1. Does the working group (WG) consensus represent the strong concurrence of a
few individuals, with others being silent, or did it reach broad agreement?
During both the adoption call and the WGLC, this draft has gone through long
discussions. The majority of the WG agrees with solution.
WGLC: https://mailarchive.ietf.org/arch/msg/lsr/wumkQrT8CakzJr93M1p-AM3QzT8/
Adoption call:
https://mailarchive.ietf.org/arch/msg/lsr/V4r9wJuDA1Wl9wMEXRyX3MtQMxk/
2. Was there controversy about particular points, or were there decisions where
the consensus was particularly rough?
1)
There was a discussion about whether the configuration control should be
enforced, "SHOULD" vs. "MUST". email archive:
https://mailarchive.ietf.org/arch/msg/lsr/dTCbe0H8V9S_9sHyIhL_lxMzEsQ/
Suggestion from Bruno
(https://mailarchive.ietf.org/arch/msg/lsr/YBYQtO4XvnidSQ8DnwcS2C52F34/):
<snip> Section 7.1
"It is RECOMMENDED that implementations which support the sending of MP-TLVs
provide configuration controls to enable/disable generation of MP-TLVs. "
Possibly changing RECOMMENDED to REQUIRED
</snip>
To resolve this comment, the authors made the following text change in Version
-06:
v -05:
Implementations SHOULD report alarms under the following conditions:
v -06:
Implementations which support disablement of MP-TLVs MUST report
alarms under the following conditions:
And this is the email reply from Les:
https://mailarchive.ietf.org/arch/msg/lsr/leroGjztny0UdSoendvFj7YQkNM/
<snip>
In my mind there is a difference between defining what is necessary to
guarantee interoperability and defining what makes things easier to use (or -
if you prefer - easier to deploy). The former demands normative language – the
latter does not. But you seem to want them to be treated the same. I don’t
agree with this – not least because “easy to use” is a very subjective
criteria. People may legitimately have very different opinions on this.
That said, I took a look at RFC 7606 (thanx for the reference).
What that RFC does is discuss how to handle reception of protocol
advertisements which deviate from the expected content in some way – and it
does use MUST in requiring reporting of these anomalies. With that in mind, V6
of MP-TLV draft has been published with Section 7.1 modified to use MUST in
reporting alarms:
“Implementations which support disablement of MP-TLVs MUST report
alarms under the following conditions…”
We have not, however, modified the language in the previous paragraph i.e.,
RECOMMENDED is still used as regards implementing suggested knobs. This is
consistent with the point I made above regarding “ease of use”. </snip>
Considering there are implementations from multiple vendors that follow the
mechanism defined in this document without the explicit configuration, which
means a router may send MP-TLV without explicit enablement, changing from
"RECOMMNDED" to "REQUIRED" is not going to help with interoperability.
2)
Whether it's necessary to explicitly define keys for all TLVs that support
MP-TLV. There was suggestion of enumerating keys for all code points. However,
although the word "key" is introduced in this draft, the concept of a key in an
IS-IS TLV is not new. It's essential to correctly parse ISIS LSDB.
Ketan's email about specifying the "key":
https://mailarchive.ietf.org/arch/msg/lsr/SAdZH7D3Y7PTLxdLBT86-sIS87U/
The key of a TLV is implicitly defined:
https://mailarchive.ietf.org/arch/msg/lsr/pH7M4MBfg1FFKI4hsLlnqQ_dn60/https://mailarchive.ietf.org/arch/msg/lsr/6PbU-KcARoELuYrrdrs3OnYKn5U/https://mailarchive.ietf.org/arch/msg/lsr/8_m_WBo9NJ1jovWuYDTT8O-29xA/
Reply from Chris explain well this is how TLVs are parsed in ISIS today:
https://mailarchive.ietf.org/arch/msg/lsr/11c9Cg2AgF5zCRDTnSb35zQisvk/
Ketan's reply later in the thread clarifying why he's supporting the
publication of this draft after he went through some TLVs and convinced himself
that it's not necessary to specify all the keys:
https://mailarchive.ietf.org/arch/msg/lsr/U3ImXcT5yDgvFCb3VLa5t9C4As4/
So far people who think the key is under specified have not been able to
provide an example, where the definition of an existing TLV is not clear. The
working grouping is aware that there might be interoperability issue with the
proposal, and it's clearly articulated in the draft. Henk's email did a very
well summarization:
https://mailarchive.ietf.org/arch/msg/lsr/ph0bXIg7SXX4MNW1G0oKQOkrCG4/
3) IETF LC Summary & Conclusion:
Throughout the IETF Last Call, Aijun repeatedly raised the same issue, despite
it being addressed multiple times during both the Working Group Last Call
(WGLC) and IETF LC. He challenged every directorate review, but received no
support for his argument from the community, WG experts, or directorate
reviewers.
* Publication Request & IETF LC Timeline
Publication was requested on 2/10/25:
https://mailarchive.ietf.org/arch/msg/lsr/ud5_YmvjshH75KD6vlfIOt5Ibbk/ IETF
Last Call (LC) was issued on 2/11/25 and ran through 2/25/25:
https://mailarchive.ietf.org/arch/msg/lsr/ZwIM6WMSxCD_rK9AscMrh-iXZAs/
* Routing Directorate (RtgDir) Review
Mach Chen (RtgDir) reviewed the latest version and supported moving the
document forward:
https://mailarchive.ietf.org/arch/msg/lsr/b_n-bmCPn5mP3XNOI6BxDZl2E5k/ Aijun
Wang later claimed that the issue of "undefined key information" remained,
despite Mach confirming that his comments were resolved. Aijun received no
support from the community for this claim.
* Operations Directorate (OpsDir) Review
Aijun raised the same issue again with the OpsDir reviewer (Giuseppe Fioccola):
https://mailarchive.ietf.org/arch/msg/lsr/Fv7U9msEm9-sUrzOOm0iO7RoIVY/ Giuseppe
responded clearly that he did not see this as an issue:
https://mailarchive.ietf.org/arch/msg/lsr/enMwFsdMVrf5OKmD1tpJmRaM-Ww/ All
OpsDir comments were resolved:
https://mailarchive.ietf.org/arch/msg/lsr/vqys_yHDKB82BkIXvioEN0QW0nY/
* Repeated Concerns Raised During IETF LC
Aijun raised the same concern again:
https://mailarchive.ietf.org/arch/msg/lsr/gPal2AYQklSE-WqUrYJd0SeuweI/ Les
Ginsberg provided a detailed response:
https://mailarchive.ietf.org/arch/msg/lsr/vXF0iQunncuynpYAivR-J9gk0Po/https://mailarchive.ietf.org/arch/msg/lsr/dC90EMogM576isGtWFiglgi0Haw/
* Further Review & Additional Responses
Adrian Farrel conducted an additional RtgDir review:
https://mailarchive.ietf.org/arch/msg/lsr/xcvA31trLlzEv58ZEwHOZatzZFM/ Email
exchanges between Adrian and Les addressed all comments, with clarifications
added to the text. Aijun sent the same concern to Adrian, who responded with a
clear, detailed explanation with examples demonstrating why Aijun’s statement
was incorrect: (Aijun’s Email) -
https://mailarchive.ietf.org/arch/msg/lsr/T9xtkFS84LrgWcOh1nx_GJtS9ic/
(Adrian’s Detailed Response) (Highly recommended for understanding TLV parsing
in IS-IS) -
https://mailarchive.ietf.org/arch/msg/lsr/nArqDW_dh7KUV7QTO57SLGPn-BY/ Joel
Halpern also supported Adrian’s response:
https://mailarchive.ietf.org/arch/msg/lsr/7Xb1_8tfaG0pyqldWAbZHt1AIOE/ Despite
these responses, Aijun continued to insist that his question was unanswered:
https://mailarchive.ietf.org/arch/msg/lsr/o5aSnMPOpSm_i2WYss8ISbbQ_y0/
* Security Directorate (SecDir) Review
David Mandelberg conducted the SecDir LC review:
https://mailarchive.ietf.org/arch/msg/lsr/z_eZLksvKvwZIuJROotAcK7fNR4/ Aijun
contacted David, asking to block the document’s progress:
https://mailarchive.ietf.org/arch/msg/lsr/nvFrXRZ0OukexdyZE6q7WweIVi8/ David
did not respond, and no further concerns were raised from SecDir.
4)
Aijun submitted a new draft with the same argument trying to stop the progress
of draft-ietf-lsr-multi-tlv:
https://mailarchive.ietf.org/arch/msg/lsr/fowS2U5NEYx_7m8xW5gtvPxnLmI/ Acee
Lindem's response as WG chair:
https://mailarchive.ietf.org/arch/msg/lsr/4VqiVl1H72ErMACCNbeCKpW8nnw/ It
clearly stated that the WG had reached consensus and we were not going to spend
more time discuss these "challenges". John Drake's response supporting the WG
consensus:
https://mailarchive.ietf.org/arch/msg/lsr/JQZurX3dgR0fNsDHXjRat3J38Y4/
3. Has anyone threatened an appeal or otherwise indicated extreme discontent? If
so, please summarize 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.)
Yes. Aijun Wang appealed on November 6, 2024:
https://mailarchive.ietf.org/arch/msg/lsr/r8_cD6VFK0AJnY-VMvFUVcsmKrw/https://mailarchive.ietf.org/arch/msg/lsr/chsd1CLQ9lvvWtz3Zi50pPeTUDU/https://mailarchive.ietf.org/arch/msg/lsr/dgvlgNDei9-kCfawrnQm1JDXUWU/
The IESG had reviewed the working group's processing of the document and found
that the records didn't support the claimed defects. Hence the appeal was
denied. Here is a link to Roman's appeal response email:
https://mailarchive.ietf.org/arch/msg/lsr/DbgM2i0AVLeeQsU2AtrDUzgEdww/
Before the formal appeal, Aijun raised the issue to the responsible AD and it
was closed by the AD:
https://mailarchive.ietf.org/arch/msg/lsr/PbYIOaF_Jo3lWaOKEn8x8ILxhrA/
4. For protocol documents, are there existing implementations of the contents of
the document? Have a significant number of potential implementers indicated
plans to implement? Are any existing implementations reported somewhere,
either in the document itself (as [RFC 7942][3] recommends) or elsewhere
(where)?
Yes, multi vendors. There are implementations that already follow the mechanism
defined in this document for some existing TLVs. To date, no one has
implemented the configuration option referenced in #2.
## Additional Reviews
5. Do the contents of this document closely interact with technologies in other
IETF working groups or external organizations, and would it therefore benefit
from their review? Have those reviews occurred? If yes, describe which
reviews took place.
N/A
6. Describe how the document meets any required formal expert review criteria,
such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.
A Routing Directorate and OPS directorate review have been requested.
7. If the document contains a YANG module, has the final version of the module
been checked with any of the [recommended validation tools][4] for syntax and
formatting validation? If there are any resulting errors or warnings, what is
the justification for not fixing them at this time? Does the YANG module
comply with the Network Management Datastore Architecture (NMDA) as specified
in [RFC 8342][5]?
N/A
8. Describe reviews and automated checks performed to validate sections of the
final version of the document written in a formal language, such as XML code,
BNF rules, MIB definitions, CBOR's CDDL, etc.
N/A
## Document Shepherd Checks
9. Based on the shepherd's review of the document, is it their opinion that this
document is needed, clearly written, complete, correctly designed, and ready
to be handed off to the responsible Area Director?
Yes - I've reviewed the document multiple times.
10. Several IETF Areas have assembled [lists of common issues that their
reviewers encounter][6]. For which areas have such issues been identified
and addressed? For which does this still need to happen in subsequent
reviews?
N/A
11. What type of RFC publication is being requested on the IETF stream ([Best
Current Practice][12], [Proposed Standard, Internet Standard][13],
[Informational, Experimental or Historic][14])? Why is this the proper type
of RFC? Do all Datatracker state attributes correctly reflect this intent?
The IETF stream is Proposed Standard. This is correct for a document that
codifies the common mechanism of extending the TLV content space through
multiple TLVs and the Datatracker reflects this.
12. Have reasonable efforts been made to remind all authors of the intellectual
property rights (IPR) disclosure obligations described in [BCP 79][7]? To
the best of your knowledge, have all required disclosures been filed? If
not, explain why. If yes, summarize any relevant discussion, including links
to publicly-available messages when applicable.
Yes. An IPR call was answered by all authors and contributors during the WGLC.
13. Has each author, editor, and contributor shown their willingness to be
listed as such? If the total number of authors and editors on the front page
is greater than five, please provide a justification.
The author list had been reduced to five authors and they all have contributed
to the document.
14. Document any remaining I-D nits in this document. Simply running the [idnits
tool][8] is not enough; please review the ["Content Guidelines" on
authors.ietf.org][15]. (Also note that the current idnits tool generates
some incorrect warnings; a rewrite is underway.)
All the document nits have been addressed.
15. Should any informative references be normative or vice-versa? See the [IESG
Statement on Normative and Informative References][16]
No.
16. List any normative references that are not freely available to anyone. Did
the community have sufficient access to review any such normative
references?
N/A
17. Are there any normative downward references (see [RFC 3967][9] and [BCP
97][10]) that are not already listed in the [DOWNREF registry][17]? If so,
list them.
No
18. Are there normative references to documents that are not ready to be
submitted to the IESG for publication or are otherwise in an unclear state?
If so, what is the plan for their completion?
No
19. Will publication of this document change the status of any existing RFCs? If
so, does the Datatracker metadata correctly reflect this and are those RFCs
listed on the title page, in the abstract, and discussed in the
introduction? If not, explain why and point to the part of the document
where the relationship of this document to these other RFCs is discussed.
No.
20. 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 aspects of the document requiring IANA assignments are
associated with the appropriate reservations in IANA registries. Confirm
that any referenced IANA registries have been clearly identified. Confirm
that each newly created IANA registry specifies its initial contents,
allocations procedures, and a reasonable name (see [RFC 8126][11]).
The IANA section and new code points have been reviewed.
This document requests IANA to add a column to a number of "IS-IS TLV
Codepoints" registries and a code point from IS-IS Sub-TLVs for IS-IS Router
Capability TLV.
21. List any new IANA registries that require Designated Expert Review for
future allocations. Are the instructions to the Designated Expert clear?
Please include suggestions of designated experts, if appropriate.
A new column is added to a number of existing registries.
All registries already have designated experts assigned.
[1]: https://www.ietf.org/about/groups/iesg/
[2]: https://www.rfc-editor.org/rfc/rfc4858.html
[3]: https://www.rfc-editor.org/rfc/rfc7942.html
[4]: https://wiki.ietf.org/group/ops/yang-review-tools
[5]: https://www.rfc-editor.org/rfc/rfc8342.html
[6]: https://wiki.ietf.org/group/iesg/ExpertTopics
[7]: https://www.rfc-editor.org/info/bcp79
[8]: https://www.ietf.org/tools/idnits/
[9]: https://www.rfc-editor.org/rfc/rfc3967.html
[10]: https://www.rfc-editor.org/info/bcp97
[11]: https://www.rfc-editor.org/rfc/rfc8126.html
[12]: https://www.rfc-editor.org/rfc/rfc2026.html#section-5
[13]: https://www.rfc-editor.org/rfc/rfc2026.html#section-4.1
[14]: https://www.rfc-editor.org/rfc/rfc2026.html#section-4.2
[15]: https://authors.ietf.org/en/content-guidelines-overview
[16]:
https://www.ietf.org/about/groups/iesg/statements/normative-informative-references/
[17]: https://datatracker.ietf.org/doc/downref/