Re: [MMUSIC] Partial Offer/Partial Answer draft - MIME type value

[Paul Kyzivat <[e-mail]>]

On 10/20/13 4:23 PM, Emil Ivov wrote:
> One more thought:
>
> Please understand that trickle ICE is NOT a session modification.

Isn't the session modified as a result of the trickle ICE? (E.g., end up 
using a different media address than it otherwise would have.)

And the use of trickle ICE can (I think) require that a subsequent offer 
be sent (or answered) differently than it would had trickle ice not been 
used.

And AFAIK everything that can be accomplished with trickle ICE could 
also be accomplished with Partial Offer/Answer. So the differences 
aren't functional ones. I presume that trickle ICE is expected to be 
faster, and/or easier to implement. (But easier to implement becomes 
moot if both need to be implemented.)

In my book those justify considering it a session modification.

	Thanks,
	Paul

> Please
> try to isolate the SDP syntax that it uses from general O/A. It is not
> part of it.
>
> Think of it as JSON if that would make thinks easier.
>
> Emil
>
> --sent from my mobile
>
> On 20 Oct 2013 22:18, "Emil Ivov" <[e-mail]
> <mailto:[e-mail]>> wrote:
>
>     Christer, "I tried to explain" to you that what you are saying has
>     been addressed and cannot happen. If you believe that there is a
>     specific situation that is still possible and is a problem, then
>     please describe that rather than continuing to suggest that things
>     don't work without any valid arguments whatsoever.
>
>     --sent from my mobile
>
>     On 20 Oct 2013 21:50, "Christer Holmberg"
>     <[e-mail]
>     <mailto:[e-mail]>> wrote:
>
>
>         Hi,
>
>          >> Example:
>          >>
>          >> 1. Alice sends an SDP Offer to Bob.
>          >>
>          >> 2. Bob sends the SDP Answer to Alice, with candidates A, B
>         and C.
>          >>
>          >> 3. After that, Bob sends, using trickle ICE, candidates D
>         and E to Alice.
>          >>
>          >> If Alice receives the SDP Answer first, and then the trickle
>         ICE request, she will assume that Bob first provided candidates
>         A, B and C (in the SDP Answer), and then added D and E (in the
>         trickle ICE request).
>          >>
>          >> If Alice receives the trickle ICE request first, and then
>         the SDP Answer
>          >
>          > Don't do that then.
>          >
>          > It's been pretty clear from the start that any session
>         *modification* mechanism that does not also contain the full
>         session state completely falls apart in the face of unordered
>         delivery. This is a fundamental information problem, and you
>         aren't going to write rules that somehow cause it not to be true.
>          >
>          > We haven't yet tackled how to send trickle ICE in SIP, much
>         less partial offers and partial answers. When we do, the only
>         way it's going to have any chance of working at all is by
>         requiring ordered delivery.
>
>         I totally agree, and my opinion (which I tried to explain to
>         Emil) is that it applies also to candidates.
>
>         Regards,
>
>         Christer
>