Multicast Virtual Private Network (MVPN): Using Bidirectional P-Tunnels
draft-ietf-bess-mvpn-bidir-04

IESG/Authors/WG Chairs:

IANA has reviewed [draft-enter-here], which is currently in Last Call, and has the following comments:

We understand that this document doesn't require any IANA actions.

While it is helpful for the IANA Considerations section of the document to remain in place upon publication, if the authors prefer to remove it, IANA doesn't object.

If this assessment is not accurate, please respond as soon as possible.

The following Last Call announcement was sent out:

From: The IESG
To: IETF-Announce
CC:
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (MVPN: Using Bidirectional P-Tunnels) to Proposed Standard


The IESG has received a request from the BGP Enabled Services WG (bess)
to consider the following document:
- 'MVPN: Using Bidirectional P-Tunnels'
  as Proposed Standard

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf@ietf.org mailing lists by 2015-03-18. Exceptionally, comments may be
sent to iesg@ietf.org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract

  A set of prior RFCs specify procedures for supporting multicast in
  BGP/MPLS IP VPNs.  These procedures allow customer multicast data to
  travel across a service provider's backbone network through a set of
  multicast tunnels.  The tunnels are advertised in certain BGP
  multicast "auto-discovery" routes, by means of a BGP attribute known
  as the "Provider Multicast Service Interface (PMSI) Tunnel
  attribute".  Encodings have been defined that allow the PMSI Tunnel
  attribute to identify bidirectional (multipoint-to-multipoint)
  multicast distribution trees.  However, the prior RFCs do not provide
  all the necessary procedures for using bidirectional tunnels to
  support multicast VPNs.  This document updates RFCs 6513, 6514 and
  6625 by specifying those procedures.  In particular, it specifies the
  procedures for assigning customer multicast flows (unidirectional or
  bidirectional) to specific bidirectional tunnels in the provider
  backbone, for advertising such assignments, and for determining which
  flows have been assigned to which tunnels.




The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-bess-mvpn-bidir/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-bess-mvpn-bidir/ballot/


The following IPR Declarations may be related to this I-D:

  http://datatracker.ietf.org/ipr/2405/

AD review
====

I am going to start IETF last call for this document. I just wanted to
say Thanks! It is exceptionally readable --  I approach mcast documents
with a certain amount of trepidation, but I didn't find anything in this
document that wasn't perfectly clear. Good job!

(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?

  Targeted RFC type is "Standard Track", as indicated in the title page header.
  This is appropriate given the content of the document which specifies a new
  protocol and corresponding procedures.

(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

  A set of prior RFCs specify procedures for supporting multicast in
  BGP/MPLS IP VPNs.  These procedures allow customer multicast data to
  travel across a service provider's backbone network through a set of
  multicast tunnels.  [...] However, the prior RFCs do not provide
  all the necessary procedures for using bidirectional tunnels to
  support multicast VPNs.  This document updates RFCs 6513 and 6625 by
  specifying those procedures. [...]

Working Group Summary

  The consensus for adoption back in 2011 was rough, with a few
  contributors disagreeing on the scope that bidir P-tunnels should apply to.
  This debate has settled down a long time ago and the document has
  evolved since; no disagreement was expressed in the last years, nor
  during the last calls.

Document Quality

  The document is believe to be of good quality by the shepherd. It can be
  noted that it was written by a co-autor of the base mVPN specs based on
  an understanding of underspecified areas, which are now addressed.
 
  It has been indicated that Cisco has implemented the two main methods
  described by these specs, the Flat Partitioned Method (with MP2MP LSPs)
  and the Unpartitioned method (with MP2MP LSPs and also with BIDIR-PIM).

  The document had two thorough reviews (by a WG contributor and by the
  shepherd), leading to substantive changes in the document.

Personnel

  Thomas Morin is the Document Shepherd.
  Adrian Farrel is 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.

The shepherd has also done a thorough review of the document leading to
modifications that are already incorporated, and believes that the document
is ready.


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

No concern.
In particular, a WG contributor which is not a co-author has done a thorough review of the document leading to some change.


(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.

No.


(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.

I have shared with the main author my view that the document (in particular section 1.2.2) would be better if it would factually state that these specs come as additional tools to bring improvements that are also addressed, although differently, in base specifications; but we didn't reach a conclusion on changes to address my comment.


(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.

Yes.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

Yes, one late disclosure was filled related to IPR of some of the co-authors, after WGLC, which lead WG chairs to do a second last call to offer the WG the opportunity to express a revised position on the draft.
No objection to proceed was heard.

(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 consensus represent a small subset of interested contributors, additionally to the group of authors.
It is symptomatic of the high specificity and technicity of the topic (multicast in VPNs), and should not, in itself be regarded as a sign of lack of relevance of the specifications.


(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.)

No.

(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

Idnits complains that "The document seems to lack the recommended RFC 2119 boilerplate, even if it appears to use RFC 2119 keywords -- however, there's a paragraph with a matching beginning. Boilerplate error?", but I found the corresponding text ok.

(other idnits issues were resolved during shepherd review)


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

N/A

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

Yes.

(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.

(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.

(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.

(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).


(no IANA action needed)

(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 IANA action needed)

(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.

N/A