Shepherd writeup

As required by RFC 4858, this is the current template for the Document 
Shepherd Write-Up.

Changes are expected over time. This version is 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?

Proposed Standard. This is necessary to make changes to the related IANA registries which have standards action policy.

(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:

Technical Summary

   This document requests IANA to mark BGP path attribute values 30, 31,
   129, 241, 242, and 243 as "deprecated". These values were found to be
   in use in the Internet, despite not having been allocated by IANA.
Working Group Summary

This document arises because as part of the development of the large communities specification, values 30 and 31 were discovered to be "squatted" on by fielded implementations. Subsequently, two other implementations were found to be "squatting" on the other values. There was some debate in the working group as to whether it was better to deprecate the code points or to somehow "punish" the offending implementers. One of the arguments in favor of deprecation was that pragmatically speaking, no implementer would reasonably want to use one of the tainted code points and if forced to do so, no operator would be excited to deploy the resulting feature. The deprecation process was identified as the appropriate one to allow IANA to flag them as unfit for use. There was good working group consensus for this position.

There was also a concern raised by Tom Petch  that "deprecated" is not a well-defined term in the IETF lexicon and that different working group members might understand it to mean different things. This concern was addressed by explicitly adopting the definition of "deprecated" used in draft-leiba-cotton-iana-5226bis. Thus there is no ambiguity as to what the working group agreed to.

Finally it's worth noting that as part of the working group discussion it was pointed out that it's possible for a "deprecated" value to later be assigned. This might become relevant if one of the implementations that is currently "squatting" on one of those values later is brought up to snuff to meet the requirements for proper allocation.

As a possibly-interesting point of trivia, all debate about this draft took place before and during the working group adoption call, there was no discussion during the working group last call, which was announced as a "silence gives assent" call immediately following the conclusion of the adoption call. (There was opportunity for WG members to object to the "silence gives assent" rules, nobody did.)

Document Quality

  Are there existing implementations of the protocol? Have a 
  significant number of vendors indicated their plan to 
  implement the specification? Are there any reviewers that 
  merit special mention as having done a thorough review, 
  e.g., one that resulted in important changes or a 
  conclusion that the document had no substantive issues? If 
  there was a MIB Doctor, Media Type or other expert review, 
  what was its course (briefly)? In the case of a Media Type 
  review, on what date was the request posted?
This is a trivial process document. It has received good WG attention including review by people associated with all parties "squatting" on the affected path attribute values.


  Who is the Document Shepherd? Who is the Responsible Area

Document Shepherd: John Scudder
Responsible Area Director: Alvaro Retana

(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 IESG.

I've carefully read each version of the document as it was prepared, and monitored the mailing list discussion. The document is ready for publication.

(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
took place.


(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
concerns here.

No concerns.

(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?   

Strong and active consensus was shown, see also the working group summary above.

(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 and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be

IDnits throws a "outdated reference" complaint for draft-ietf-idr-large-community;  this will be corrected as a matter of course when the document reaches RFC editor phase and is not worth revising the document for now, especially because draft-ietf-idr-large-community is in IESG review and further revisions are likely before this document is complete.

(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.


Although the values being deprecated are of course being used in implementations of various (draft, not RFC) specifications, none of the values are documented in those specifications, so this document does not update them.

(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).

This document is essentially nothing but an IANA Considerations section, as such the Document Shepherd's review was comprehensive and exhaustive.

(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.