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 disclosure.

(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.