Clarification of Segment ID Sub-TLV Length for RFC 8287
draft-ietf-mpls-rfc8287-len-clarification-04

[Ballot comment]
Please use the BCP 14 boilerplate from RFC 8174 (the current Section 2
seems to be using the RFC 2119 text, without accounting for errata, and
an extra RFC 8174 reference appended at the end).

[Ballot discuss]
This should be very easy to clear up

* Section 4.3

Since this whole draft is about clarifying Sub-TLV length calculations I think this section needs to cover the length calculation for the unnumbered Adjacency Type (Adj. Type 0 in RFC8287).

[Ballot discuss]
The Gen-ART reviewer caught this error which seems important to fix:

Figure of Section 4.2: Type = 35 (IPv4 IGP-Prefix SID) ---> Type = 35 (IPv6 IGP-Prefix SID)

[Ballot comment]
** Section 4, per “The figures in section 5.1, 5.2 and 5.3 of [RFC8287] are replaced by the below figures in section 4.1, 4.2 and 4.3 respectively”:

--  none of the diagram in Section 4.1, 4.2 or 4.3 are explicitly labeled as figures

-- section 4.3 contains two “figures” (one is called a table in the text and the other has no designation).  Which one of these is supposed to be a replacement for RFC8287 Section 5.3?

** Section 4.3.  Assuming that the second figure is the replacement for RFC8287’s Section 5.3 figure, the length is still confusing to me.  The figure in this draft appears to be a specific instance of the populated Sub-TLV.  The existing figure in RFC8287 appears to be a generic depiction.  The new figure doesn’t appear to be relevant (or presented incorrect information) if Adj Type = 1 and Protocol = 1 (for example).

** Section 4.3.  Typo.  s/Protocol =0/Protocol = 0/

** Section 6. Recommend clarifying that there are no additional security considerations (not that there aren’t any).  s/This document updates [RFC8287] and does not introduce any security considerations/This document updates [RFC8287] and does not introduce any additional security considerations/

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

The IANA Functions Operator has completed its review of draft-ietf-mpls-rfc8287-len-clarification-02. If any part of this review is inaccurate, please let us know.

The IANA Functions Operator has a question about one of the actions requested in the IANA Considerations section of this document.

The IANA Functions Operator understands that, upon approval of this document, there are no IANA Actions that need completion. The IANA Functions Operator requests that the IANA Considerations section of the document remain in place upon publication.

IANA Question --> IANA understands that this document updates and clarifies RFC8287. Should any reference in the Adjacency Type in the IGP-Adjacency Segment ID registry on the Multiprotocol Label Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters registry page located at:

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

be modified to reflect [ RFC-to-be ]? Are there any other references in other registries that should be modified or updated?

Thank you,

Sabrina Tanamal
Senior IANA Services Specialist

The following Last Call announcement was sent out (ends 2019-07-31):

From: The IESG
To: IETF-Announce
CC: mpls@ietf.org, db3546@att.com, draft-ietf-mpls-rfc8287-len-clarification@ietf.org, mpls-chairs@ietf.org, Loa Andersson , loa@pi.nu
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (RFC8287 Sub-TLV Length Clarification) to Proposed Standard


The IESG has received a request from the Multiprotocol Label Switching WG
(mpls) to consider the following document: - 'RFC8287 Sub-TLV Length
Clarification'
  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 2019-07-31. 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


  RFC8287 defines the extensions to MPLS LSP Ping and Traceroute for
  Segment Routing IGP-Prefix and IGP-Adjacency Segment Identifier
  (SIDs) with an MPLS data plane.  RFC8287 proposes 3 Target FEC Stack
  Sub-TLVs.  While the standard defines the format and procedure to
  handle those Sub-TLVs, it does not sufficiently clarify how the
  length of the Segment ID Sub-TLVs should be computed to include in
  the Length field of the Sub-TLVs which may result in interoperability
  issues.

  This document updates RFC8287 by clarifying the length of each
  Segment ID Sub-TLVs defined in RFC8287.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-mpls-rfc8287-len-clarification/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-mpls-rfc8287-len-clarification/ballot/


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

The MPLS working group requests that

          draft-ietf-mpls-rfc8287-len-clarification-01

Is published as a Proposed Standard.

(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?

  We request that the document is published as a Proposed Standard,
  the title page says Standards Track.

  PS is the right type of RFC as the sole purpose of the document is
  to update an existing Standards Track RFC, RFC 8287.

(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

  RFC8287 defines the extensions to MPLS LSP Ping and Traceroute for
  Segment Routing IGP-Prefix and IGP-Adjacency Segment Identifier
  (SIDs) with an MPLS data plane. RFC 8287 proposes 3 Target FEC
  Stack Sub-TLVs. While the standard defines the format and procedure
  to handle those Sub-TLVs, it does not sufficiently clarify how
  the length of the Segment ID Sub-TLVs should be computed to include
  in the Length field of the Sub-TLVs which may result in
  interoperability issues.

Working Group Summary

  There were no controversies progressing this document, the support
  in the working group is solid.

Document Quality

  In this case the question of existing implementations is a bit
  tricky, the document is a clarification to RFC 8287, of which there
  are implementations. The problem with the Segment ID Sub-TLV was
  discovered when preparing inter-op test of RFC 8287.

Personnel

  Document Shepherd: Loa ANdersson
  Responsible Area Director: Deborah Brungard

(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 this document when the Individual
  draft was first posted, when the working group adoption poll was
  issued and at wglc.

(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.

  No such reviews are necessary.

(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.

  All the authors and contributors has stated on the MPLS WG mailing
  list that they are unaware of any undisclosed IPRs.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

  There are no IPRs disclosed against this document.

(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?

  The support for the document is very strong.

(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

  The document passes nits-tool clean, no other nits found.

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

  No such reviewa required.

(13) Have all references within this document been identified as
either normative or informative?

  This document has only normative regerences. It is the shepherds
  opinion that no Informative references are required.

(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 regerences are to documents on the standrds track or to
  BCP (BCP 14).

(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.

  Publicaton of this document will update RFC 8287, this is mentioned
  in the Abstract and discussed in 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 does not request any IANA actions.

(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 such 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 reviewa required.

The MPLS working group requests that

          draft-ietf-mpls-rfc8287-len-clarification-01

Is published as a Proposed Standard.

(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?

  We request that the document is published as a Proposed Standard,
  the title page says Standards Track.

  PS is the right type of RFC as the sole purpose of the document is
  to update an existing Standards Track RFC, RFC 8287.

(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

  RFC8287 defines the extensions to MPLS LSP Ping and Traceroute for
  Segment Routing IGP-Prefix and IGP-Adjacency Segment Identifier
  (SIDs) with an MPLS data plane. RFC 8287 proposes 3 Target FEC
  Stack Sub-TLVs. While the standard defines the format and procedure
  to handle those Sub-TLVs, it does not sufficiently clarify how
  the length of the Segment ID Sub-TLVs should be computed to include
  in the Length field of the Sub-TLVs which may result in
  interoperability issues.

Working Group Summary

  There were no controversies progressing this document, the support
  in the working group is solid.

Document Quality

  In this case the question of existing implementations is a bit
  tricky, the document is a clarification to RFC 8287, of which there
  are implementations. The problem with the Segment ID Sub-TLV was
  discovered when preparing inter-op test of RFC 8287.

Personnel

  Document Shepherd: Loa ANdersson
  Responsible Area Director: Deborah Brungard

(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 this document when the Individual
  draft was first posted, when the working group adoption poll was
  issued and at wglc.

(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.

  No such reviews are necessary.

(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.

  All the authors and contributors has stated on the MPLS WG mailing
  list that they are unaware of any undisclosed IPRs.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

  There are no IPRs disclosed against this document.

(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?

  The support for the document is very strong.

(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

  The document passes nits-tool clean, no other nits found.

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

  No such reviewa required.

(13) Have all references within this document been identified as
either normative or informative?

  This document has only normative regerences. It is the shepherds
  opinion that no Informative references are required.

(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 regerences are to documents on the standrds track or to
  BCP (BCP 14).

(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.

  Publicaton of this document will update RFC 8287, this is mentioned
  in the Abstract and discussed in 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 does not request any IANA actions.

(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 such 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 reviewa required.