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Shepherd writeup

(1) What type of RFC is being requested 

   Proposed Standard

(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

   Some MPLS labels have been allocated for specific purposes.  A block
   of labels (0-15) has been set aside to this end, and are commonly
   called "reserved labels". As there are only 16 of these special purpose 
   labels, caution is needed in the allocation of new special purpose labels,
   yet at the same time allow forward progress when one is called for.

   This document defines new procedures to follow in the allocation and
   retirement of special purpose labels, as well as a method to extend
   the special purpose label space.  Finally, this memo renames the IANA
   registry for these labels to "Special Purpose MPLS Label Values", and
   creates a new one called the "Extended Special Purpose MPLS Label
   Values" registry.

Working Group Summary

   no controversy. Some contructive discussion of the details. 

Document Quality

   The document has been well reviewed, and has been updated to reflect
   comments received in WG last call. Due to the nature of this document it
   needs to be published in final form (as an RFC) prior to implementation
   but authors and reviewers include multiple vendors who would need to 
   implement the extension to the special purpose label space. 


   Ross Callon is the document shepherd. The AD for MPLS (Adrian 
   Farrel) is co-author, and so the other routing AD (Stewart Bryant) will
   act as responsible AD.  

(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.

   The shepherd has read the document, has checked it against last call
   comments, and has run IDnits. There is one obsolete normative reference
   but this can be fixed along with any comments received during IETF last
   call or during final editting. 

(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed?  

   no concerns

(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.

   not applicable. 

(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.

   All authors have confirmed that they are not aware of any IPR on this

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR

   No IPR disclosures. 

(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?   

   solid 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.) 

   no threat of appeal. 

(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

   The reference to RFC 4020 should be updated to RFC 7120.

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.

   not applicable. 

(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?

   all normative references are to existing RFCs. 

(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. 

   no downrefs. All normative references are to proposed standard or BCP

(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.

   This document does not change the status of any other RFC. There are 
   12 previous RFCs, listed in section 4, that use the term "reserved labels". 
   This RFC changes the term to "special purpose labels" and thereful 
   updates these previous RFCs. 

(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 shepherd believes that the IANA considerations section is clear
   and consistent with the document. 

(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.

   no such sections.