Simulating Partial Mesh of Multipoint-to-Multipoint (MP2MP) Provider Tunnels with Ingress Replication
draft-ietf-bess-mvpn-bidir-ingress-replication-04

[Ballot comment]

I have one less and two more serious comments...

- Less seriously, "MP2MP tunnel" seems like a strange use of
language, I wondered if it might be better to call these an
MP2MP warren (as in rabbit warren, and of course bearing in
mind the ops-dir review:-)

- More seriously, this is another draft that simply has too
many acronyms and uses those too densely. For example, I just
find it really hard to believe that "If a PE, say PEx, is
connected to a site of a given VPN, and PEx's next hop
interface to some C-RPA is a VRF interface, then PEx MUST
advertises a (C-*,C-*-BIDIR) S-PMSI A-D route, regardless of
whether it has any local Bidir-PIM join states corresponding
to the C-RPA learned from its CEs" is a useful sentence to
implementers. IMO enough folks have commented on this aspect
that the wg would be wise to seriously consider the
readibility of their output.  I've worked on enough EU-funded
projects that had write-only documents to be worried if the
IETF starts to produce those.  (This is not a discuss since
I've been assured that this is not a problem for implementers,
and while I do accept that, I also continue to worry about
it.)

- I am simply not in a position to evaluate section 4. And nor
was the assigned secdir reviewer. The same point about density
and that making any secdir review hard to impossible was noted
by the secdir reviewer for draft-ietf-bess-mvpn-bidir. I don't
think it'd be valid for me to put on a discuss on the basis
that nothing this complex has "no new security issues" but it
was tempting.

Overall, I think it would be best if this were returned to the
wg asking for significant improvement in clarity for readers.

[Ballot comment]
This is not an easy document to read.  If it gave reasons, examples, and explained what it was accomplishing
with the information exchanged, that would probably help.

[Ballot comment]
A very small point, and not a big deal:  The abstract says, "This specification updates RFC 6514," presumably to meet the I-D nits question.  But it doesn't say what, specifically, is updated, and I don't get that clearly from reading the rest of the document either (I presume that someone who knows 6514 well would understand; I think the explanation is in the paragraph in the introduction that mentions Ingress Replication tunnels, and there's a paragraph in the middle of Section 3.1...).  Can the sentence be expanded just a little (keeping it as one sentence) to summarise what the update is?  I'm thinking along the line of, "This specification updates RFC 6514 by [changing the procedures with respect to [whatever]]."

[Ballot comment]
Here is Warren Kumari's OPS DIR review.
Summary: Ready, typo / grammar nits.

General:
I found this document to be very dense. At some point my brain started
dribbling out my ears and I largely gave up on trying to understand
the mechanism. This seems to be very much a niche application, and my
IP multicast and deep MPLS knowledge isn't up to the level of finding
issues with the logic.

Nits:

Abstract:
This document specifiess how
[O] specifiess
[P] specifies
[R] spelling

1: Introduction:
  With these two methods, all PEs of a particular VPN are separated
[O] all PEs
[P] all PEs (Provider Edge router)
[R] first use of acronym. The document does say it assumed familiarity
with terminology from [RFC5015], [RFC6513], [RFC6514], and [RFC7582],
but this is before that, and also expanding PE here will help people
understand if they want to continue reading...

(Via drafts-lastcall@iana.org): IESG/Authors/WG Chairs:

IANA has reviewed draft-ietf-bess-mvpn-bidir-ingress-replication-02, which is currently in Last Call, and has the following comments:

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

While it's often helpful for a document's IANA Considerations section to remain in place upon publication even if there are no actions, if the authors strongly prefer to remove it, IANA does not 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:  (Simulating "Partial Mesh of MP2MP P-Tunnels" with Ingress Replication) to Proposed Standard


The IESG has received a request from the BGP Enabled Services WG (bess)
to consider the following document:
- 'Simulating "Partial Mesh of MP2MP P-Tunnels" with Ingress Replication'
  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 2015-10-08. 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


  RFC 6513 described a method to support bidirectional C-flow using
  "Partial Mesh of MP2MP P-Tunnels".  This document specifiess how
  partial mesh of MP2MP P-Tunnels can be simulated with Ingress
  Replication, instead of a real MP2MP tunnel.  This enables a Service
  Provider to use Ingress Replication to offer transparent Bidir-PIM
  service to its VPN customers.  These specifications update RFC 6514.




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

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


No IPR declarations have been submitted directly on this I-D.

(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?

Standard Track (properly indicated in 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

  This specifies an alternate technique than what has already been described
  to transport Bidir-PIM multicast traffic of a multicast VPN across a provider network.

  RFC 6513 described a method to support bidirectional C-flow using
  "Partial Mesh of MP2MP P-Tunnels".  This document describes how
  partial mesh of MP2MP P-Tunnels can be simulated with Ingress
  Replication, instead of a real MP2MP tunnel.  This enables a Service
  Provider to use Ingress Replication to offer transparent BIDIR-PIM
  service to its VPN customers.

Working Group Summary

  No controversy.

Document Quality

  The document is of good technical quality.
  There is no known implementation yet, but one vendor has
  mentioned plans for implementing these specs.

Personnel

  Thomas Morin is the doc shepherd.
  Alvaro Retana is the responsible AD.

(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 review of the document, leading
only to minor editorial changes.

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

No concern, in particular because a review was made by a long-time contributor
on the topic which is not a co-author of the draft.

(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.

N/A

(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 concern.

(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.

No IPR was diclosed.

(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? 

Good consensus among a solid although small set of contributors
(two vendors on the draft and a third vendor supporting the proposal).

(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 issue here.

(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.

All nits checked and fixed.
The warning about the abstract and RFC6514 is bogus and can be ignored.

(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 issue here.

(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 downward reference.

(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 change of 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).

No IANA action.

(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.

N/A

(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

(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?

Standard Track (properly indicated in 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

  This specifies an alternate technique than what has already been described
  to transport Bidir-PIM multicast traffic of a multicast VPN across a provider network.

  RFC 6513 described a method to support bidirectional C-flow using
  "Partial Mesh of MP2MP P-Tunnels".  This document describes how
  partial mesh of MP2MP P-Tunnels can be simulated with Ingress
  Replication, instead of a real MP2MP tunnel.  This enables a Service
  Provider to use Ingress Replication to offer transparent BIDIR-PIM
  service to its VPN customers.

Working Group Summary

  No controversy.

Document Quality

  The document is of good technical quality.
  There is no known implementation yet, but one vendor has
  mentioned plans for implementing these specs.

Personnel

  Thomas Morin is the doc shepherd.
  Alvaro Retana is the responsible AD.

(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 review of the document, leading
only to minor editorial changes.

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

No concern, in particular because a review was made by a long-time contributor
on the topic which is not a co-author of the draft.

(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.

N/A

(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 concern.

(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.

No IPR was diclosed.

(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? 

Good consensus among a solid although small set of contributors
(two vendors on the draft and a third vendor supporting the proposal).

(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 issue here.

(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.

All nits checked and fixed.

The nit about RFC5378 can be ignore, the draft was first submitted well
after RFC5378 came to effect.

(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 issue here.

(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 downward reference.

(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 change of 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).

No IANA action.

(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.

N/A

(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