Shepherd writeup for draft-ietf-sipcore-refer-explicit-subscription-02:
[This is based on the template version dated 24 February 2012.]
(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)? Why
is this the proper type of RFC? Is this type of RFC indicated in the
title page header?
This document is marked as Standards Track in the title page header,
and that seems appropriate, because it is defining new, optional,
(2) The IESG approval announcement includes a Document Announcement
Write-Up. Please provide such a Document Announcement Write-Up. Recent
examples can be found in the "Action" announcements for approved
documents. The approval announcement contains the following sections:
The Session Initiation Protocol (SIP) REFER request, as defined by
RFC3515, triggers an implicit SIP-Specific Event Notification
framework subscription. Conflating the start of the subscription
with handling the REFER request makes negotiating SUBSCRIBE
extensions impossible, and complicates avoiding SIP dialog sharing.
This document defines extensions to REFER to prevent the implicit
subscription and, if desired, replace it with an explicit one.
Working Group Summary
There was some controversy and difficulty in reaching agreement on this draft.
Before work on this draft and the companion draft (draft-ietf-sipcore-refer-
clarifications) commenced, some (notably 3GPP) made attempts to use existing
mechanisms (RFC4488) to avoid the need for GRUUs. That mechanism as insufficient
on its own, and so was enhanced with particular conventions. There was a desire
to maintain compatibility with that work. This led to careful word smithing.
That has been discussed at length within the WG. The results are now acceptable
to all parties.
[Are there existing implementations of the protocol? Have a
significant number of vendors indicated their plan to
implement the specification?]
I'm not aware of any implementations yet.
It is my understanding that 3GPP release 12 has a reference,
indicating that implementations can be expected.
This document has been thoroughly reviewed and discussed. Everyone
that had something to say has aired it.
The document shepherd is Paul Kyzivat.
The area director is Ben Campbell.
(3) Briefly describe the review of this document that was performed by
the Document Shepherd. If this version of the document is not ready
for publication, please explain why the document is being forwarded to
The shepherd was a SIPCORE chairman during the entire period while this
document was introduced and discussed. He has followed (and participated
in) the discussion and reviewed the document carefully.
(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed?
(5) Do portions of the document need review from a particular or from
broader perspective, e.g., security, operational complexity, AAA, DNS,
DHCP, XML, or internationalization? If so, describe the review that
(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.
(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it?
There is good consensus.
(10) Has anyone threatened an appeal or otherwise indicated extreme
discontent? If so, please summarise the areas of conflict in separate
email messages to the Responsible Area Director. (It should be in a
separate email because this questionnaire is publicly available.)
(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.
(13) Have all references within this document been identified as
either normative or informative?
(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state? If such normative
references exist, what is the plan for their completion?
(15) Are there downward normative references references (see RFC 3967)?
If so, list these downward references to support the Area Director in
the Last Call procedure.
(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.
It does *extend* RFC3515 in a backward compatible way.
That is clearly explained.
(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 5226).
The IANA considerations are all in good order.
(18) List any new IANA registries that require Expert Review for future
allocations. Provide any public guidance that the IESG would find
useful in selecting the IANA Experts for these new registries.
(19) Describe reviews and automated checks performed by the Document
Shepherd to validate sections of the document written in a formal
language, such as XML code, BNF rules, MIB definitions, etc.
The shepherd verified the ABNF using bap.