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Shepherd writeup

Write-up-version: 2/24/2012 
status: 6/7/2019 
(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?  

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

   BGP specification [RFC4271] prescribes 'BGP next-hop reachability'
   as one of the key 'Route Resolvability Condition' that must be
   satisfied before the BGP bestpath candidate selection. This
   condition, however, may not be sufficient (as explained in the
   Appendix section) and desire further granularity.

   This document defines enhances the "Route Resolvability Condition"
   to facilitate the next-hop to be resolved in the chosen data plane.

Working Group Summary
   The chairs/shepherds lost this draft. 
    It was approved 9 years ago and there was not an implementation of the draft. 
   Due to IDR multiple interoperable implementations, this draft is now resurfacing. 

    One reminder was here:

   3 implementations: 
    The implementation report is at

    Currently there are 3 separate implementations (Cisco IOS-XR, Cisco IOS-XE, and Juniper)
    The chairs announced announced at IETF 103, interim (replacing IETF 104 meeting), 
    and IETF 105 regarding the 2 cisco implementations being counted as unique. 
    The WG accepted this work. 
    A question was indicated because it updates RFC4271 on the following:

  Initial Draft adoption:


Document Quality

  Are there existing implementations of the protocol?  3 implementations:

Last Shepherd report:
with follow up:
  original document shepherd: John Scudder
  current document Shepherd: Susan Hares
  responsible AD: 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.

John Scudder worked on this draft 6 years ago, but got lost. 
Susan Hares sought out implementation reports (see email links), 
 review, and finalized the shepherd's review. 

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

A current routing directorate review has not been made of this draft due to its age. 
It will be sent through routing-directorate.   The routing-directorate reviewer 
should be aware of the current implementations and if changes need to be made
indicate how implementations need to change. 

(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.

OPS directorate should review this draft as part of WG LC. 
It is implemented in 2 major vendors and deployed so the
if OPS-DIR has issues, they should address how operators should handle it. 

(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?  

This draft passed WG LC in 2009, but it has been waiting for 
implementations.    The security section requirements since 2009 
have been increased, so the shepherd requested additional changes
to that section.   These changes have been made in -12.txt version. 
Please note that the

(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.

Rajiv Asati

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

No IPR Statements made. 

(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 in 2009.  As time goes on waiting for implementation reports, 
the memory of those days weakens.  However, since 2 major vendors 
have implemented and deployed this RFC - the solid WG 
support from 2009 has been validated. 

(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

No nits. 

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

Not needed. 

(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 documents are read for advancement. 

One of the RFC reference requires additional comments 
since the IESG may be revewing draft-ietf-tunnel-encaps-12.txt 
at the same time as this draft. 

RFC5512 has been revised in draft-ietf-tunnel-encaps-12
due to a lack of implementation support for 
the BGP SAFI.   draft-ietf-tunnel-encaps-12.txt will obsolete 
RFC5512.  After the IESG approves the RFC publication, 
the IDR or BESS WG will prepare updates to a
group of RFCs that depend on RFC5512.  

Since this draft is implemented with RFC5512 referenced, 
it is appropriate to publish it as provided by the -12.txt  

IDR alignment with IETF mantra of  "rough consensus and running code" 
means that 2 implementations are required for publication. 
The same will be true of the updates of draft-ietf-tunnel-encaps-12.txt. 

I have tried to be detailed in this portion of the shepherd's report instead of brief. 
Please let me know if you have questions. 

(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 - see #14 for details. 

(16) Will publication of this document change the status of any
existing RFCs? 

Yes - this is linked to an optional update to RFC4271.   

Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? 

The RFC4271 is listed in the abstract. 

 (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).

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.

none required. 

(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 automated changes.