn't, and a new local descripor is created, you would need to send that one to the remote endpoint.

You don't create a new description, you just set one.  The only
problem arises when you can't set the local description because
something broke since you last set it.  (Maybe setting the answer
caused the browser to release something that you need to set the
offer.)

If that happens, you are hosed.  You could try to make a new
PeerConnection, but you'll have to resend your INVITE because you will
get a new set of candidates, ufrag, pwd, etc...