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 1 November 2019.
: (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? 

Type of RFC:
  Proposed Standard.

  Proposes extensions to RFC7752 for a new BGP-LS code points for Node
  Descriptor, Link Descriptor, Prefix Descriptor, and Attribute TLVs.

: (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:
   Seamless Bidirectional Forwarding Detection (S-BFD) defines a simplified
   mechanism to use Bidirectional Forwarding Detection (BFD) with large
   portions of negotiation aspects eliminated, thus providing benefits such
   as quick provisioning as well as improved control and flexibility to
   network nodes initiating the path monitoring.  The link-state routing
   protocols (IS-IS and OSPF) have been extended to advertise the Seamless
   BFD (S-BFD) Discriminators.

   This draft defines an extension to the BGP Link-state address-family to
   carry the S-BFD Discriminators information in a new BGP-LS Attribute TLV
   called the S-BFD Discriminators TLV. 

Working Group Summary:

: Was there anything in WG process that is worth noting? 

No, some minor additions. 

Please note that the revision of RFC7752 is progressing. 
WG consensus:
  The document generated little interest outside of the usual interested
  parties for BGP-LS related technologies on the IDR list.  The extension
  defined in this document is simple, and appropriate signaling for the
  S-BFD mechanism state that is required.

  The shepherd is also a co-chair of the BFD Working Group and confirms that
  the extension is appropriate for that technology.

Document Quality:

Implementations at:
  [Note - only one implementation listed here at Nokia. 
  Check with Huawei and Cisco for their implementations] 

  Who is the Document Shepherd: Jeffrey Haas
  Who is the 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. 

The document is of high quality and in need of only minor grammar or syntax
changes to utilize the terminology of dependent RFCs appropriately.

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

No.  The document is clear.

: (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. 

This document was brought to the attention of the BFD Working Group during
its lifetime.  No formal request has been made to the BFD Working Group.
The shepherd is a co-chair of BFD and finds the encodings in this document
suitable for the use of the base S-BFD RFC.

Further review can be sought, if desired by the IESG.

: (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 ordering of the Discriminators is of potential interest and concern as
it is under-specified.  Adding normative text addressing this concern has
the potential to have impact on existing deployments of this mechanism.

This issue was discussed during shepherd review.  It is agreed that the
documented behavior is consistent with that of the IGP extensions.

: (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?

Zhenbin Li

Shunwan Zhuang

Ketan Talaulikar

Sam Aldrin

Jeff Tantsura

Greg Mirsky

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

No 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? 

Normal active participants sent in support posts. 

: (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 threats or discontent over this document. 

: (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. )

Nits are all related to document being published in the prior year.  
No other nits.

: (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 IANA code point for the attribute defined in this document is vs. a
Specification Required registry and has passed requirements for early

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


Shepherd review of the current published document, version -04, might be
able to use a few additional informative references for clarity.

: (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. 


: (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). 

IANA has provided an early registration for the code point required for this
document.  The registration remains appropriate and can be stably assigned
using this RFC-to-be as a reference.

: (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 registries.   Early allocation on code point. 

: (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.

This document includes none of these items for 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?

No Yang modules at this time.