Re: [rtcweb] Fwd: New Version Notification for draft-uberti-rtcweb-rfc8829bis-00.txt

[Justin Uberti <[e-mail]>]

The problem though is that if you are setting bundle-only you also need to
zero the port, which opens up the whole can of worms with deployed
applications that we were hoping to avoid. Limiting it to IceRestart would
reduce the risk but not eliminate it.

It would be good to hear of at least one example of this causing an actual
problem before spending substantial energy here, I think. Note also that
this would be a change to BUNDLE, not to JSEP.

On Tue, Jul 13, 2021 at 10:55 AM Roman Shpount <[e-mail]> wrote:

> Justin,
>
> Part of the new BUNDLE syntax problem is that the offer generated during
> the session is not a valid initial offer, even for the endpoints that do
> support BUNDLE. There are m= lines with no candidates and no bundle-only
> tags. Even if we are not going to support unbundling in 3PCC scenarios, we
> should generate valid initial offers for BUNDLE-enabled endpoints.
>
> At the very least, my suggestion would be, when a new offer is generated
> after ICE restart is initiated (either due to the iceRestart option or ICE
> configuration changes), to set a bundle-only tag on the bundled m= lines.
>
> Best Regards,
> _____________
> Roman Shpount
>
>
> On Tue, Jul 13, 2021 at 1:43 PM Justin Uberti <
> [e-mail]> wrote:
>
>> Roman,
>>
>> I see what you are getting at. I suppose that was one benefit of the
>> other BUNDLE syntax, i.e., that all offers (not just the first) are always
>> understandable by a non-BUNDLE endpoint.
>>
>> That said, given the adoption of BUNDLE I tend to think that 3PCC to a
>> non-BUNDLE endpoint is increasingly a corner case, so it may not be worth
>> going to the trouble of trying to fix the SDP syntax and allowing for
>> mid-call unbundling.
>>
>> Note also that it is not clear to me how rtcp-mux would work in a similar
>> situation, i.e., when doing 3PCC to a non-rtcp-mux endpoint.
>>
>> Justin
>>
>> On Sat, Jul 10, 2021 at 8:45 PM Roman Shpount <[e-mail]> wrote:
>>
>>> On Sat, Jul 10, 2021 at 11:35 PM Justin Uberti <[e-mail]>
>>> wrote:
>>>
>>>> (To be clear, m= sections that are bundled will continue to be bundled
>>>> and will not participate in the restart.)
>>>>
>>>
>>> This is what I thought.
>>>
>>> How would one unbundle them if an offer needs to be generated for 3PCC
>>> (like an offer in response to an empty INVITE)? There is the iceRestart
>>> option for ICE to do this. Is there a need for something similar for the
>>> bundle to do the same thing? Please see draft-ietf-mmusic-rfc8843bis-04
>>> section 7.6 (
>>> https://www.ietf.org/archive/id/draft-ietf-mmusic-rfc8843bis-04.html#section-7.6)
>>> for more details.
>>>
>>> Please note that in the case of 3PCC an offer within an existing session
>>> for one call leg would be the initial offer for another call leg. After the
>>> latest change, an offer within the existing session is no longer a valid
>>> initial offer.
>>>
>>> Thank You,
>>> _____________
>>> Roman Shpount
>>> _______________________________________________
>>> rtcweb mailing list
>>> [e-mail]
>>> https://www.ietf.org/mailman/listinfo/rtcweb
>>>
>>