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Shepherd writeup

> (1) What type of RFC is being requested
>     Why is this the proper type of RFC?
>     Is this type of RFC indicated in the title page header?

This draft is requested for publication as a Proposed Standard.
This is appropriate for a YANG model that will be implemented and must
The status is properly indicated on the title page.

> (2) The IESG approval announcement includes a Document Announcement
>     Write-Up.
> Technical Summary:

This document defines an L3VPN Network YANG Model (L3NM) that can be
used for the provisioning of Layer 3 Virtual Private Network (VPN)
services within a service provider network.  The model provides a
network-centric view of L3VPN services.

L3NM is meant to be used by a network controller to derive the
configuration information that will be sent to relevant network
devices.  The model can also facilitate the communication between a
service orchestrator and a network controller/orchestrator.

> Working Group Summary:

There was no controversy.

This model was driven by implementers seeking to use the L3SM [RFC8309]
to provide L3VPN services using orchestrator and controller software.
They determined that an intermediary network-centric (rather than
service-centric) model was required, and they quickly built support
with other implementers.

During the later stages of work on this document, it was determined that
there was commonality between this model and a model for L2VPN.  The
common parts were pulled out into a separate model presented in another

> Document Quality:

This document notes four implementations: Nokia, Huawei, Infinera,

The document shepherd is aware of one other commercial implementation
and one prototype implementation.

> Personnel:

Adrian Farrel ( is the Document Shepherd
Rob Wilton ( iss the Responsible Area Director

> (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.

I reviewed this draft in detail during WG last call and all of the
issues I raised have been addressed. I have done a quick review of the
most recent version mainly focused on the changes. This version is
ready for publication.

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

No concerns. Indeed, the number of implementers participating has
resulted in a deep and broad review.

> (5) Do portions of the document need review from a particular or from
>     broader perspective? If so, describe the review that took place.

This document contains a YANG model and so review by YANG specialists
is in order.

An early YANG Doctor review was conducted on -03 by Radek Krejci and
the issues raised were fixed.

A subsequent YANG Doctor review on -07 at WG last call was also done by
Radek Krejci. It found only one simple nit, and this has been fixed in
the current version.

> (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?

No issues.

> (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.

All authors and contributors have so confirmed.

IPR protestations can be found on the thread

This records no known IPR from the full set of:
  Authors: Oscar Gonzalez de Dios, Mohamed Boucadair, Samier Barguil Giraldo,
  Qin Wu, Alejandro Aguado Contributors: Victor Lopez, Erez Segev

One Contributor (Luis Angel Munoz) notes no IPR on the thread

The final Contributor (Lucia Oliva) reports no IPR on the thread

> (8) Has an IPR disclosure been filed that references this document?

No IPR disclosed.

> (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?

OPSAWG is an odd WG in that it has several different communities of
interest that rarely cross-review work. As a result, judging broad
consensus in the WG is a challenge.

Nevertheless, the enthusiastic participation by a long list of authors
and contributors, the frequent open design team tele-meetings, and the
additional reviews from five people during last call with no major
objections, suggest good consensus.

While the design teams were well-attended, they left some visibility
holes concerning the work and failed to report back to the broader WG.
This has been corrected with regular readouts on the mailing list, as
well as requests to the mailing list for input on decisions.

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

No discontent voiced.

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

idnits is clean. The warnings have been checked and found to be benign.

> (12) Describe how the document meets any required formal review
>      criteria.

See (5) for YANG Doctor reviews.
YANG validation (in the datatracker) shows 0 errors, 0 warnings

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

Yes. Both normative and informative references are present.

> (14) Are there normative references to documents that are not ready
>      for advancement or are otherwise in an unclear state?

One normative reference is to draft-ietf-opsawg-vpn-common. This is a
partner document that is moving forward at the same time. It is ready
for advancement.

All other normative references are to RFCs.

> (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 downrefs.

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

No status changes.

> (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 section is simple.
It requests assignments from two clearly identified registries in
accordance with the allocation procedures for those registries.
No new registries are created.

> (18) List any new IANA registries that require Expert Review for
>      future allocations.


> (19) Describe reviews and automated checks performed by the Document
>      Shepherd to validate sections of the document written in a formal
>      language.

The datatracker YANG validation is clean. See (12) and (20)

> (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?
>      Does the YANG module comply with the Network Management Datastore
>      Architecture (NMDA) as specified in RFC8342?

The YANG validation results are clean.
To the best of my knowledge, the model complies with the NMDA.