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Shepherd writeup

Draft Title:  Requirements for Metro Ethernet Forum (MEF)Ethernet-Tree (E-Tree)
Support in L2VPN

Draft Name: draft-ietf-l2vpn-vpls-ldp-mac-opt-10

(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?

Proposed Standard

This is the proper type of RFC as the document defines new protocol extensions
and mac flush procedures for Virtual Private LAN Service (VPLS) and PBB-VPLS
services upon access topology changes.

(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:

   This document defines new procedures for MAC flushing in VPLS, H-VPLS and
   PBB- VPLS services upon access topology changes. These procedures cover
   additional additional scenarios to that covered RFC 4762 for H-VPLS. MAC
   flushing is a mechanism used to minimize traffic black-holing time when
   reachability to MAC addresses changes due to topology access changes.

   In particular, this document describes procedures for MTU-s initiated MAC
   flush when MTU-s is dual-homed to provider edges (PEs) over an active and
   standby Pseudowires, and the propagation of the MAC flush message over the
   VPLS core and processing at PEs.  It also describes a new optimized  MAC
   flush mechanism termed "negative flush" that enables PEs with instances of a
   VPLS instance to flush the MAC entries reachable via the PE where the
   topology change was experienced. This is opposed to the current procedure
   defined in RFC 4762 which cause all MAC addresses previously learned to be
   flushed except those that are learned from the PE that initiates the flush.
   Lastly, this document defines the MAC flush and optimized MAC flush for
   PBB-VPLS services.

Working Group Summary:

   This document is an L2VPN Working Group document. It has gone through a few
   iterations that addressed comments received from the Working group and
   comments from the WG chairs.

   The draft got good support when it was adopted as a WG draft. The Working
   Group last call got no feedback from the Working Group and the only comments
   that needed to be addressed were those of the WG chairs.

Document Quality:

   The document has OK quality. It is clear on the technical content and
   written with reasonable English and layout.

   The draft has authors from a couple companies that claim to have implemented
   the solution albeit no interoperability testing was done.


     Document Shepherd: Nabil Bitar (
     Area Director: Adrian Farrel (

(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 Shepherd did a full review of version 6 and version 8, and provided
comments to the authors that were addressed in versions 7 and 8  and last in
version 10, as described earlier.

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

The lack of feedback during the last call was a concern, but the document
content is sound. The document had good support early on. It may be worthwhile
undergoing routing directorate review as well.

(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.

There is an IP disclosure filed by Alcatel-Lucent against version 05 of this
document. It is ID # 1749. There was no working group discussion about this

(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?

The current draft is supported by individuals that had authored and contributed
to the draft. Few more supported the adoption of this draft as a Working Group
draft early on. There was no objection raised against this document.

(10) Has anyone threatened an appeal or otherwise indicated extreme discontent?
If so, please summarize 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.


(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 RFCs.

(15) Are there downward normative 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.

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 registry identified is that of LDP. The document requests the
allocation of a new LDP TLV named "MAC Flush Parameters" and two sub-TLVs.

(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.

This document requests code point for following LDP TLV:

   o  MAC Flush Parameters TLV.

   Also this document requests two Sub-TLV values for

   o  PBB BMAC List Sub-TLV 0x01 IANA TBA

   o  PBB ISID List Sub-TLV 0x02 IANA TBA

(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.