IMAP MESSAGELIMIT Extension
draft-ietf-extra-imap-messagelimit-10

[Ballot comment]
# Gunter Van de Velde, RTG AD, comments for draft-ietf-extra-imap-messagelimit-10

## Many thanks for writing this document. I found the text easy to process even when not being a IMAP expert.

#GENERIC COMMENTS
#================
##


#DETAILED COMMENTS
#=================
##classified as [minor] and [major]

155         The server doesn't allow more than  \Deleted messages to be
156         operated on by a single UID EXPUNGE command.  The lowest
157         processed UID is .  The client needs to repeat the
158         operation for remaining messages, if required.

[minor]
Is there a reason why a backslash is used before \Deleted instead of only Deleted?
(i do not hav esignificant IMAP knowledge, but at first glance this looks as an odd construct)

523 Index
524
525   M
526
527       M
528
529         MESSAGELIMIT (response code)
530             Section 3.1, Paragraph 2.2.1

[minor]
Are the above lines supposed to be in the reference section? they look as a left over from a copy/paste

[Ballot comment]
I am also a little worried that breaking old clients with no good error reporting is going to become an issue. The methods described in the document push the failure into the future, but seems to not meanwhile cause client warnings that they should do something (upgrade). I am assuming no better error handling is possible with IMAP ?

NITS:

  C: 05 UID COPY 18000:21000 "Trash"

It seems a bit weird to COPY (instead of MOVE) messages to a Trash? Maybe rename "Trash" to "Backup" ?

[Ballot comment]
** Section 7.1
  IMAP4 capabilities are registered by publishing a standards track or
  IESG approved Informational or Experimental RFC.  The registry is
  currently located at:
      https://www.iana.org/assignments/imap-capabilities/

Could the rational for the first sentence be provided?  Technically, the “IMAP Capabilities” registry has an “IETF Review” policy.  In theory, a BCP status document would also qualify.  However, why would this document have to explain the registration policy of a registry it is not creating.  Is that the first sentence needed?

Perhaps this entire section could just read:

NEW (proposed)

IANA is requested to add the registrations of the capability names of "MESSAGELIMIT=" and "SAVELIMIT=" to the “IMAP Capabilities” registry (https://www.iana.org/assignments/imap-capabilities/imap-capabilities.xhtml#imap-capabilities-1) and use this document for the reference for both entries.

[Ballot comment]
Thanks for the work done in this document.

I have a real concern on how this new system can be deployed with 'new' servers and 'legacy' clients especially for the COPY operations if part of the COPY is not done, i.e., could be run multiple times by the end user :-( I fear that section 4.2 is too optimistic on this deployment issue. Why not having a negotiation between client and server and for legacy not implementing this limit ?

Note: I may have misunderstood the proposal.

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

IANA has completed its review of draft-ietf-extra-imap-messagelimit-08. 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 Internet Message Access Protocol (IMAP) Capabilities Registry located at:

https://www.iana.org/assignments/imap-capabilities/

two new capabilities are to be registered as follows:

Capability Name: MESSAGELIMIT=
Reference: [ RFC-to-be ]

Capability Name: SAVELIMIT=
Reference: [ RFC-to-be ]

IANA Note --> In Section 6.1 of the current draft, the URI provided is not the current URI for the IMAP Capabilities registry. Could it be changed in a future revision to the URI above?

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 2024-03-25):

From: The IESG
To: IETF-Announce
CC: arnt.gulbrandsen@icann.org, brong@fastmailteam.com, draft-ietf-extra-imap-messagelimit@ietf.org, extra-chairs@ietf.org, extra@ietf.org, superuser@gmail.com
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (IMAP MESSAGELIMIT Extension) to Experimental RFC


The IESG has received a request from the Email mailstore and eXtensions To
Revise or Amend WG (extra) to consider the following document: - 'IMAP
MESSAGELIMIT Extension'
  as Experimental RFC

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 2024-03-25. 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


  The MESSAGELIMIT extension of the Internet Message Access Protocol
  (RFC 3501/RFC 9051) allows servers to announce a limit on the number
  of messages that can be processed in a single
  FETCH/SEARCH/STORE/COPY/MOVE/APPEND/EXPUNGE command.  This helps
  servers to control resource usage when performing various IMAP
  operations.  This helps clients to know the message limit enforced by
  corresponding IMAP server and avoid issuing commands that would
  exceed such limit.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-extra-imap-messagelimit/



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

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

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?

Quite broad agreement, of those who participated.  It was decided to make it
experimental as it is a significant change to IMAP semantics.

There are industry players who have already implemented an initial pass at this,
and we're keen to publish it so they can interoperate, while remaining as an
experimental extension.

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

The main areas of discussion were around interaction with all the other IMAP
extensions and whether they had been sufficiently thought through, but there
was no real controversy.

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)?

There are implementations at Yahoo, Google, and Microsoft - and at least
some pre-release experimentation has been done by Apple.

## 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, there's no other reviews that would be relevant.

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.

There are no formal reviews required.

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.

The ABNF was validated for syntax correctness using the ABNF validator on
author-tools.

## 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, this document is clear and sufficient for an experimental standard.

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?

No common issue review is required here.

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?

Experimental is right here because of the significant change to the IMAP model
being proposed.

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, authors have been contacted and reminded of their IPR requirements.
Nothing has been disclosed.

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.  There are 4 authors who have showing willingness to be listed.

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 known nits.

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

The only informative reference is only used in an example.  The others are normative
because this document describes changes to their behaviour.

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 to other IETF documents.

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 text of the IANA considerations specify both the MESSAGELIMIT= and SAVELIMIT=
entries in the IMAP capabilities register, which matches the text in the rest of
the document.

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.

No new registries are created.

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

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?

Quite broad agreement, of those who participated.  It was decided to make it
experimental as it is a significant change to IMAP semantics.

There are industry players who have already implemented an initial pass at this,
and we're keen to publish it so they can interoperate, while remaining as an
experimental extension.

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

The main areas of discussion were around interaction with all the other IMAP
extensions and whether they had been sufficiently thought through, but there
was no real controversy.

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)?

There are implementations at Yahoo, Google, and Microsoft - and at least
some pre-release experimentation has been done by Apple.

## 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, there's no other reviews that would be relevant.

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.

There are no formal reviews required.

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.

The ABNF was validated for syntax correctness using the ABNF validator on
author-tools.

## 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, this document is clear and sufficient for an experimental standard.

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?

No common issue review is required here.

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?

Experimental is right here because of the significant change to the IMAP model
being proposed.

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, authors have been contacted and reminded of their IPR requirements.
Nothing has been disclosed.

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.  There are 4 authors who have showing willingness to be listed.

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 known nits.

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

The only informative reference is only used in an example.  The others are normative
because this document describes changes to their behaviour.

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 to other IETF documents.

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 text of the IANA considerations specify both the MESSAGELIMIT= and SAVELIMIT=
entries in the IMAP capabilities register, which matches the text in the rest of
the document.

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.

No new registries are created.

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

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?

Quite broad agreement, of those who participated.  It was decided to make it
experimental as it is a significant change to IMAP semantics.

There are industry players who have already implemented an initial pass at this,
and we're keen to publish it so they can interoperate, while remaining as an
experimental extension.

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

The main areas of discussion were around interaction with all the other IMAP
extensions and whether they had been sufficiently thought through, but there
was no real controversy.

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)?

There are implementations at Yahoo, Google, and Microsoft - and at least
some pre-release experimentation has been done by Apple.

## 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, there's no other reviews that would be relevant.

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.

There are no formal reviews required.

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.

The ABNF was validated for syntax correctness using the ABNF validator on
author-tools.

## 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, this document is clear and sufficient for an experimental standard.

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?

No common issue review is required here.

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?

Experimental is right here because of the significant change to the IMAP model
being proposed.

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, authors have been contacted and reminded of their IPR requirements.
Nothing has been disclosed.

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.  There are 4 authors who have showing willingness to be listed.

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 known nits.

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

The only informative reference is only used in an example.  The others are normative
because this document describes changes to their behaviour.

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 to other IETF documents.

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 text of the IANA considerations could be a little clearer (specifying both
MESSAGELIMIT= and SAVELIMIT= explicitly, however this should be easily resolved
when the IANA registration is done.

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.

No new registries are created.

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

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?

Quite broad agreement, of those who participated.  It was decided to make it
experimental as it is a significant change to IMAP semantics.

There are industry players who have already implemented an initial pass at this,
and we're keen to publish it so they can interoperate, while remaining as an
experimental extension.

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

The main areas of discussion were around interaction with all the other IMAP
extensions and whether they had been sufficiently thought through, but there
was no real controversy.

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)?

There are implementations at Yahoo and at least some pre-release experimentation
has been done by Apple.

## 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, there's no other reviews that would be relevant.

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.

There are no formal reviews required.

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.

The ABNF was validated for syntax correctness using the ABNF validator on
author-tools.

## 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, this document is clear and sufficient for an experimental standard.

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?

No common issue review is required here.

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?

Experimental is right here because of the significant change to the IMAP model
being proposed.

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, authors have been contacted and reminded of their IPR requirements.
Nothing has been disclosed.

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.  There are 4 authors who have showing willingness to be listed.

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 known nits.

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

The only informative reference is only used in an example.  The others are normative
because this document describes changes to their behaviour.

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 to other IETF documents.

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 text of the IANA considerations could be a little clearer (specifying both
MESSAGELIMIT= and SAVELIMIT= explicitly, however this should be easily resolved
when the IANA registration is done.

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.

No new registries are created.