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 is requested as indicated in the title page header. 
This is the correct type of RFC since it describes it is useful to have 
the particular behavior it describes implemented in a consistent manner 
across different implementations. It is also consistent with the 
previous decisions to publish as Proposed Standard RFCs related to LFA, 
RLFA, and node-protecting LFA. 

(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

Transient forwarding loops can occur among routers using hop-by-hop
forwarding. This document describes a mechanism for link-state routing protocols
to prevent local transient forwarding loops in case of link failure.
This mechanism proposes a two-steps convergence by introducing a
delay between the convergence of the router adjacent to the topology
change and the network wide convergence.

Working Group Summary

The final version of the document has strong consensus in the WG. Input 
from the WG was incorporated in the document, which affected both the 
scope and substance of the document. 

Document Quality
  The document is of high quality.
  A Routing Area Directorate early review of draft-ietf-rtgwg-uloop-delay-01
  was done by Matthew Bocci.  It noted mainly grammatical problems, as well as a requesting a few 
  technical clarifications.  draft-ietf-rtgwg-uloop-delay-03 addressed both the
  grammatical and technical clarifications from the review.
  As discussed in the document, the mechanism described has at least three implementation
  and has been deployed in live networks.

  Document Shepherd: Chris Bowers
  Responsible Area Director: Alia Atlas

(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 was thoroughly reviewed by the document shephard.  Some issues
were found and discussed on the list with the authors and have been addressed.
The Document Shepherd thinks 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?

The Document Shepherd has no concerns in this respect.

(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 beyond the Routing Area Directorate review, which was already performed.

(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.

The Document Shepherd has no concerns in this respect.

(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 only aware of the following disclosures:

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

One IPR disclosure references this document, and it has been disclosed to the 
working group by the authors.  There has not been active discussion of the 
IPR diclosure.

(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?   

The final version of the document has strong consensus from the WG.

Early versions of the draft included mechanisms to deal 
with both link-down and link-up events.  The mechanism 
to deal with the link-up case was later removed from the draft in
an effort to solidify consensus on the mechanism to deal with 
the link-down case.

One issue that came up during the WG Last Call was the type of RFC being 
requested. Stewart Bryant suggested that the RFC should be informational 
since the behavior described is local to the PLR and therefore does not 
introduce a requirement for multiple routers to co-operate. However, 
several people pointed out or agreed with the observation the document 
is not qualitatively different from the LFA, RLFA, and node-protecting 
LFA RFCs which were all published as standards track. So publishing this 
draft as standards track would be consistent with the decision made on 
those drafts. Stewart indicated that this was not a sticking point and 
would accept the consensus of the WG. 

(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

All ID nits have been addressed as of draft-ietf-rtgwg-uloop-delay-06.

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

No additional formal reviews are required based on the document content.

(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?

There are no normative references in an unclear state.

(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. 

There are no downward normative references.

(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.

The publication of this document will not change the status of any
existing 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).

There are no IANA considerations.

(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.

There are no new IANA 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 sections of the document are written in a formal language.