Subject: Please publish draft-ietf-ccamp-isis-interas-te-extension-02.txt

From: "Adrian Farrel" <[email-masked]>
Date: Mon, 14 Apr 2008 11:57:10 +0100

Proto-write-up for draft-ietf-ccamp-isis-interas-te-extension-02.txt

Intended status : Standards Track

This draft may be considered in parallel with draft-ietf-ccamp-ospf-
interas-te-extension-05.txt, but it is *not* required to process the
I-Ds in parallel.

> (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 CCAMP and in the
ISIS working group. In particular, it received considerable input from
IS-IS experts in its early stages.

Document Shepherd believes reviews to have been adequate.

> (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.

> (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.

> (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?

IANA section checked.

> (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.
                     
Traffic engineering extensions to IS-IS have been defined and are used
in support of MPLS-TE and GMPLS. The extensions provide a way of
encoding the TE information for TE-enabled links within the network and
flooding this information within an IS-IS area.

When establishing inter-AS MPLS-TE or GMPLS Label Switched Paths (LSPs)
a path is computed one AS at a time. This path may be computed using
conventional techniques at the first ASBR of each AS, or by using
Path Computation Elements (PCEs) as specified by the PCE working group.
In either case, if two ASes are connected by more than one inter-AS TE
link, it is helpful for the computation point to know the capabilities
of the available TE links in order to select a suitable path.

This document describes extensions to IS-IS to flood TE information
about inter-AS links. A new IS-IS top-level TLV is defined for this 
purpose in order to support transparent backward compatibility and to
support the potential use of separate IS-IS flooding instances.

This document does not propose or define any mechanisms to advertise
any other extra-AS TE information. This means that there is no proposal
to distribute TE information from one AS within another AS. Nor is there
any mechanism proposed to define or distribute "TE reachability" 
information.

>        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.

Two points arose during working group discussions that are worth 
noting. Both points were resolved satisfactorily.

1. Separate IS-IS Instances
The original proposal in this I-D used extensions to the existing IS-IS
top-level TLV used for TE information distribution. This has been 
changed after requests from the ISIS working group to use a different
top-level TLV enabling easier backward compatibility and more flexible 
transition to multi-instance IS-IS in the future.

2. No Change to Scaling/Flooding Paradigm
Many people within CCAMP expressed a concern that the I-D might indicate
the intention to distribute TE information from one AS into another AS.
This would obviously break the as-based scaling and confidentiality 
paradigms of IGP routing. The authors were very clear that this was not
the intention and have added a specific section to cover non-objectives.

>        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 a known implementation of the extensions. There was also
good support for the work from other vendors with the same objectives.

Document review by the IS-IS working group deserves special mention for
its care and thoroughness.