Re: [MMUSIC] 1-week WGLC on Section 7.6 (3PCC Considerations) in draft-ietf-mmusic-rfc8843bis-06

[Roman Shpount <[e-mail]>]

Paul,

There is already the following language there:

When the BUNDLE mechanism is used, an initial BUNDLE Offer is constructed
using different rules than subsequent BUNDLE Offers, and it cannot be
assumed that a UA is able to correctly process a subsequent BUNDLE Offer as
an initial BUNDLE offer.  Therefore, the  3PCC controller SHOULD rewrite
the subsequent BUNDLE Offer into a valid initial BUNDLE Offer, following
the procedures in Section 7.2, before it forwards the BUNDLE Offer to a
UA.  In the rewritten BUNDLE Offer the 3PCC controller will set the port
value to zero (and include an SDP 'bundle-only' attribute) for each "m="
section within the BUNDLE group, excluding the offerer-tagged "m=" section.
_____________
Roman Shpount


On Mon, Nov 29, 2021 at 11:59 AM Christer Holmberg <christer.holmberg=
[e-mail]> wrote:

> Hi Paul,
>
> For #2, exactly where would you like to put that sentence?
>
> Regards,
>
> Christer
>
> ------------------------------
> *From:* mmusic <[e-mail]> on behalf of Paul Kyzivat <
> [e-mail]>
> *Sent:* Monday, November 29, 2021 6:57 PM
> *To:* [e-mail] <[e-mail]>
> *Subject:* Re: [MMUSIC] 1-week WGLC on Section 7.6 (3PCC Considerations)
> in draft-ietf-mmusic-rfc8843bis-06
>
> Christer,
>
> #1 seems fine to me.
>
> For #2 I think it would be helpful to expand the new text. E.g., add:
>
> "The 3PCC controller may want to take actions to mitigate this problem."
>
> That at least puts it on warning while not getting into the details of
> *how* to work around the problem.
>
>         Thanks,
>         Paul
>
> On 11/27/21 4:33 PM, Christer Holmberg wrote:
> > Hi,
> >
> > Is everyone else ok with the changes?
> >
> > Change #1:
> >
> > Change ‘Offer’ and ‘Answer’ to ‘offer’ and ‘answer’ throughout the
> document.
> >
> > Change #2:
> >
> > OLD:
> >
> >     In some 3rd Party Call Control (3PCC) scenarios a new session will be
> >
> >     established between an endpoint that is currently part of an ongoing
> >
> >     session and an endpoint that is currently not part of an ongoing
> >
> >     session.  The endpoint that is part of a session will generate a
> >
> >     subsequent SDP Offer that will be forwarded to the other endpoint by
> >
> >     a 3PCC controller.  The endpoint that is not part of a session will
> >
> >     process the Offer as an initial SDP Offer.
> >
> >     The Session Initiation Protocol (SIP) [RFC3261
> > <https://datatracker.ietf.org/doc/html/rfc3261>] allows a User Agent
> >
> >     Client (UAC) to send a re-INVITE request without an SDP body
> >
> >     (sometimes referred to as an empty re-INVITE).  In such cases, the
> >
> >     User Agent Server (UAS) will include an SDP Offer in the associated
> >
> >     200 (OK) response.  If the UAS is a part of an ongoing SIP session,
> >
> >     it will include a subsequent offer in the 200 (OK) response.  The
> >
> >     offer will be received by a 3PCC controller (UAC) and then forwarded
> >
> >     to another User Agent (UA).  If the UA is not part of an ongoing SIP
> >
> >     session, it will process the offer as an initial SDP Offer.
> >
> > NEW:
> >
> >     In some 3rd Party Call Control (3PCC) scenarios a new session will be
> >
> >     established between an endpoint that is currently part of an ongoing
> >
> >     session and an endpoint that is not currently part of an ongoing
> >
> >     session. In this situation the endpoint that is not part of a
> session,
> >
> >     while expecting an initial offer, can receive an SDP offer created as
> >
> >     a subsequent offer. The text below describes how this can occur with
> >
> >     the Session Initiation Protocol (SIP)[RFC3261
> > <https://datatracker.ietf.org/doc/html/rfc3261>].
> >
> >     SIP allows a User Agent Client (UAC) to send a re-INVITE request
> > without
> >
> >     an SDP body (sometimes referred to as an empty re-INVITE). In such
> > cases,
> >
> >     the User Agent Server (UAS) will include an SDP offer in the
> associated
> >
> >     200 (OK) response, and when the UAS is a part of an ongoing SIP
> session,
> >
> >     this offer will be a subsequent offer. This offer will be received
> >
> >     by the 3PCC controller (UAC) and then forwarded to another User
> > Agent (UA).
> >
> >     When that UA is not part of an ongoing SIP session, as noted above,
> >
> >     it will process the offer as an initial SDP Offer.
> >
> > Regards,
> >
> > Christer
> >
> > *From:*mmusic <[e-mail]> *On Behalf Of *Justin Uberti
> > *Sent:* torstai 25. marraskuuta 2021 1.16
> > *To:* Christer Holmberg <[e-mail]>
> > *Cc:* Flemming Andreasen <fandreas=[e-mail]>; mmusic
> > <[e-mail]>
> > *Subject:* Re: [MMUSIC] 1-week WGLC on Section 7.6 (3PCC Considerations)
> > in draft-ietf-mmusic-rfc8843bis-06
> >
> > Good suggestion, that works for me.
> >
> > On Wed, Nov 24, 2021 at 3:17 AM Christer Holmberg
> > <[e-mail] <mailto:[e-mail]
> <[e-mail]>>>
> > wrote:
> >
> >     Hi,
> >
> >     Maybe we instead of saying “as described below” could say ”The text
> >     below describes how this can occur with SIP”.
> >
> >     That way the 1^st paragraph remains independent from SIP.
> >
> >     Regards,
> >
> >     Christer
> >
> >     *From:*Roman Shpount <[e-mail] <mailto:[e-mail]
> <[e-mail]>>>
> >     *Sent:* tiistai 23. marraskuuta 2021 20.54
> >     *To:* Justin Uberti <[e-mail]
> >     <mailto:[e-mail]
> <[e-mail]>>>
> >     *Cc:* Christer Holmberg <[e-mail]
> >     <mailto:[e-mail]
> <[e-mail]>>>; Flemming Andreasen
> >     <fandreas=[e-mail]
> >     <mailto:[e-mail] <[e-mail]>>>;
> mmusic <[e-mail]
> >     <mailto:[e-mail] <[e-mail]>>>
> >     *Subject:* Re: [MMUSIC] 1-week WGLC on Section 7.6 (3PCC
> >     Considerations) in draft-ietf-mmusic-rfc8843bis-06
> >
> >     Justin,
> >
> >     Part of the reason for the non-SIP language and renaming the
> >     section was to make it clearer that it can apply to WebRTC, not just
> >     SIP. I think the goal here is to come up with the language that can
> >     be referenced from the JSEP draft, which should reduce your work.
> >
> >     _____________
> >     Roman Shpount
> >
> >     On Tue, Nov 23, 2021 at 1:29 PM Justin Uberti
> >     <[e-mail]
> >     <mailto:[e-mail]
> <[e-mail]>>> wrote:
> >
> >         On Tue, Nov 23, 2021 at 2:00 AM Christer Holmberg
> >         <[e-mail]
> >         <mailto:[e-mail]
> <[e-mail]>>> wrote:
> >
> >             Hi,
> >
> >             >>>1) for some reason, "offer" has been replaced with
> "Offer" throughout the document. This is a minor nit, but seems incorrect
> to me.
> >             >>
> >             >> I did that, because in the previous version we already
> used "BUNDLE Offer", so I thought I'd do it to be consistent.
> >             >
> >             > The problem though is that "answer" still is in lowercase
> so that introduces its own inconsistency.
> >
> >             Good catch. I was actually going to change that too, but now
> >             realized I forgot to.
> >
> >             I have no strong opinion regarding whether we use upper- or
> >             lowercase, as long as we are consistent.
> >
> >             > Generally I think we should avoid capitalization of common
> words to avoid confusion.
> >
> >             I can change everything to lowercase.
> >
> >         Sounds good.
> >
> >
> >             ---
> >
> >             >>>2) The first two paragraphs of 7.6 say similar things and
> it's not clear to me why they both exist. Here is my suggested revision:
> >             >>
> >             >> The first paragraph is more general, while the second
> paragraph describes how it is realized in SIP.
> >             >
> >             > Understood, but I feel like that intent was not totally
> clear in the current text.
> >
> >             I am mostly fine with your suggested modification.
> >
> >             However, as we don't really talk about "offer semantics"
> >             elsewhere in the document, perhaps:
> >
> >             "In this situation the endpoint that is not part of a
> >             session can receive an SDP offer, created as a
> >             subsequent offer, while expecting an initial offer, as
> >             described below."
> >
> >         That works. It might be easier to understand with the "while
> >         expecting an initial offer" clause first:
> >
> >         "In this situation the endpoint that is not part of a session,
> >         while expecting an initial offer, can receive an SDP offer
> >         created as a
> >
> >         subsequent offer, as described below."
> >
> >         But I am fine either way.
> >
> >             Regards,
> >
> >             Christer
> >
> >
> >
> >
> >
> >             OLD:
> >
> >                 In some 3rd Party Call Control (3PCC) scenarios a new
> >             session will be
> >                 established between an endpoint that is currently part
> >             of an ongoing
> >                 session and an endpoint that is currently not part of an
> >             ongoing
> >                 session.  The endpoint that is part of a session will
> >             generate a
> >                 subsequent SDP Offer that will be forwarded to the other
> >             endpoint by
> >                 a 3PCC controller.  The endpoint that is not part of a
> >             session will
> >                 process the Offer as an initial SDP Offer.
> >
> >                 The Session Initiation Protocol (SIP)
> >             [https://datatracker.ietf.org/doc/html/rfc3261
> >             <https://datatracker.ietf.org/doc/html/rfc3261>] allows a
> >             User Agent
> >                 Client (UAC) to send a re-INVITE request without an SDP
> body
> >                 (sometimes referred to as an empty re-INVITE).  In such
> >             cases, the
> >                 User Agent Server (UAS) will include an SDP Offer in the
> >             associated
> >                 200 (OK) response.  If the UAS is a part of an ongoing
> >             SIP session,
> >                 it will include a subsequent offer in the 200 (OK)
> >             response.  The
> >                 offer will be received by a 3PCC controller (UAC) and
> >             then forwarded
> >                 to another User Agent (UA).  If the UA is not part of an
> >             ongoing SIP
> >                 session, it will process the offer as an initial SDP
> Offer.
> >
> >             NEW:
> >
> >                 In some 3rd Party Call Control (3PCC) scenarios a new
> >             session will be
> >                 established between an endpoint that is currently part
> >             of an ongoing
> >                 session and an endpoint that is not currently part of an
> >             ongoing
> >                 session.  In this situation the endpoint that is not
> >             part of a session
> >                 can receive SDP with subsequent offer semantics in an
> >             initial
> >                 SDP Offer, as described below.
> >
> >                 The Session Initiation Protocol (SIP)
> >             [https://datatracker.ietf.org/doc/html/rfc3261
> >             <https://datatracker.ietf.org/doc/html/rfc3261>] allows a
> >             User Agent
> >                 Client (UAC) to send a re-INVITE request without an SDP
> body
> >                 (sometimes referred to as an empty re-INVITE).  In such
> >             cases, the
> >                 User Agent Server (UAS) will include an SDP offer in the
> >             associated
> >                 200 (OK) response, and when the UAS is a part of an
> >             ongoing SIP session,
> >                 this offer will be a subsequent offer. This offer will
> >             be received
> >                 by the 3PCC controller (UAC) and then forwarded to
> >             another User Agent (UA).
> >                 When that UA is not part of an ongoing SIP session, as
> >             noted above,
> >                 it will process the offer as an initial SDP Offer.
> >
> >             On Wed, Nov 17, 2021 at 3:16 PM Flemming Andreasen
> >             <fandreas=mailto:[e-mail]
> >             <mailto:[e-mail]
> <[e-mail]>>> wrote:
> >             Greetings MMUSIC
> >
> >             We previously submitted draft-ietf-mmusic-rfc8843bis for
> >             publication, however subsequently, the issue of 3rd Party
> >             Call Control came up and as a result of that, Section 7.6
> >             has been updated accordingly.
> >
> >             We are hereby starting a 1-week WGLC on Section 7.6 only in
> >             draft-ietf-mmusic-rfc8843bis-06.
> >
> >             If you have any comments on Section 7.6, please send those
> >             to the document authors and the MMUSIC mailing list by
> >             Wednesday November 24, 2021. If you review it but do not
> >             have any comments, please send a note to that effect as well.
> >
> >             Thanks
> >
> >             -- Flemming (MMUSIC co-chair)
> >             _______________________________________________
> >             mmusic mailing list
> >             mailto:[e-mail] <[e-mail]> <
> mailto:[e-mail] <[e-mail]>>
> >             https://www.ietf.org/mailman/listinfo/mmusic
> >             <https://www.ietf.org/mailman/listinfo/mmusic>
> >
> >         _______________________________________________
> >         mmusic mailing list
> >         [e-mail] <mailto:[e-mail] <[e-mail]>>
> >         https://www.ietf.org/mailman/listinfo/mmusic
> >         <https://www.ietf.org/mailman/listinfo/mmusic>
> >
> >
> > _______________________________________________
> > mmusic mailing list
> > [e-mail]
> > https://www.ietf.org/mailman/listinfo/mmusic
> >
>
> _______________________________________________
> mmusic mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/mmusic
> _______________________________________________
> mmusic mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/mmusic
>