Subject: [cuss] Draft minutes for Sep-21-2011 Virtual Interim meeting

From: "Vijay K. Gurbani" <[email-masked]>
Date: Fri, 23 Sep 2011 17:31:10 -0500

Folks: The draft minutes for the Wed, Sep-21-2011 virtual interim
meeting are below.

As it turns out, the recording of the virtual interim cannot be
located, so the draft minutes are condensed from the notes taken
by our volunteers (thanks, Enrico and Paul).

There is a missing decision that can benefit from someone recalling
what the discussion culminated in.  The place where this missing
decision occurs can be found by searching for the string
    "<CHAIR: WHAT?>"

If someone recalls, please let me know.

Please go through the minutes and check for accuracy in my trans-
cription of the raw notes from our volunteers.  Any errors so
introduce remain mine.

Please send any corrections by Friday, October 7, 2011 or earlier.

Thanks.

--- Begin draft minutes
CUSS 3rd Virtual Meeting
Wednesday, Sep. 21, 2011.
10:00 AM US Central - 11:30 AM US Central

Attendees: 9 identified + 3 Call-in users

Minutes taken by Enrico Marocco and Paul Kyzivat

Agenda was bashed and accepted.

Administrivia, Chairs
=====================
Slides: http://www.standardstrack.com/ietf/cuss/cuss-interim-3/Agenda.pdf

The requirement draft (draft-ietf-cuss-sip-uui-reqs-05) has been through
two WGLCs and is currently in the PubReq state.  The AD (Gonzalo) has
reviewed it and has offered some comments on the list for clarification
on a couple of items (see
http://www.ietf.org/mail-archive/web/cuss/current/msg00246.html).

Keith wants to make sure that the REQ-8 does not place any burdens
on existing proxies.

Alan is confident that he can address these comments shortly and get
a new revision out.  The new revision will be used for a IETF LC.

The mechanism draft (draft-ietf-cuss-sip-uui-02) needs more reviews.
The date for moving this ahead to WGLC as agreed during Quebec City
was Sept-15.  The draft needs more volunteers to review it.

The ISDN UUI Service application usage specification deliverable
currently does not have a draft associated with it.  Keit Drage's
independent submission (draft-drage-cuss-sip-uui-isdn-01) is a
candidate.  Solicitations were sent out on the WG list to get more
candidate drafts, none emerged.  During the meeting it was decided
to adopt draft-drage-cuss-sip-uui-isdn as the deliverable.

It was expressed that the WG should ask for an 1-hour slot for Taiwan
and cancel if not needed (the chairs have put a request into the
system).  The attendess expressed some interest in meeting in Taiwan
to iron out any remaining issues with mechanism draft.  It was also
expressed that another virtual meeting before Taiwan be organized
(probably around end of October).

Mechanism draft, Alan Johnston
==============================
Slides: http://www.standardstrack.com/ietf/cuss/cuss-interim-3/Mechanism.pdf
Draft: http://tools.ietf.org/html/draft-ietf-cuss-sip-uui-02

Alan went through the changes from previous version.  There was some
discussion on whether the "app" parameter in the UUI production rule (see
slide 3) can be made mandatory.  Alan noted that while this parameter
is needed for the ISDN use case, its utility on other usages is not clear.
No decision reached and further talks to proceed on the mailing list.

Paul asked on expanding the ABNF to include quoted-string as well as a
token for the uui-data production rule (see slide).  This was agreed to.

Keith asked whether the order of the parameters can be reversed when
expressing them as ABNF; Alan agreed to do so.

Keith and Alan agreed to exclude rfc3325 (Private Extensions to SIP for
Asserted Identity within Trusted Networks) when determining sources of UUI
headers but include P-A-I as a possible source.

There was a longer discussion on H-I and ISDN use case.  There were two
points to consider: (1) Decide whether ISDN package would allow 
redirects, and
(2) if a redirect were to occur and overrides the UUI, how would this
be detected?  Should it be prevented?  Or is it acceptable?  There was a
reasonable amount of discussion that culminated in <CHAIR: WHAT?>

It was also decided that during WGLC, sipcore would be invited to review
the document in the context of 4244bis usage.

Paul noted that the term "application" is ambiguous.  There is a thread
underway on the list to reach consensus on how this term is used in
the mechanism draft (see
http://www.ietf.org/mail-archive/web/cuss/current/msg00259.html).

ISDN Usage Draft, Keith Drage
=============================
Slides: 
http://www.standardstrack.com/ietf/cuss/cuss-interim-3/ISDN-Drage.pdf
Draft: http://tools.ietf.org/html/draft-drage-cuss-sip-uui-isdn-01

Keith Drage presented the draft.  Most comments on the draft were about
clarifying existing text:
   - Current text suggests that use in initial INVITE allows general
     usage within dialog, not just in response to the invite or in BYE.
     But other text contradicts this.
  - Section 6 is confusing by its use of 128 as the size limit, because
    sthe limit with protocol discriminator is 129.

The chairs noted that the last charter item --- ISDN UUI Service application
usage --- does not have a draft assigned as a deliverable.  A call for other
candidate drafts went out on Sept-08-2011 (see
http://www.ietf.org/mail-archive/web/cuss/current/msg00234.html) but no
other drafts have been put forth.  Given that there are no other candidate
drafts, the chairs asked attendees to express any reservations if this draft
(i.e., draft-drage-cuss-sip-uui-isdn-01) was to be adopted as a
deliverable to ISDN UUI Service application usage specification charter 
item.
There were no reservations expressed by the attendees.  Therefore, after
ratifying this decision on the mailing list, Keith will be asked to submit
a WG -00 version.

The meeting adjourned.
================================================================================
Note takers: Enrico Marocco and Paul Kyzivat

Raw notes:
  - Notes from Paul are archived at
    http://www.ietf.org/mail-archive/web/cuss/current/msg00258.html
  - Notes from Enrico appear below.

CUSS WG, September 21, 2011
Virtual interim meeting

Chairs: Vijay Gurbani and Enrico Marocco

Area Director: Gonzalo Camarillo

About 10 participants.

The meeting will be recorded.

Agenda
------

Vijay presents the agenda and status of the WG. Requirements are almost 
done.

   Alan Johnston: Gonzalo posted a few comments to the list, no major
issues. Minor issues with REQ-8, in particular make clear that the
intermediaries should not be expected to understand UUI. Keith Drage:
make clear that only endpoints are supposed to understand UUI. Alan:
early next week at the latest will provide text. Gonzalo: the draft should
be clear whether the mechanism affects routing. Don't care what way we
go, as long as its clear. Paul Kyzivat: we should not preclude proxies do
whatever they like, as long as we don't make that required. Keith: agrees.
Gonzalo: just clarify that this does not affect SIP routing. Vijay: Gonzalo,
do we need another WGLC after that change? Gonzalo: no, once it's done,
will move it on.

Mechanism draft needs more review, please volunteer. The ISDN UUI usage
item is the only charter item with no WG draft, and only one candidate
individual draft (Keith's); plan is to adopt it.

Any one has opinions about meeting in Taiwan?

   Martin Dolly: won't be in TW because of the conflict with 3GPP.

   Alan: would be good to meet.

Mechanism draft
---------------

Alan presents the mechanism draft. We need some review so that we can
go to WGLC.

   Keith: we can make the app parameter mandatory. Alan: it is certainly
needed for the ISDN use case, but am not sure other usages will require
it. Paul: don't have an opinion, but there can be issues with other
schemas. (Further discussion among Paul, Alan, Keith and James.)

   Keith: can the order of the parameters be reversed in ABNF, seems more
logic? Alan: yes.

   Keith: am fine with the rules for inserting UUI in requests and
responses, except that they exclude 3325. Alan: we can add P-Asserted-ID
as a source of UUI.

   Paul: the intent is SHOULD strenght? Alan: yes. Keith: in the ISDN UUI
added in a forward is indistinguishable from one inserted at the origin.
History-Info could cause interop issues. Alan: not sure we should forbid
it because the ISDN does not support it. Paul: do you want to forbid
H-I for UUI? (Note taker got disconnected for a couple of minutes.) Will
discuss on the list.

The draft references 4244bis even if it does not use any of the changes.
Will keep the fresh ref unless it holds it back.

   Keith: at some point we may need a review from SIPCORE.

   Paul: the term "applications" is ambiguous in guidelines. Is "call center
product" an application? Or is it a deployment using UUI? Alan: we don't
fully know this until we receive proposals for applications. The only one
we have is ISDN. Paul: it may be useful to explain what we mean by that.
Alan: would prefer not to narrow the scope of applications too much.
I don't know how we can do that now. We can add a minimum set of
guidelines. We'll make sure that we are consistent about the use of
"applications".

   Keith: not really convinced the ISDN usage needs a media tag. Paul:
either you need a feature tag or you don't.

ISDN usage draft
----------------

Keith presents the ISDN usage draft.

   Paul: confused about some of the wording, e.g. "you must use it in
invite only" and then "in any other in-dialog message". Keith: it could be
in re-INVITE, or an empty UUI. Paul: in section 7 you say initial INVITE.
Alan: seems like the ISDN is using the empty UUI for discovering UUI 
support.
It still seems the right thing to do, from the SIP perspective you are
still conveying end-to-end info.

   Paul: section 6 is a little confused.

   Alan: this draft will create the first entries in the app and content
parameters IANA registries.

Vijay: if anyone is opposed to adopting this draft as WG item, please
speak now.

   No one opposed.

The group will have another meeting before Taipei, tentatively during the
week starting on Oct. 24, and will meet live at IETF 82.

--- End draft minutes