Internal BGP as the Provider/Customer Edge Protocol for BGP/MPLS IP Virtual Private Networks (VPNs)
RFC 6368

[Ballot discuss]
I think this should be an easy one.

Can an ATTR_SET include an ATTR_SET? Currently, that
appears to be allowed. I've no idea if that's intended
or not. Maybe clarify? If allowed, would that complicate
the stack push/pop model in the text?

[Ballot comment]
These ought to be pretty easy to fix up.  Most are about 2119 language usage.

#1) elide the reference from the abstract

#2) Section 4 contains the following:

  When a PE received route is imported into a VRF, its IGP metric, as
  far as BGP path selection is concerned, should be the metric to the
  remote PE address, expressed in terms of the service provider metric
  domain.

r/should/SHOULD?

#3) r/ATTR_SET is an optional transitive/ATTR_SET is an OPTIONAL transitive

#4) Section 5 contains the following:

  It
  should contain the autonomous-system number of the customer network
  that originates the given set of attributes.

r/should/SHOULD?

#5) Section 5 contains the following:

  BGP speakers that support the
  extensions defined in this document must also support RFC4893
  [RFC4893].

r/must/MUST?

#6) Section 5 contains the following:

  When
  present it should be ignored by the receiving PE.

r/should/SHOULD?

#7) Section 7 contains the following:

  Otherwise, in the case of an autonomous-
  system number mismatch, the set of attributes to be associated
  with the route shall be constructed as follows:

and

  When advertising the VRF route to an Exterior BGP peer, a PE
  router shall apply steps 1 to 4 defined above and subsequently
  prepend its own autonomous-system number to the AS_PATH attribute.

r/shall/SHALL ?

#8) Section 8 contains the following:

  It is recommend that different VRFs of the same VPN (i.e. in
  different PE routers) which are configured with iBGP PE-CE peering
  sessions use different Route Distinguisher values.

r/recommended/RECOMMENDED ?

also r/Route Distinguisher values/Route Distinguisher (RD) values

#9) In Section 8, expand NLRI

[Ballot comment]
The Gen-ART Review by Suresh Krishnan on 7-Jun-2011 includes two
  suggestions for improvement.
 
  (1) The authors readily accepted the first suggestion.  Please
  make sure the changes related to the first one make it into the
  document prior to publication.

  (2) The authors questioned the value of the second suggestion.  My
  personal preference would be to include a very general statement the
  need for protection against memory exhaustion attacks in the security
  considerations section, but I will not demand one.

[Ballot comment]
(1) Some acronyms aren't expanded - VRF was the one that
got me as well as ASBR. I guess implementers of this would
know but just in case.

(2) The diagram at the start of section 4 could be clearer.
I found it confusing anyway.

(3) last line of p8 - is that "should" or "SHOULD"? When
would it be ok to not contain the ASN of the customer?

(4) s/VPN network/VPN/ (Sorry, pet peeve of mine:-)

(5) When is it ok to include the NEXT_HOP attribute in
an ATTR_SET? Text says SHOULD NOT which implies there
are cases when its the right thing to do - documenting
(some of) those would be better.

[Ballot discuss]
I think this should be an easy one.

Can an ATTR_SET include an ATTR_SET? Currently, that
appears to be allowed. I've no idea if that's intended
or not. Maybe clarify? If allowed, would that complicate
the stack push/pop model in the text?

IANA understands that, upon approval of this document, there is a single
IANA Action that needs to be completed.

Under early registration procedures the value 128 was registered in the
BGP Path Attributes subregistry of the Border Gateway Protocol (BGP)
Parameters located at:

http://www.iana.org/assignments/bgp-parameters/bgp-parameters.xml#bgp-parameters-2

The reference for value 128 in this subregistry should be changed to [
RFC-to-be ] and the TEMPORARY registration indicators should be removed.

IANA understands that this is the only action required upon approval of
this document.

State changed to In Last Call from Last Call Requested.

The following Last Call Announcement was sent out:

From: The IESG
To: IETF-Announce
CC:
Reply-To: ietf@ietf.org
Subject: Last Call:  (Internal BGP as Provider/Customer Edge Protocol for BGP/MPLS IP Virtual Private Networks (VPNs)) to Proposed Standard


The IESG has received a request from the Layer 3 Virtual Private Networks
WG (l3vpn) to consider the following document:
- 'Internal BGP as Provider/Customer Edge Protocol for BGP/MPLS IP
  Virtual Private Networks (VPNs)'
  as a 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 2011-05-30. 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


  This document defines protocol extensions and procedures for BGP
  Provider/Customer edge router iteration in BGP/MPLS IP VPN [RFC4364]
  networks.  These have the objective of making the usage of the BGP/
  MPLS IP VPN transparent to the customer network, as far as routing
  information is concerned.




The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-l3vpn-ibgp/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-l3vpn-ibgp/

No IPR disclosures have been submitted directly on draft-ietf-l3vpn-ibgp,
but there are disclosures on a related document. Search result on
draft-marques-l3vpn-ibgp, "Internal BGP as PE-CE protocol", that
was replaced by draft-ietf-l3vpn-ibgp, "Internal BGP as Provider/Customer
Edge Protocol for BGP/MPLS IP Virtual Private Networks (VPNs)"

ID # 1146 "Juniper's Statement of IPR related to draft-marques-l3vpn-ibgp-01"

(1.a) Who is the Document Shepherd for this document? Has the
Document Shepherd personally reviewed this version of the
document and, in particular, does he or she believe this
version is ready for forwarding to the IESG for publication?

Ben Niven-Jenkins is the Document Shepherd for draft-ietf-l3vpn-ibgp. I have personally reviewed the -07 version of the document and believe that this version is ready for forwarding to the IESG for publication as a Standards Track RFC.

(1.b) Has the document had adequate review both from key WG members
and from key non-WG members? Does the Document Shepherd have
any concerns about the depth or breadth of the reviews that
have been performed?

The document was jointly WG Last Called in the L3VPN and IDR WGs which led to some small changes to the specification.

No outstanding comments exist and it is my opinion that the document has received sufficient review and is now ready to be published.

(1.c) Does the Document Shepherd have concerns that the document
needs more review from a particular or broader perspective,
e.g., security, operational complexity, someone familiar with
AAA, internationalization or XML?

No

(1.d) Does the Document Shepherd have any specific concerns or
issues 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. Has an IPR disclosure related to this document
been filed? If so, please include a reference to the
disclosure and summarize the WG discussion and conclusion on
this issue.

No concerns and no IPR disclosures have been filed.

(1.e) 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 were no objections during the joint L3VPN and IDR WG Last Calls on the document.

(1.f) 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
entered into the ID Tracker.)

No, not to my knowledge.

(1.g) Has the Document Shepherd personally verified that the
document satisfies all ID nits? (See the Internet-Drafts Checklist
and http://tools.ietf.org/tools/idnits/). Boilerplate checks are
not enough; this check needs to be thorough. Has the document
met all formal review criteria it needs to, such as the MIB
Doctor, media type and URI type reviews?

The draft passes the idnits tools with one error that a single line is greater than 72 characters.

Instead of submitting a new version with just that edit it is my opinion that it can either be tackled at the same time as any IETF LC comments or fixed by the RFC Editor prior to publication.

There are no MIB or other elements in the document that would warrant review. As such, I have no concerns here.

(1.h) Has the document split its references into normative and
informative? 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
strategy for their completion? Are there normative references
that are downward references, as described in [RFC3967]? If
so, list these downward references to support the Area
Director in the Last Call procedure for them [RFC3967].

The document splits it references into normative and informative. All normative references are to published RFCs. There are no downward references.


(1.i) Has the Document Shepherd verified that the document IANA
consideration section exists and is consistent with the body
of the document? If the document specifies protocol
extensions, are reservations requested in appropriate IANA
registries? Are the IANA registries clearly identified? If
the document creates a new registry, does it define the
proposed initial contents of the registry and an allocation
procedure for future registrations? Does it suggest a
reasonable name for the new registry? See [RFC5226]. If the
document describes an Expert Review process has Shepherd
conferred with the Responsible Area Director so that the IESG
can appoint the needed Expert during the IESG Evaluation?

The document contains an IANA Considerations section and requests a code point in the BGP Path Attributes registry. An early allocation of the requested code point has already been assigned by IANA.

(1.j) Has the Document Shepherd verified that sections of the
document that are written in a formal language, such as XML
code, BNF rules, MIB definitions, etc., validate correctly in
an automated checker?

No section of this document is written in a formal language.

(1.k) 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
Relevant content can frequently be found in the abstract
and/or introduction of the document. If not, this may be
an indication that there are deficiencies in the abstract
or introduction.

In current RFC4364 deployments, when BGP is used as the PE-CE routing protocol, BGP peering sessions are typically configured as an external peering between the VPN provider AS and the customer network AS.

While this technique works well in situations where there are no BGP routing exchanges between the client network and other networks, it does have drawbacks for customer networks that use BGP internally for purposes other than interaction between CE and PE routers.

In order to make the usage of BGP/MPLS VPN services as transparent as possible to any external interaction, it is desirable to define a mechanism by which PE-CE routers can exchange BGP routes by means other than external BGP.

This document specifies a means to use Internal BGP for the purpose of exchanging PE-CE routes.


Working Group Summary
Was there anything in WG process that is worth noting? For
example, was there controversy about particular points or
were there decisions where the consensus was particularly
rough?

This document is a product of L3VPN WG. The document underwent WG Last Call in both the L3VPN and IDR WGs.

Document Quality
Are there existing implementations of the protocol?

I am aware of two existing implementations.

Have a significant number of vendors indicated their plan
to implement the specification?

I do not know. However there are already two implementations that I am aware of.

Are there any reviewers that merit special mention as
having done a thorough review, e.g., one that resulted in
important changes or a conclusion that the document had no
substantive issues?

Not to the best of my knowledge.

If there was a MIB Doctor, Media Type or other expert
review, what was its course (briefly)? In the case of a
Media Type review, on what date was the request posted?

No such review was conducted as it was not considered necessary.