A Backward-Recursive PCE-Based Computation (BRPC) Procedure to Compute Shortest Constrained Inter-Domain Traffic Engineering Label Switched Paths
draft-ietf-pce-brpc-09

IANA review comments:

Action #1

Upon approval of this document, the IANA will make the following
assignments in the "Path Computation Element Protocol" registry at
http://www.iana.org/assignments/TBD-PCEP
sub-registry "Request Parameters Bit Flags"

Bit | Name | Description | Reference
-------+--------+-------------------+-------
7 | VSPT | VSPT flag | [RFC-pce-brpc-09]


Action #2

Upon approval of this document, the IANA will make the following
sssignments in the "Path Computation Element Protocol" registry at
http://www.iana.org/assignments/TBD-PCEP
sub-registry "Error Types and Values"

Error Type | Meaning | Reference
--------+---------------------------------------+----------
13 | BRPC procedure completion failure | [RFC-pce-brpc-09]
| Error-value |
| 1: BRPC procedure not supported by | [RFC-pce-brpc-09]
| one a PCE along the domain path |


Action #3

Upon approval of this document, the IANA will make the following
assignments in the "Path Computation Element Protocol" registry at
http://www.iana.org/assignments/TBD-PCEP
sub-registry "No-Path Flags"

Bit | Name | Description | Reference
--------+-------+--------------------------------+----------
4 | BRPC | BRPC Path Computation chain unavailable | [RFC-pce-brpc-09]

We understand the above to be the only IANA Actions for this
document.

Proto-write-up for draft-ietf-pce-brpc-08.txt

Intended status : Standards Track

> (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?

Adrian Farrel is the document shepherd.
He has personally reviewed the I-D and believes it is ready for
forwarding to the IESG for publication.

> (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?

I-D has had a good level of discussions and review in the PCE working
group. It has not had review in any wider forums, but none was deemed
necessary or appropriate.

> (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 concerns.

> (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.

The document is sound.

An IPR disclosure can be found at https://datatracker.ietf.org/ipr/917/

This disclosure was made "somewhat late" in the process. The I-D was at
working group revision 06, but one of the I-D authors was also an author
of the IPR filing.

An apology was made to the working group for the late disclosure and the
working group was given the opportunity to discuss the issue and consider
whether to abandon the I-D and develop alternate mechanisms. However,
despite the fact that viable alternate mechanisms have been shown to be
possible, no-one in the working group expressed any concerns or desire
to make any changes.

> (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?

Consensus is good.
WG last call issues were limited to editorial and minor functional nits.

> (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 threats. No discontent.

> (1.g)  Has the Document Shepherd personally verified that the
>        document satisfies all ID nits?  (See
>        http://www.ietf.org/ID-Checklist.html 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?

All checks made.

> (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].

References split.
No downrefs.

> (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 [RFC2434].  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 defines small protocol enhancements to PCEP. The PCEP
specification is progressing through the IESG approval process and no
IANA registry has yet been created. Nevertheless, this I-D requests
further allocations from the PCEP registry that IANA will create and
manage.

The IANA section of this I-D uses the same language as the PCEP
specification and, in particular, uses the same sub-registry names.

Further, to help ensure consistent allocation of protocol codepoints, a
temporary (non-definitive) registry is maintained at
www.olddog.co.uk/pcep-codepoints.txt

> (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 such formal language is used.

> (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.

The ability to compute shortest constrained Traffic Engineering Label
Switched Paths (TE LSPs) in Multiprotocol Label Switching (MPLS) and
Generalized MPLS (GMPLS) networks across multiple domains (where a
domain is a collection of network elements within a common sphere of
address management or path computational responsibility such as an IGP
area or an Autonomous Systems) has been identified as a key requirement.

The Path Computation Element (PCE) architecture is defined in RFC4655. A
PCE is capable of computing paths within a domain, but cannot compute
paths that traverse other domains. This limitation is imposed for
scalability and confidentiality (i.e., confidentiality of topological
and operational parameters). However, PCEs may cooperate to derive
end-to-end inter-domain paths.

This document describes a PCE-based path computation procedure to
compute optimal inter-domain constrained MPLS TE and GMPLS LSPs. The
procedure relies on the use of multiple PCEs to compute such inter-
domain shortest constrained paths across a pre-determined sequence of
domains, using a backward recursive path computation technique.

>        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?

WG has good consensus with no disputes or disagreements.
An IPR disclosure has been filed, but the WG has decided to proceed with
this I-D.

>        Document Quality
>          Are there existing implementations of the protocol?  Have a
>          significant number of vendors indicated their plan to
>          implement the specification?  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?  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?

There is one known implementation of this document with several known
implementations in the pipe-line. Given how small the protocol
extensions defined in this document are, it is considered that
proceeding on the basis of one implementation is OK.