Re: [MMUSIC] ice-options attribute: session- and media-level?

[Suhas Nandakumar <[e-mail]>]

Thanks for the responses Magnus and Christer.
The more I think about it, the more I am confused on having a media level
option.

Unfortunately, this section predatesme joining as a co-author and hence
Marc/Ari might have a better reasoning.

We can wait on them to respond or can go with session level only
ice-options and write a new spec if we decide a media level version is
needed in the future

Cheers
Suhas

On Mon, Apr 23, 2018 at 4:09 AM Magnus Westerlund <
[e-mail]> wrote:

> Hi,
>
> I have to say, that I don't quite understand the reasons for changing the
> ice-options attribute. ECN for RTP's ICE ECN capable path check procedure
> is not a good argument for the need for media level. The rtp+ecn option is
> a session level capability attribute, where the a=ecn-capable-rtp attribute
> indicates which media levels where the path shall be checked.
>
> However, if the consensus is to prepare for any potential future option
> that would use media level ICE options, then okay, but it is difficult to
> evaluate the changes without any clear requirements.
>
> However, the draft do need to be updated. I have to agree with Christer,
> the normative 2119 language affecting the rtp+ecn option thus results in an
> updates: RFC 6679. And in addition section 10.2 also seem to update or
> replace the registration rules in RFC 6336. Which of it is needs to be made
> explicit.
>
> And if one is to allow to use rtp+ecn option on media level then I think
> you need to define that better. As ecn+rtp option indicates an endpoint
> capability it is not clear what media level version of that means. You will
> clearly also need to tackle the meaning of the different option in an
> bundle group.
>
> Cheers
>
> Magnus
>
> Den 2018-04-23 kl. 09:12, skrev Christer Holmberg:
>
> Hi Suhas,
>
> >> Section 4.6 of draft-ietf-mmusic-ice-sip-sdp-20 defines the
> ‘ice-options’ attribute as both session- and media-level.
> >>
> >>However, there is no description of what it means to use the attribute
> on media-level. Does it mean that the indicated ICE extension is only used
> for that particular media stream?
> >
> > [Suhas] Section 10.2 defines explanation of each ice-options attributes
> for media-level and session level considerations.
> >
> https://tools.ietf.org/html/draft-ietf-mmusic-ice-sip-sdp-20#section-10.2
>
> That text is VERY confusing  - especially the stuff about “media-level
> attributes being MUST be aggregated on session-level”.
>
> Also, the text seems to define such “aggregation rules" for the “rtp+ecn”
> option. If so, shouldn’t the draft update RFC 6679?
>
> Related to that, the text says that the the “rtp+ecn” option can only be
> used on session-level if it applies to all media, otherwise it has to be on
> the media-level. How does that fulfil the “MUST aggregate to session-level”
> requirement?
>
> Regards,
>
> Christer
>
>
>
>
>
>
>> Also, section 5.12 of draft-ietf-mmusic-sdp-mux-attributes-16 indicates
>> the attribute as session only (“S”).
>>
>> Is there a need to define it as media-level attribute?
>>
>> Regards,
>>
>> Christer
>>
>>
>> _______________________________________________
>> mmusic mailing list
>> [e-mail]
>> https://www.ietf.org/mailman/listinfo/mmusic
>>
>>
>
>
> _______________________________________________
> mmusic mailing [e-mail]://www.ietf.org/mailman/listinfo/mmusic
>
>
> --
>
> Magnus Westerlund
>
> ----------------------------------------------------------------------
> Network Architecture & Protocols, Ericsson Research
> ----------------------------------------------------------------------
> Ericsson AB                 | Phone  [phone]Torshamnsgatan 23 <https://maps.google.com/?q=Torshamnsgatan+23&entry=gmail&source=g>           | Mobile [phone]
> SE-164 80 Stockholm, Sweden | mailto: [e-mail]
> ----------------------------------------------------------------------
>
>