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Shepherd writeup

The MPLS Working Group request that 

        LDP Extensions to Support Maximally Redundant Trees

Is publsihed as an RFC on the Standards Track.

(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?

   We request publication as a Proposed Standard, the document header says
   "Standards Track".
   The document specifies extensions and procedures for a Standard Track 
   protocol (LDP) and Proposed Standard is the correct type of RFC.

(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

   The document specify an extensions to the Label Distribution
   Protocol (LDP) that support the creation of label-switched paths
   for Maximally Redundant Trees (MRT).  The most obvious use of MRT
   is for Fast-Resoute for IP/LDP uni- and multicast. This is 
   referred to as MRT-FRR.

   The document specifies this ability of LDP to advertise MRT 
   Capability and the associated behavior expected for LSRs (Label 
   Switching Routers) and LERs (Label Edge Routers) advertising the
   MRT Capability.

   MRT-FRR uses LDP multi-topology extensions and requires three
   different multi-topology IDs to be allocated from the MPLS MT-ID

Working Group Summary

  The working group support this document. The progress has been a
  bit slow, since we have been waiting for other MRT documents in 
  other working groups.

Document Quality

  We are aware of two prototype implementations of this protocol 
  specifiction. An implementation poll has been sent out to the 
  working group, as soon as we have more information we will update
  the shepherd write-up.
  The document has been through the normal wg process, no other types
  are necessary.


  Loa Andersson is the Document Shepherd
  Deborah Brungrard is the Responsible Area Director.

(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 document shepherd has reviewed the document several times
   - when the document were first posted as an individual document
   - when preparing the adoption as a working group document
   - when the documents in other working groups were in such a state
     that it no longer blocked the progress of this document
   - at working group last call

   This document is ready for publication, save for a small nit on 
   terminology on OSPF and IS-IS terminology on border routers. We 
   have agreed to fold this update in with the comments from the 
   RTG-DIR review.

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

   No such 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.

   No such revieews needed.

(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 such conserns.

(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 the authors have stated on the MPLS Working Group mailing list
   that they are unaware of any IPR that relates to this document.

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

   There are no IPR disclosures against this document.

(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? 

   LDP FRR and  LDP based MRT FRR are corner stones in the MPLS 
   protection architecture and has solid support in the working 

(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 such threats.

(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

   No nits identified, the nits tool points to two miscellaneous 
   - a weird spacing in the table of content, it seems to me that
     cam await the final RFC Editor editing
   - the nits tool also calim that the RFC 2119 boilerplate is 
     missing, it turns out the the boilerplate is there but that the
     text is not 100% what the boilerpalte is supposed to be. The 
     authors has been told to change the bolier plate to:

     The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
     document are to be interpreted as described in RFC 2119 [RFC2119].
     When the comments from the RTG-DIR is resolved.

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

   No such formal reviews required.

(13) Have all references within this document been identified as
either normative or informative?

   The references are correctly split, with the the exception of the
   reference to RFC 2119 that I think should be a normative

(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 too 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 down references, all normative references are to Proposed 
   Standard RFCs.

(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.

   There will be no status change for any other document when this is

(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 has reviewed the IANA section several times as the 
   document developed. The IANA section is clear and well sritten.

(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.

   No new IANA registries created.

(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 reviews necessary.