Deprecation Of The IPv6 Router Alert Option For New Protocols
draft-ietf-6man-deprecate-router-alert-13

Received changes through RFC Editor sync (changed state to RFC, created became rfc relationship between draft-ietf-6man-deprecate-router-alert and RFC 9805, changed IESG state to RFC Published)

[Ballot comment]
Hi Ron, Erik,

Thank you for addressing the DISCUSS points [1].

I still hope we can address this comment:

# A better title to reflect the intent

OLD: Deprecation Of The IPv6 Router Alert Option
NEW: Deprecation of the IPv6 Router Alert Option Use by New Protocols

Cheers,
Med

[1] https://mailarchive.ietf.org/arch/msg/ipv6/f1i9pOvbMlUrt6XS6cDLidtvPZI/

[Ballot comment]
Thanks to the authors for addressing my discussion points.

For the benefit of the authors and the responsible AD, I am listing below the major comments that I would appreciate being clarified/update.

< Related to IANA - so deferring to IANA team mostly >

1) Should the Router Alert Options values registry be "closed" or should all the unassigned and experimental values be marked "reserved" so no further allocations can be made.

2) The tag of "deprecated" on the Router Alert Option seems incorrect since in this case, it is not "not recommended to be used". In this case, it is "not recommended to be used for new protocols" and therefore, IMHO, we need "deprecated for new protocols" in the IANA. This is new/different but this situation is different.

< for the authors >

3) The title of the draft should include "... for New Protocols" . Refer comments by Med and Eric.

[Ballot comment]
Thank you for a very nicely written document and I fully support its intent. I have no additional comments above what have already been raised by Ketan and Med (which i support) so am balloting Yes assuminng that those DISCUSS points will be addressed before publication.

[Ballot comment]
In Section 1, should "Router Option" be "Router Alert Option"?

In Section 3, don't present it as "One approach would be to" do the thing in this draft which "would allow" certain benefits; if this is going to RFC, we've clearly decided this is the path forward. Be less conditional and focus on the present and future: "Because..., deprecation allows...."

In Section 4, consider s/may continue to use/are currently known to use/, since it's not guaranteed you have an exhaustive list of niche and rarely deployed protocols. Similarly, in Appendix A, I'd suggest "that are known to use" rather than "that use".

In Section 6, I question whether marking something as deprecated in itself mitigates all security issues with it. There are still steps routers need to take to protect themselves, as previously described, because they can't rely on attackers to comply with this RFC. I'd suggest instead referencing those RFCs for existing security considerations and stating that routers can mitigate attacks by ignoring the option unless explicitly configured to inspect it.

[Ballot comment]
I am in support for the discuss from Ketan and Med.

Thank you for putting together this draft, it's well written and does a great job explaining the motivation behind the proposed deprecation.

One small note: the way "deprecation" is used in the draft doesn’t fully align with how IANA typically handles the term in registry language (=use is not recommended). For reference, RFC 8126, Section 9.6 (https://datatracker.ietf.org/doc/html/rfc8126#section-9.6) offers some helpful guidance, and additional aspects on the distinction between deprecated and obsolete status in IANA registries. For this document the usage of the code points is still perfectly good, hence "use is not recommended" does not really apply. However, if there is a new application that intends to request a code-point then that will be frowned upon going forward.

relevant RFC 8126 text
"
  Specific entries in a registry can be marked as "obsolete" (no longer
  in use) or "deprecated" (use is not recommended).
"

From this perspective, i support the proposal from Ketan to have this document explicit reserve the unassigned/experimental code points as suggested in Ketan's DISCUSS#2 as that will align the draft understanding of the term "deprecated" with the IANA understanding of the term "deprecated"

I also feel that the title could be made slightly more clear as both Med and Eric V observed in their ballot reviews.

[Ballot discuss]
There are a few aspects in this document that I would like to discuss - I believe most of them (baring the last one perhaps) are more of a process concern than the sum and substance of the proposal itself:

< discuss-1 > "Deprecate" vs "Obsolete" - lack of clarity and ambiguity. My understanding is that this is a 'conditional deprecation' of a protocol element since existing protocols as well as new versions of the same protocol are allowed to use RA. Therefore, should the document not "update" RFC2711 that remains a valid and correct RFC reference for protocols that continue to use RA and their future extension documents?

< discuss-2 > Regarding the IANA Considerations, should this document not be more precise and explicit to "reserve" all the unassigned and experimental use codepoints in the IPv6 Router Alert Values registry along with this document as a reference both on those specific codepoints but also on the registry itself? Further, it would be more appropriate to indicate "Deprecated for New Protocol Use" instead of just "Deprecated" against the Router Alert HBH Option itself?

< discuss-3 > Regarding which protocols can continue to use RA - some clarity would help here. We have the IANA registry for the IPv6 Router Alert Values, then we have the table in Appendix A, and finally some protocols referenced in the body of the document itself. My understand is that, all protocols for which code points have been allocated may continue to use RA. Is that correct? If so, such a statement would be helpful. Also, inserting a column in the table in the appendix with the RA value would be helpful (quoting the experimental range for experimental specs should be ok?).

[Ballot comment]
I agree with the comments from Med and Eric - not repeating them here though I have "up-leveled" some of them to discussion points.

[Ballot comment]

# Éric Vyncke, INT AD, comments for draft-ietf-6man-deprecate-router-alert-09
CC @evyncke

Thank you for the work put into this document even if I wonder whether RFC 8200 stance about HbH being optional to parse is not enough.

Please find below some non-blocking COMMENT points (but replies would be appreciated even if only for my own education).

Special thanks to Bob Hinden for the shepherd's detailed write-up including the WG consensus _but it lacks_ the justification of the intended status.

Other thanks to Bob Halley , the Internet directorate reviewer (at my request):
https://datatracker.ietf.org/doc/review-ietf-6man-deprecate-router-alert-08-intdir-telechat-halley-2025-03-08/

I hope that this review helps to improve the document,

Regards,

-éric

## COMMENTS (non-blocking)

### Title

Like Med Boucadair, strongly suggest to make the title clearer with "Deprecation of the IPv6 Router Alert Option Use by New Protocols".

### Obsoleting RFC 2711

As router alert will become deprecated and not historic, I wonder whether this I-D can/should update RFC 2711 rather than obsoleting it.

### Section 1

Please note that IANA uses "protocol number" or extension header type in https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#extension-header rather than `each one identified by a distinct Next Header value`.

While English is not my primary language, what about s/the Router Alert Option introduces many issues/the Router Alert Option *has introduced* many issues/

What about adding "future versions" in `Implementers of protocols that continue to use the Router Option can continue to reference [RFC2711] for Router Alert Option details.` to match the abstract and be more useful/practical ?

### Section 6

It seems that `This document mitigates all security considerations` is too strong as current use of router alert can continue. Strongly suggest adding "for future protocols".

### Section 7

I support Med Boucadair's and Roman Danyliw's issues about being stricter and more precise for the IANA.

[Ballot comment]
Thank you to Mallory Knodel for the GENART review.

** Section 7
  IANA is requested to mark the Router Alert Option as "Deprecated" in
  the Destination Options and Hop-by-hop Options Registry (
  https://www.iana.org/assignments/ipv6-parameters/
  ipv6-parameters.xhtml#ipv6-parameters-2) and add a pointer to this
  document.

To aid the reader, be explicit that marking something as being “Deprecated” means renaming the code point by adding a suffix of “(DEPRECATED)”.

It’s a curious, but undocumented convention which isn’t covered by RFC8200, RFC2780, or RFC9673 which manage this registry.  Not to be done in this document, but an explicit column could be added to these registries in this group.  Some notion of status in a distinct column is a common practice in other registries.

[Ballot comment]
The current problems originate from the way in which routers are required to action a Router Alert. I understand this I-D does not change any existing RFC, but seeks to restrict usage in new specifications. Thank you, it is well written.

Note: It is a little sad that the I-D does not offer an alternative to identify packets sent by future protocols (such as protocols operating like RSVP would in future be identified in a network that wished to use this type of signalling to nodes on the path), this is presumably part of any future work.

[Ballot discuss]
Hi Ron,

Thank you for pushing for this work. I fully support the intent and scope.

Thanks to Sheng Jiang for the two opsdir reviews.

I have two points to DISCUSS. Will be balloting "Yes" once resolved.

# IPv6 Router Alert Option Values

Do we have any action to do for https://www.iana.org/assignments/ipv6-routeralert-values/ipv6-routeralert-values.xhtml? Do we need to add a note about deprecation or even say that the registry is closed for assignment? Else?

# (for the AD/Chairs) Use by Other SDOs

For example, we used to have:

=
2.10 RFC2711 - IPv6 Router Alert Option

  The Router Alert Option [RFC-2711] must be supported,
=

That was removed since then in 7066, but these specs do not intend the interpret 3GPP specifications or mirror them.

I don’t know if a check was made about the use by other SDOs, but I guess we need at least to send an LS about the deprecation to 3GPP (BBF?).

[Ballot comment]
# A better title to reflect the intent

OLD: Deprecation Of The IPv6 Router Alert Option
NEW: Deprecation of the IPv6 Router Alert Option Use by New Protocols

# Nit

OLD:
  In IPv6 [RFC8200], optional internet-layer information is encoded in
  separate headers that may be placed between the IPv6 header and the
  upper-layer header in a packet.

NEW:
  In IPv6 [RFC8200], optional information is encoded in
  separate headers that may be placed between the IPv6 header and the
  upper-layer header in a packet.

Or

NEW2:
  In IPv6 [RFC8200], optional IP-layer information is encoded in
  separate headers that may be placed between the IPv6 header and the
  upper-layer header in a packet.

# nit

CURRENT:
  There is a small number of such
  extension headers, each one identified by a distinct Next Header
  value.

“such extension headers”: EH was not exactly mentioned in the previous sentence. Maybe say that “separate headers" are called extension headers?

# Do we need to mention this?

CURRENT:
  There is a small number of such

# nit

OLD:
  So, network operators can address the security considerations raised
  in [RFC6398] by:

NEW:
  Typically, network operators can address the security considerations raised
  in [RFC6398] by:

IESG/Authors/WG Chairs:

IANA has completed its review of draft-ietf-6man-deprecate-router-alert-06. If any part of this review is inaccurate, please let us know.

IANA understands that, upon approval of this document, there is a single action which we must complete.

In the Destination Options and Hop-by-Hop Options registry in the Internet Protocol Version 6 (IPv6) Parameters registry group located at:

https://www.iana.org/assignments/ipv6-parameters/

the following option will be marked as DEPRECATED:

Hex Value: 0x05
Binary value (act): 00
Binary Value (chg): 0
Binary value (rest): 00101
Description: Router Alert
Reference: [ RFC-to-be ]

A note will be added to the registry as follows:

[ RFC-to-be ] has DEPRECATED the Router Alert option. Protocols that use the Router Alert Option may continue to do so, even in future versions. However, new protocols that are standardized in the future must not use the Router Alert Option. See [ RFC-to-be ] for details.

We understand that this is the only action required to be completed upon approval of this document.

NOTE: The action requested in this document will not be completed until the document has been approved for publication as an RFC. This message is meant only to confirm the action that will be performed.

For definitions of IANA review states, please see:

https://datatracker.ietf.org/help/state/draft/iana-review

Thank you,

David Dong
IANA Services Sr. Specialist

The following Last Call announcement was sent out (ends 2025-02-12):

From: The IESG
To: IETF-Announce
CC: 6man-chairs@ietf.org, bob.hinden@gmail.com, draft-ietf-6man-deprecate-router-alert@ietf.org, ek.ietf@gmail.com, ipv6@ietf.org
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (Deprecation Of The IPv6 Router Alert Option) to Proposed Standard


The IESG has received a request from the IPv6 Maintenance WG (6man) to
consider the following document: - 'Deprecation Of The IPv6 Router Alert
Option'
  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
last-call@ietf.org mailing lists by 2025-02-12. 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


  This document deprecates the IPv6 Router Alert Option.  Protocols
  that use the Router Alert Option may continue to do so, even in
  future versions.  However, new protocols that are standardized in the
  future must not use the Router Alert Option.

  This document obsoletes RFC 2711.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-6man-deprecate-router-alert/



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

# Internet AD comments for draft-ietf-6man-deprecate-router-alert-05
CC @ekline

* comment syntax:
  - https://github.com/mnot/ietf-comments/blob/main/format.md

## Nits

### S1

* "here is no need to closely examine this datagram more closely"
  ->
  "here is no need to examine this datagram more closely"

### S9.1

* ID nits says:

  == Unused Reference: 'RFC4291' is defined on line 210, but no explicit
    reference was found in the text

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

  Title:  Deprecation Of The IPv6 Router Alert Option
  Author:  Ron Bonica
  Name:    draft-ietf-6man-deprecate-router-alert-05.txt
  Pages:  8
  Dates:  2025-01-26

  The IETF datatracker status page for this Internet-Draft is:
  https://datatracker.ietf.org/doc/draft-ietf-6man-deprecate-router-alert/

Thank you for your service as a document shepherd. Among the responsibilities is
answering the questions in this write-up to give helpful context to Last Call
and Internet Engineering Steering Group ([IESG][1]) reviewers, and your
diligence in completing it is appreciated. The full role of the shepherd is
further described in [RFC 4858][2]. You will need the cooperation of the authors
and editors to complete these checks.

Note that some numbered items contain multiple related questions; please be sure
to answer all of them.

## Document History

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?

Reasonable consensus to advance.  No objections. The topic has been
discussed for a long time in 6MAN and this draft formalises the discussion.

2. Was there controversy about particular points, or were there decisions where
  the consensus was particularly rough?

Good agreement of basic idea of deprecating the router alert option.
More discussion on what "deprecate" means, the document makes that clear.

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.)

No.

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)?

No, but relavant for a deprecation document.

## 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.

No.

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.

N/A

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, the 6MAN chairs did a review, the current version (05) addresses
issues raised.

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?

Standards Track, Proposed Standard

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, the author confirmed he was not aware of any IPR.

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.

Yes

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.)

No issues, except for one unused reference, this can be removed later.

15. Should any informative references be normative or vice-versa? See the [IESG
    Statement on Normative and Informative References][16].

References look fine (except as noted in 14.)

16. List any normative references that are not freely available to anyone. Did
    the community have sufficient access to review any such normative
    references?

All references are published RFCs.

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.

Yes, this document obsoletes RFC 2711.  Correctly listed in header,
Abstract, and Introduction.

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 document requests IANA to mark the Router Alert option as
deprecated.  It says:

  IANA is requested to mark the Router Alert Option as Deprecated in
  the Destination Options and Hop-by-hop Options Registry (
  https://www.iana.org/assignments/ipv6-parameters/
  ipv6-parameters.xhtml#ipv6-parameters-2) and add a pointer to this
  document.

  IANA include a note describing how this document uses the word
  "deprecate".  Text can be take from the abstract of this document.

The relavant text in the Abstract is:

  Protocols that use the Router Alert Option may continue to do so, even
  in future versions.  However, new protocols that are standardized in
  the future must not use the Router Alert Option.

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.

N/A

[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/

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

  Title:  Deprecation Of The IPv6 Router Alert Option
  Author:  Ron Bonica
  Name:    draft-ietf-6man-deprecate-router-alert-05.txt
  Pages:  8
  Dates:  2025-01-26

  The IETF datatracker status page for this Internet-Draft is:
  https://datatracker.ietf.org/doc/draft-ietf-6man-deprecate-router-alert/

Thank you for your service as a document shepherd. Among the responsibilities is
answering the questions in this write-up to give helpful context to Last Call
and Internet Engineering Steering Group ([IESG][1]) reviewers, and your
diligence in completing it is appreciated. The full role of the shepherd is
further described in [RFC 4858][2]. You will need the cooperation of the authors
and editors to complete these checks.

Note that some numbered items contain multiple related questions; please be sure
to answer all of them.

## Document History

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?

Reasonable consensus to advance.  No objections. The topic has been
discussed for a long time in 6MAN and this draft formalises the discussion.

2. Was there controversy about particular points, or were there decisions where
  the consensus was particularly rough?

Good agreement of basic idea of deprecating the router alert option.
More discussion on what "deprecate" means, the document makes that clear.

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.)

No.

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)?

No, but relavant for a deprecation document.

## 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.

No.

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.

N/A

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, the 6MAN chairs did a review, the current version (05) addresses
issues raised.

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?

Standards Track, Proposed Standard

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, the author confirmed he was not aware of any IPR.

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.

Yes

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.)

No issues, except for one unused reference, this can be removed later.

15. Should any informative references be normative or vice-versa? See the [IESG
    Statement on Normative and Informative References][16].

References look fine (except as noted in 14.)

16. List any normative references that are not freely available to anyone. Did
    the community have sufficient access to review any such normative
    references?

All references are published RFCs.

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.

Yes, this document obsoletes RFC 2711.  Correctly listed in header,
Abstract, and Introduction.

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 document requests IANA to mark the Router Alert option as
deprecated.  It says:

  IANA is requested to mark the Router Alert Option as Deprecated in
  the Destination Options and Hop-by-hop Options Registry (
  https://www.iana.org/assignments/ipv6-parameters/
  ipv6-parameters.xhtml#ipv6-parameters-2) and add a pointer to this
  document.

  IANA include a note describing how this document uses the word
  "deprecate".  Text can be take from the abstract of this document.

The relavant text in the Abstract is:

  Protocols that use the Router Alert Option may continue to do so, even
  in future versions.  However, new protocols that are standardized in
  the future must not use the Router Alert Option.

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.

N/A

[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/