Label Switched Path (LSP) Ping for Pseudowire Forwarding Equivalence Classes (FECs) Advertised over IPv6
draft-ietf-mpls-ipv6-pw-lsp-ping-04

[Ballot comment]
When I see the long list of RFC EDITOR notes for an 8 pages document... I won't spend my time trying reinsert the notes in order to read a clean document. Bottom line: I will trust the other ADs on this one.

[Ballot discuss]
I am updating my discuss based on a review by Matthew Bocci on behalf of the RTG Dir and PWE3 Chairs.

The points that Matthew makes account for my confusion that lead to the original discuss.

There has been discussion between the Review and on of the authors and there is a simple way forward on each of the points below.


1) Title: The title of the draft is "Label Switched Path (LSP) Ping for IPv6
Pseudowire FECs". This is confusing as it suggests that there are
special PW FECs for IPv6. In fact, PW FECs are agnostic to the underlying
IP version. Therefore, I suggest changing this to something like "Label
Switched Path (LSP) Ping for Pseudowire FECs Advertised over IPv6".

2) Abstract, 1st paragraph: The abstract (and only the abstract) refers to PW
LSPs, but this is not common terminology in existing RFCs. It is true that
each direction of an MPLS PW is comprised of a unidirectional LSP, but it
would be better to try to align more closely with common terminology and
call them the LSPs used for each direction of an MPLS PW.

3) Abstract, 2nd paragraph: The draft refers to an IPv6 PW. However, this
term could be confused with the colloquial term for an IP Layer 2
transport PW, which is a specific PW type that can carry IPv4 or IPv6. I
suggest replacing this term with 'a PW that is setup and maintained using
an IPv6 LDP session.' Likewise, the short version of the draft title in
the draft headers could be clarified to something like 'PW LSP Ping for
IPv6'.

4) Introduction: there are a few places where the text refers to a 'target
LDP session'. It isn't clear if this means the src/dst of the LDP session
that an LSP ping echo request message is targeting (hence target is ok) or
if it really means the 'targeted LDP session', which is what this type of
LDP session is normally referred as. Please clarify.

5) Figure 1 and Figure 2 titles. These are not new FEC types for IPv4 and
IPv6, but rather new target FEC stack sub-TLVs. I would help readability
to modify the titles accordingly.

[Ballot comment]
Just two editorial nits (with a whine to the IESG about one of them):

In the abstract:

  This document extends the PW LSP Ping and traceroute mechanisms so
  they can be used with IPv6 PWs, and updates RFC 4379.

That doesn't make sense to me. If the reason that this document updates 4379 is because it extends the ping and traceroute mechanisms, then you should just say that:

  This document updates and extends RFC 4379 so that the PW LSP Ping
  and traceroute mechanisms can be used with IPv6 PWs.

or simply strike the clause ", and updates RFC 4379", since it's unnecessary. If that's not what you meant, you had better explain what in 4379 got updated. But I think the suggested fix is probably what you meant.

[Grump to IESG: This is why the nits rule is stupid. I am guessing that the abstract originally said "This document extends the PW LSP Ping and traceroute mechanisms so they can be used with IPv6 PWs", somebody told these authors that abstract *had to* state that it updates 4379, and the authors dutifully put in the useless final clause. This is a waste of text and furthers the idea that this is a rule that must be followed even if the text is meaningless. It isn't a rule and I find adding this in is now just another writing tic by draft authors.]

Section 3.1:

    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |            PW Type            |          Must Be Zero        |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Instead of "Must Be Zero", can you label this "zero padding" as you do in section 3.2? "Must Be Zero" looks like it is a field with semantics that must be set to zero, whereas I think this is just padding.

[Ballot discuss]
This is a pseudowire document and it is a great pity that it was not taken through the pseudowire WG so that it would be listed in their document set and thus be more visible to readers looking for PW related documents. I am not sure whether it is possible to get this to show on with their doc set but it would be useful if it could.

As far as I am able to determin, this document was not formally reviewed by the PWE3 WG, one purpose of this discuss is thus to make sure that this has been adequately reviewed by people with PW expertise.

My second concern is whether FEC128 data structures should be defined in this draft, or whether this draft should be used as an opportunity to retire FEC128, in which case the FEC 128 IPv6 definition should be removed from the draft. This is a discussion that should take place in the PWE3 WG.

[Ballot discuss]
This is a pseudowire document and it is a great pity that it was not taken through the pseudowire WG so that it would be listed in their document set and thus be more visible to readers looking for PW related documents. I am not sure whether it is possible to get this to show on with their doc set but it would be useful if it could.

As far as I am able to determin, this document was not reviewed by the PWE3 WG, thus the main purpose of this discuss is to make sure that this has been adequately reviewed by people with PW expertise.

IANA has reviewed draft-ietf-mpls-ipv6-pw-lsp-ping-03 and has the following comments:

IANA understands that, upon approval of this document, there are two IANA
actions which must be completed.

First IANA in the TLVs and sub-TLVs subregistry of the Multi-Protocol Label
Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters registry located at:

http://www.iana.org/assignments/mpls-lsp-ping-parameters/mpls-lsp-ping-parameters.xml

The following existing registrations will be changed as follows:

Type Sub-Type Value Field Reference
---- -------- -------------------------------------- -------------
1 9 IPv4 "FEC 128" Pseudowire (Deprecated) [ RFC-to-be ]
1 10 IPv4 "FEC 128" Pseudowire [ RFC-to-be ]
1 11 IPv4 "FEC 129" Pseudowire [ RFC-to-be ]

Also, in the same subregistry, the following registrations will be changed
as follows:

Type Sub-Type Value Field Reference
---- -------- -------------------------------------- -------------
21 9 IPv4 "FEC 128" Pseudowire (Deprecated) [ RFC-to-be ]
21 10 IPv4 "FEC 128" Pseudowire [ RFC-to-be ]
21 11 IPv4 "FEC 129" Pseudowire [ RFC-to-be ]

Second, also in the TLVs and sub-TLVs subregistry of the Multi-Protocol Label
Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters registry located at:

http://www.iana.org/assignments/mpls-lsp-ping-parameters/mpls-lsp-ping-parameters.xml

The following existing registrations will be added as follows:

Type Sub-Type Value Field Reference
---- -------- ------------------------- --------------
1 [ TBD1 ] IPv6 "FEC 128" Pseudowire [ RFC-to-be ]
1 [ TBD2 ] IPv6 "FEC 129" Pseudowire [ RFC-to-be ]

IANA understands that these two actions are the only ones required upon
approval of this document.

Note: The actions requested in this document will not be completed
until the document has been approved for publication as an RFC.

The following Last Call announcement was sent out:

From: The IESG
To: IETF-Announce
CC:
Reply-To: ietf@ietf.org
Subject: Last Call:  (Label Switched Path (LSP) Ping for IPv6 Pseudowire FECs) to Proposed Standard


The IESG has received a request from the Multiprotocol Label Switching WG
(mpls) to consider the following document:
- 'Label Switched Path (LSP) Ping for IPv6 Pseudowire FECs'
  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 2012-11-09. 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

  Multi-Protocol Label Switching (MPLS) Label Switched Path (LSP) Ping
  and traceroute mechanisms are commonly used to detect and isolate
  data plane failures in all MPLS LSPs including Pseudowire (PW) LSPs.
  The PW LSP Ping and traceroute elements, however, are not specified
  for IPv6 address usage.

  This document extends the PW LSP Ping and traceroute mechanisms so
  they can be used with IPv6 PWs, and updates RFC 4379.


The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-mpls-ipv6-pw-lsp-ping/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-mpls-ipv6-pw-lsp-ping/ballot/


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

AD review...

Thanks for this document. I have done my usual AD review and have
nothing to add except for some minor comments on the IANA section.
If you could make an update that would be very helpful.

You do not need to wait for the submission gates to reopen on 5th
November. If you send me the file(s) for submission I will get the
Secretariat to post them.

Thanks,
Adrian

---

Section 6

It appears you are asking to *replace* the pointer to RFC 4379 for the
three IPv4 sub-TLVs. I don't think you should do that because they are
defined in 4379. So add the word "also".

OLD
  Update the names of the Value fields of these three Sub-TLVs, adding
  the "IPv4" qualifier (see Section 2), and update the Reference to
  point to this document:
NEW
  Update the names of the Value fields of these three Sub-TLVs, adding
  the "IPv4" qualifier (see Section 2), and update the Reference to
  also point to this document:
END

---

Section 6 usefully calls out TBD1 and TBD2, but the rest of the document
uniformly uses TBD. If you could update to always use TBD1 and TBD2 this
will ensure that the RFC Editor works with IANA to get this right.

---

In Section 6, please explicitly ask IANA to make the appropriate entries
in the Type 21 sub-TLVs list.

(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?


  The MPLS working group request that:

        Label Switched Path (LSP) Ping for IPv6 Pseudowire FECs

                draft-ietf-mpls-ipv6-pw-lsp-ping-02

  is published as an RFC on the standards track.


This draft specific a rather small extension to RFC4379 (Detecting
Multi-Protocol Label Switched (MPLS) Data Plane Failures), it adds
elements necessary to use LSP Ping for IPv6 PWs. This protocol
specification is intended for service  provider networks to be useed
under operational conditions, it clearly meets the criteria to become
a standards track document.


(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:


Multi-Protocol Label Switching (MPLS) Label Switched Path (LSP) Ping
and traceroute mechanisms are commonly used to detect and isolate
data plane failures in all MPLS LSPs including Pseudowire (PW) LSPs.
The PW LSP Ping and traceroute elements, however, are not specified
for IPv6 address usage.

This document extends the PW LSP Ping and traceroute mechanisms so
they can be used with IPv6 PWs, and updates RFC 4379.



    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?

There is a general agreement in the working group that some of our
protocols need to be extended to meet requirements present in IPv6
networks. This is one of such extension to LSP Ping.

There is good support for the document.

    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?

We know of several implementations or intents to implement this
draft.

    Personnel:

    Who is the Document Shepherd?

Loa Andersson is the document shepherd.

    Who is the Responsible Area Director?

Adrian Farrel 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 reviewed the document at the point in time
when it was being polled to become a working group document and as
a part of the preparation for the working group last call.
The IANA section has been reviewed several times.

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

No such concerns.

    (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.

The document shepherd believes that the current review situation is
sufficient.

    (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 such concerns.

    (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?

A poll for IPRs has been done among the authors and in the working
group.
All the authors has confirmed that they are not aware of any existing
IPR claims.

    (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 disclosures have been submitted directly on draft-ietf-mpls-
ipv6-pw-lsp-ping or its predecessor draft-chen-mpls-ipv6-pw-lsp-ping.

    (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?

There are good support for this document!

    (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 such threats!

    (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.

This document passes the ID-nits tool clean.

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

No such formal review requirements!

    (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?

All normative references are RFCs.

    (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 references.

    (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.

This document extends and updates RFC4379, this is discussed in the
Abstract and the Introduction

    (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).

This document has a clear and well-written IANA section.



    (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 new IANA registries.

    (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.

No such review required.