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Shepherd writeup

Draft Title:  Requirements for Ethernet VPN (EVPN)
Draft Name: draft-ietf-l2vpn-evpn-req-04

(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?


This is the proper type of RFC as this is a requirements document.
The type of RFC is indicated in the title page header.

(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:

     The widespread adoption of Ethernet L2VPN services and the advent
of new applications for the technology (e.g., data center interconnect)
have culminated in a new set of requirements that are not readily
addressable by the current Virtual Private LAN Service (VPLS) solution.
In particular, multi-homing with all-active forwarding is not supported
and there's no existing solution to leverage Multipoint-to-Multipoint
(MP2MP) LSPs for optimizing the delivery of multi-destination frames.
Furthermore, the provisioning of VPLS, even in the context of
BGP-based auto-discovery, requires network operators to specify
various network parameters on top of the access configuration.
This document specifies the requirements for an Ethernet VPN
(EVPN) solution which addresses the above issues.

     Working Group Summary:

     This document is an L2VPN Working Group document, and has been
reviewed in the working group through multiple iterations of the draft.
There was considerable debate during and after the WG last call which
resulted in new revisions being issued to resolve various comments.

     Document Quality:

     The document provides a clear and concise set of requirements
for E-VPN - broken down into different requirement areas.  As a
requirements draft there is no protocol to implement.


     Document Shepherd: Giles Heron (
     Area Director: Stewart Bryant (

(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

The Document Shepherd did a full review of the text of version -03 of
the draft, leading to the authors issuing version -04 with various fixes -
which was subsequently reviewed by the Document Shepherd.  The
Document Shepherd did a scan through the mail archives and
previous IETF meeting minutes to review debates on the draft.

(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.

No specific concerns.

(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?


(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?

There was considerable debate during the WG last call, and also strong
indication of support for the draft (by 12 individuals).

(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.

One nit found due to an informative reference to a draft which has
been updated in the last few days.

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

No formal review required.

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

Yes.  The Document Shepherd checked all this as part of the document review.

(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?

No - all 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 - all normative references are upward.

(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.

No - no impact on status of existing RFCs.

(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).

The IANA considerations section simply says "None."  As a requirements
draft there is no protocol defined, and hence no actions are required.

(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.

No sections written in a formal language.