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Shepherd writeup

: (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, since this provides updates to the BFD YANG module.

: (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 describes a profile for the Bi-directional Forwarding Detection
(BFD) protocol for "sessionless" applications.  This permits a single active
side to initiate a BFD session with a passive "unsolicited" side.  The
unsolicited side does not require per-session configuration.

An example of such a session is protecting the reachability of a static route's
nexthop by configuring BFD on the static route without requiring the device
with the target nexthop to have the other half of the session configured.

: Working Group Summary:
: Was there anything in WG process that is worth noting? For example, was there
: controversy about particular points or were there decisions where the consensus
: was particularly rough? 

This document was considered non-controversial and has been previously deployed
in multiple implementations.  Since the document includes an extension to the
BFD YANG module, publication was delayed until the dependent YANG module was on
its way to IETF publication as an RFC.

: 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, YANG 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? 

There are multiple implementations of this mechanism.  Since the BFD YANG module is
new (RFC 9127) as of this writeup, there are currently no implementations of the
augmentation module contained in this document. 

: Personnel:
: Who is the Document Shepherd? Who is the Responsible Area Director? 

Document Shepherd: Jeffrey Haas, BFD co-chair.
Responsible Area Director: John Scudder, Routing.

: (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. 

This document has been through multiple Working Group review cycles.  A number
of minor clarifications were done in the final revisions of the document as
part of resolving the last portion of Working Group Last Call comments.  These
revisions increased the clarity of the document.

: (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. 


: (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?

The IPR attestations from the authors are documented in this mail thread:

All authors have confirmed that there are no IPR declarations vs. the document.

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

The BFD Working Group has a small number of technically informed participants.
This document received good review from active Working Group members.

: (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 thorough. 

ID-Nits shows 3 long-line errors.  Since these errors are related to formatting style
for the YANG module, the shepherd would prefer that these are resolved by the 
RFC Editor as they normalize the module for publication.

Similarly, the error of a reference to RFC 8342 is being deferred for resolution by
the RFC Editor as part of their style choices for this document.

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

The YANG module in this document was reviewed by the YANG doctors and the
points raised had been resolved.

The publication of this document was deferred until the BFD YANG module was
ready to hit RFC.  (That RFC-to-be is RFC 9127.)

: (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. 


There was Working Group discussion as to whether this document would be an
update to RFC 5881.  After discussion within the working group and the Area
Director at the time, it was determined that there are no normative protocol
changes created in this document to that RFC.  This document merely documents a
profile of RFC 5881.

: (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 8126). 

The IANA considerations as currently present in the document were the result of
addressing review issues from Tom Petch.  The current text has been reviewed and
found to be consistent with the body of 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, YANG modules, etc.

YANG checks have been done as part of document review.

: (20) If the document contains a YANG module, has the module been checked with
: any of the recommended validation tools
: ( for syntax and
: formatting validation? If there are any resulting errors or warnings, what is
: the justification for not fixing them at this time? Does the YANG module comply
: with the Network Management Datastore Architecture (NMDA) as specified in
: RFC8342?

The module was verified with