[sipcore] Proto writeup for draft-ietf-sipcore-subnot-etags-02

[Dean Willis <[e-mail]>]

SIPCORE chair Adam Roach has asked me to serve as the protocol  
shepherd for the subnot-etags work. Consequently, I've prepared the  
following writeup.


As required by RFC-to-be draft-ietf-proto-wgchair-doc-shepherding,  
this is
the current template for the Document Shepherd Write-Up. Changes are
expected over time. This version is dated September 17, 2008.

     (1.a) Who is the Document Shepherd for this document? Has the
           Document Shepherd personally reviewed this version of the
           document and, in particular, does he or she believe this
           version is ready for forwarding to the IESG for publication?

The document shepherd is Dean Willis. He has reviewed this document
and believes it is ready for publication.


     (1.b) Has the document had adequate review both from key WG members
           and from key non-WG members? Does the Document Shepherd have
           any concerns about the depth or breadth of the reviews that
           have been performed?

The document has been widely reviewed within the working group. Dale
Worley in particular provided some detailed analysis, and Eric
Rescorla also performed useful review leading to subtle changes in the
document. Paul Kyzivat provided further assistance with correcting the  
ABNF
during the final review process, and Adam Roach reviewed the document  
from
perspective of RFC 3265.


     (1.c) Does the Document Shepherd have concerns that the document
           needs more review from a particular or broader perspective,
           e.g., security, operational complexity, someone familiar with
           AAA, internationalization or XML?

No.


     (1.d) Does the Document Shepherd have any specific concerns or
           issues 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
           concerns here. Has an IPR disclosure related to this document
           been filed? If so, please include a reference to the
           disclosure and summarize the WG discussion and conclusion on
           this issue.

There are no shepherd concerns, and the shepherd is unaware of  
specific IPR
disclosures.

     (1.e) 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?

The document was widely reviewed within the working group between
August, 2007 and October, 2008.

     (1.f) 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
           entered into the ID Tracker.)

There appears to be no extreme discontent or significant conflict
surrounding the draft.

     (1.g) Has the Document Shepherd personally verified that the
           document satisfies all ID nits? (See
           http://www.ietf.org/ID-Checklist.html and
           http://tools.ietf.org/tools/idnits/). Boilerplate checks are
           not enough; this check needs to be thorough. Has the document
           met all formal review criteria it needs to, such as the MIB
           Doctor, media type and URI type reviews?

The shepherd checked idnits, validated BNF using BAP, and did the usual
visual review of the document. There are no formal criteria review for
this document.

     (1.h) Has the document split its references into normative and
           informative? 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
           strategy for their completion? Are there normative references
           that are downward references, as described in [RFC3967]? If
           so, list these downward references to support the Area
           Director in the Last Call procedure for them [RFC3967].

References appear to be appropriate.

     (1.i) Has the Document Shepherd verified that the document IANA
           consideration section exists and is consistent with the body
           of the document? If the document specifies protocol
           extensions, are reservations requested in appropriate IANA
           registries? Are the IANA registries clearly identified? If
           the document creates a new registry, does it define the
           proposed initial contents of the registry and an allocation
           procedure for future registrations? Does it suggest a
           reasonable name for the new registry? See [RFC5226]. If the
           document describes an Expert Review process has Shepherd
           conferred with the Responsible Area Director so that the IESG
           can appoint the needed Expert during the IESG Evaluation?

The IANA considerations appear to be appropriate.


     (1.j) Has the Document Shepherd verified that sections of the
           document that are written in a formal language, such as XML
           code, BNF rules, MIB definitions, etc., validate correctly in
           an automated checker?

The document contains only a trivial BNF for a SIP response code and
another very small addition for a message-header. The BNF was verified
using BAP.


     (1.k) 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:


Document Writeup


           Technical Summary

The Session Initiation Protocol (SIP) events framework enables
receiving asynchronous notification of various events from other SIP
user agents. This framework defines the procedures for creating,
refreshing and terminating subscriptions, as well as fetching and
periodic polling of resource state. These SIP Events Framework
procedures have a serious deficiency in that they provide no tools to
avoid replaying event notifications that have already been received by
a user agent. This specification defines an extension to SIP events
that allows the subscriber to condition the subscription request to
whether the state has changed since the previous notification was
received. When such a condition is true, either the body of a
resulting event notification or the entire notification message is
suppressed. This "conditioning" of the subscription requests uses the
well-known concept of entity tags (eTags).


           Working Group Summary

This document received extended working group review during a WGLC
period that exceeded one year in duration. One critical clarification
came up in this review period: this specification does not provide
"versioning history" for events; rather it lets a subscriber know
whether the current event state is consistent with the event state as
currently known by that subscriber. The distinction is subtle. For
example, if the subscriber knows of event state "A", but the actual
state has changed to "B" and then back to "A", the subscriber will not
be informed about the B state through this specification.

Following WGLC, the proto review process detected and corrected a
minor error in the ABNF, and further review by Adam Roach detected and
corrected problem related to suppressed NOTIFYs on initial dialogs.



           Document Quality


The Open Mobile Alliance SIMPLE Presence specification references this
document, and has done so for several years. Note that the most recent
OMA document  the shepherd could locate references
draft-ietf-sip-subnot-etags-03.txt rather than the current  
specification.