Re: [MMUSIC] BUNDLE: Accept m- line, reject bundle

["Charles Eckel (eckelcu)" <[e-mail]>]

> -----Original Message-----
> From: [e-mail] [mailto:[e-mail]]
> On Behalf Of Christer Holmberg
> Sent: Friday, May 03, 2013 6:07 AM
> To: [e-mail]
> Subject: [MMUSIC] BUNDLE: Accept m- line, reject bundle
> 
> Hi,
> 
> 
> 
> Assume the following case:
> 
> 
> 
> 1.       An SDP offer contains an m- line associated with a BUNDLE
> group
> 
> 2.       The answerer wants to accept the m- line, but wants to reject it
> being in the specific BUNDLE group.
> 
> 
> 
> A few alternatives on how this could be achieved have been
> presented:
> 
> 
> 
> Alt 1.      The answerer accepts the m- line, but does not associate it
> with a BUNDLE group.
>
> 
> 
> Alt 2.      The answerer accepts the m- line, associates it with a
> BUNDLE group, and then sends a new offer which removes the m-
> line from the BUNDLE group.
> 
> 
> 
> Alt 3.      The answerer rejects the m- line, and then sends a new offer
> which adds the m- line outside a BUNDLE group.
> 
> 
> 
> In my opinion, Alt 1 does not work, at least not if the offer contains
> identical port values for the m- lines associated with the BUNDLE
> group. It would mean that the m- line is not added to a BUNDLE
> group, but still has the same port value (at least at the offerer side)
> as the m- lines in the BUNDLE group, which is not allowed.

True, but isn't that precisely what will happen if the answerer does not understand/support BUNDLE?
So at this point the offerer could choose to send a re-INVITE to use different receive ports for the non-bundled m-lines.
I would not put that burden on the answerer.

Cheers,
Charles
 
> 
> 
> So, my suggestion would be to specify that the answerer must use Alt
> 2 and/or Alt 3.
> 
> 
> 
> Comments?
> 
> 
> 
> Regards,
> 
> 
> 
> Christer