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Shepherd writeup

Shepherd write-up : draft-ietf-l2sm-l2vpn-service-model

(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?

Standards Track
This is an implementable YANG model
This is correctly indicated on the title page.

(2) The IESG approval announcement includes a Document Announcement
    Write-Up. Please provide such a Document Announcement Write-Up.

Technical Summary:

This document defines a YANG data model that can be used to configure
a Layer 2 Provider Provisioned VPN service.

This model is intended to be instantiated at management system to
deliver the overall service.  This model is not a configuration model
to be used directly on network elements, but provides an abstracted
view of the Layer 2 VPN service configuration components.  It is up
to a management system to take this as an input and generate specific
configurations models to configure the different network elements to
deliver the service.  How configuration of network elements is done
is out of scope of the document.

The data model in this document includes support for point-to-point
Virtual Private Wire Services (VPWS) and multipoint Virtual Private
LAN services (VPLS) that use Pseudowires signaled using the Label
Distribution Protocol (LDP) and the Border Gateway Protocol (BGP) as
described in RFC4761 and RFC6624.

Working Group Summary:

This has been a relatively quiet WG, but there has been useful and
technical discussion on the list. WG meetings have brought in a few
additional voices raising valuablee points. The WG has also held
virtual interim meetings to dig into the open technical issues.

Document Quality:

There is one known implementation in progress.
The document received a thorough review from Jan Lindblad as a YANG
expert. Jan was very familiar with the L3SM work and able to carry
this review across.


Adrian Farrel ( is the document shepherd
Benoit Claise ( the Responsible AD

(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 version of the document is ready for publication.
The document shepherd reviewed the previous version in detail
especially for English and clarity. The updates have significantly
improved the document.

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

No concerns.
WG last call was echoes to BESS, PALS, RTGWG, and NETMOD

(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.

The big requirements were for YANG review and for input from operators
who offer L2VPN services. Jan satisfied the first. The author team
themselves satisfy the second.

(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 concerns.
There ws debate (several times) about how this work rslates to
similar work being done by the MEF. This was discussed at WG
meetings and on the mailing list and the document shepherd is
comfortable that the work represents different approaches to
related topics rather than a competitive situation.

(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 except have so confirmed.

(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 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?

L2SM is a small WG.
The consensus is solid but there are only a few voices to be
raised. There has been no objection.

(10) Has anyone threatened an appeal or otherwise indicated
     extreme discontent?


(11) Identify any ID nits the Document Shepherd has found in
     this document.

There are no valid nits in revision -07

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


(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.

RFC 4664
RFC 7348

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


(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).

IANA considerations are good.

(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

(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.

YANG compilation checks have been performed.