Update to the IANA CoAP Content-Formats Registration Procedures
draft-ietf-core-cf-reg-update-09

[Ballot comment]
Thanks for addressing my concerns and confirming IANA is aware of the structure and instructions of the document and is in agreement. I have updated my ballot to No Objection.

[Ballot comment]

# Éric Vyncke, INT AD, comments for draft-ietf-core-cf-reg-update-08
CC @evyncke

Thank you for the work put into this document.

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

Special thanks to Marco Tiloca for the shepherd's detailed write-up including the WG consensus, *the IANA discussion*, and the justification of the intended status.

Other thanks to Renzo Navas, the IoT directorate reviewer (at my request):
https://datatracker.ietf.org/doc/review-ietf-core-cf-reg-update-07-iotdir-telechat-navas-2025-04-18/ (and I have read Thomas' replies)

I hope that this review helps to improve the document,

Regards,

-éric

## COMMENTS (non-blocking)

### Use of SVG graphics

Thanks for using SVG graphics for the tables

### IANA updates

Thanks to the shepherd's write-up, I think that the unusual structure of this document is actually correct as the IANA has been part of the discussion (thank you, Amanda Baber)

### Sections 3, 3.5, and 3.7

Probably worth explaining that 64999 is now reserved by this document for documentation/example. A nice idea.

_BUT_, section 3.5 also uses 64900 in an example => please request *two* documentation values for ID.

### Section 6.1

I strongly think that this section should not be removed, if only to leave an audit trail on the note removal.

[Ballot discuss]
I also feel the structure of this document is very strange. It updates another RFC's IANA Considerations section, outside its own IANA Considerations Section. And then does not repeat the actual IANA changes in the document's IANA Consideration's section.

It also seems all the "bad examples" are really instructions for the Designated Experts, which we usually also place in the IANA Considerations Section.

I think we should at least have a discussion with IANA.

[Ballot discuss]
Thanks to the authors and WG for this document to fix the issues with IANA allocation.

I have one uber comment about the structure of this document that IMHO raises to the level of a DISCUSS but should be easy to resolve. Much of the sum and substance of this document (which is section 4) should have been under the IANA Considerations section since they are really ... IANA considerations.

Additionally, the style of referencing section numbers (and introducing sub-sections) in RFC7252 is very confusing. Why not say that the IANA Considerations in this section replace the entire Section 12.3 of RFC7252 and rewrite the considerations as new?

"4.2. New Section 12.3.1 "Temporary Content-Format Registrations"" ... seems very odd.

IOW request the authors/WG to please simplify this patch.

[Ballot comment]
Hi Thomas/Esko,

Thank you for addressing the DISCUSS points (mark 64999 as reserved for documentation + "One Range, one Policy") and grabbing whatever useful for you from the comments.

Cheers,
Med

[1] https://mailarchive.ietf.org/arch/msg/core/a5xaEVG9TyY_vO8WjSxYeWjyC-w/

[Ballot discuss]
Hi Thomas, Esko,

Thanks for the effort put into this specification.

The combination of 8126 policies is interesting. I trust this can be further socialized in the context of IANAbis.

I have two easy DISCUSS points and a few comments.

# DISCUSSS

## Should we formally mark 64999 as reserved for documentation?

CURRENT:
  All the example registration requests use a CoAP Content-Format with
  identifier 64999 in the FCFS range of the "CoAP Content-Formats"
  registry.

## "One Range, one Policy" instead of "One Range, Two conditional Policies"

CURRENT:
  The 10000-64999 range now has two separate registration procedures.
  If the registration consists solely of a registered media type name
  in the "Content Type" field, without any parameter names or "Content
  Coding", and the media type has not yet been used in this registry,
  then the policy is FCFS, as before.  In all other cases, the policy
  is "Expert Review," following the procedure described in Section 4.4.

Given the size of the range, wouldn’t be simple for IANA to dedicate a range for “simple registrations” and another one for more complex ones?

[Ballot comment]
# There are many Updates

Please update the title accordingly:

OLD: Update to the IANA CoAP Content-Formats Registration Procedures
NEW: Updates to the IANA Constrained Application Protocol (CoAP) Content-Formats Registration Procedures

Note that this is consistent with this part from the introduction:

CURRENT:
  These
  updates amend the different ranges of the registry, introduce a
  review procedure to be performed for most ranges of the registry,

# Abstract should be self-contained

OLD:
  This document updates RFC 7252 regarding the registration procedures
  for the "CoAP Content-Formats" IANA registry, within the "Constrained
  RESTful Environments (CoRE) Parameters" registry group.  This
  document also introduces a new column, "Media Type", to the registry.


NEW:
  This document updates RFC 7252 (The Constrained Application Protocol (CoAP)) regarding the registration procedures^
                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  for the "CoAP Content-Formats" IANA registry, within the "Constrained
  RESTful Environments (CoRE) Parameters" registry group.  This
  document also introduces a new column, "Media Type", to that registry.
                                                          ^^^^
# Format as a plain sentence

OLD:
  (Note that the columns of this registry have
  been revised according to [Err4954].)

NEW:
  Note that the columns of this registry have
  been revised according to [Err4954].

# Which text?

OLD: In particular, the text defines
NEW: In particular, Section 12.3 of [RFC7252] defines

# Maybe better to cite rfc8126#section-4.4 rather than re-defining the policy. I would delete the following:

CURRENT:
  For the FCFS range,
  these rules do not involve the Designated Expert (DE) and are managed
  solely by IANA personnel to finalize the registration.

# Which instructions are we referring to here?

CURRENT:
  Unfortunately, the instructions do not explicitly require checking
  that the combination of content-type (i.e., media type with optional

# Add a pointer to the section where to look for examples

OLD:
  and should not be solely demanded from the registrar.  This lack of
  guidance may engender confusion in both the registering party and the
  registrar, and has already led to erroneous registrations.

NEW:
  and should not be solely demanded from the registrar.  This lack of
  guidance may engender confusion in both the registering party and the
  registrar, and has already led to erroneous registrations (Section 3).

# “Current” will be stale

OLD:
  This section provides examples of registration requests for the "CoAP
  Content-Formats" Registry (as defined in Section 12.3 of [RFC7252]
  and revised according to [Err4954]) that are invalid but would be
  approved under the current procedure. 

NEW:
  This section provides examples of registration requests for the "CoAP
  Content-Formats" Registry (as defined in Section 12.3 of [RFC7252]
  and revised according to [Err4954]) that are invalid but would be
  approved under the old procedure.

Or

NEW:
  This section provides examples of registration requests for the "CoAP
  Content-Formats" Registry (as defined in Section 12.3 of [RFC7252]
  and revised according to [Err4954]) that are invalid but would be
  approved under the procedure in [RFC7252].

# Better clarity

OLD:
  For each of the following example registration requests, one can
  create a similar instance where the requested registration is for a
  CoAP Content-Format identifier within the "IETF Review" or "IESG
  Approval" range of the registry.  Similarly, such registrations must
  not be granted.

NEW:
  For each of the following example registration requests, one can
  create a similar instance where the requested registration is for a
  CoAP Content-Format identifier within the "IETF Review" or "IESG
  Approval" range.  Such registrations must not be granted.

# Example URI

CURRENT:
  In this example, the eat_profile parameter value (which can be any
  URI) is set as a Uniform Resource Name (URN) [RFC8141].  Since for
  URNs, the Namespace Identifier (foo in the example) is defined as
  case insensitive, the two registrations are semantically identical.

For consistency with other specs (rfc8407bis, for example), consider using “example” instead of “foo”.

# Virtual?

CURRENT:
  This section updates Section 12.3 of [RFC7252] and introduces four
  new “virtual” subsections, 12.3.1 to 12.3.4.

These are not virtual but concrete additions to 7252. I suggest we delete that mention.

# More than one DE

OLD:
  The Designated Expert (DE) is instructed to perform the Expert
  Review, as described by the following checklist:

NEW:
  A Designated Expert (DE) is instructed to perform the Expert
  Review, as described by the following checklist:

More than one DE is usually appointed, while the OLD seems to assume that there is one single DE.

Cheers,
Med

IESG/Authors/WG Chairs:

IANA has completed its review of draft-ietf-core-cf-reg-update-05. If any part of this review is inaccurate, please let us know.

IANA has questions about the actions requested in the IANA Considerations section of this document.

IANA understands that, upon approval of this document, this document is entirely about registration procedures in a single registry.

The registry whose registration procedures are being modified is the CoAP Content-Formats registry in the Constrained RESTful Environments (CoRE) Parameters registry group located at:

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

First, IANA understands that the registration procedure for this registry is to be changed from:

0-255 Expert Review
256-9999 IETF Review or IESG Approval
10000-64999 First Come First Served
65000-65535 Experimental use (no operational use)

to the following:

0-255 | Expert Review | See RFCthis, Section 4.4
256-9999 | IETF Review with Expert Review or IESG Approval with Expert Review | See RFCthis, Section 4.4
10000-64999 | Expert Review or First Come First Served | See RFCthis, Section 4.4. FCFS is allowed if the registration has no parameters, has an empty Content Coding, the media type is not yet used in this registry, and the media type is registered (or approved for registration) in the "Media Types" registry. Expert Review is required if the registration includes parameters, and/or includes a Content Coding, and/or the media type appears in this registry.
65000-65535 | Experimental Use | No operational use

Second, a new column is added to the registry with the title of "Notes."

Third, the current draft in Section 4.2 discusses the ability to make temporary registrations in the 0-255 and 256-9999 ranges of the registry. In both Section 4.1 and 4.2, the authors apply [RFC7120] to the proposed expert review process, but those sections do not match what is in Section 3 of [RFC7120].

IANA Question --> Do the authors desire to apply the entire procedure of Section 3 of [RFC7120] to the 0-255 and 256-9999 ranges of the registry? This would include 1) the WG chair request registration after getting AD approval (IANA would then ask the experts), and 2) after the first renewal, the full IESG would have to approve?

IANA believes that, for the CoAP Content-Formats registry, the current draft needs more clarity about the full rules for applying the procedure for temporary registrations in this registry.

Fourth, also in Section 4.2, the authors make this request: "A temporary registration is marked by IANA with the label "TEMPORARY" in the corresponding registry entry." This is currently problematic for IANA.

IANA Question --> Could this be changed to "A temporary registration is marked as such by IANA in the corresponding registry entry"? Changing "TEMPORARY" to lower case gives IANA the flexibility in how it visually designates and signifies temporary allocations.

Fifth, a new column is to be added to the registry with the title of "Media Type" and will be placed directly to the right of the existing "Content Type" column. In the second paragraph of Section 4.3, the authors request that, "If a provisional media type is later abandoned or becomes a permanent media type, IANA must update the 'Media Type' field in the associated entries. In the case of abandonment, this field should be left empty."

IANA Question --> In this specific case, wouldn't IANA be required to remove the Content-Format from the registry if there's no longer an associated media type?

IANA has checked with the designated expert and IANA believes that there are no registered formats that do not have associated media types.

We understand that these are the only actions required to be addressed upon approval of this document.

NOTE: The actions requested in this document will not be completed until the document has been approved for publication as an RFC. This message is meant only to confirm the list of actions 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 2025-03-10):

From: The IESG
To: IETF-Announce
CC: core-chairs@ietf.org, core@ietf.org, draft-ietf-core-cf-reg-update@ietf.org, francesca.palombini@ericsson.com, marco.tiloca@ri.se
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (Update to the IANA CoAP Content-Formats Registration Procedures) to Proposed Standard


The IESG has received a request from the Constrained RESTful Environments WG
(core) to consider the following document: - 'Update to the IANA CoAP
Content-Formats Registration Procedures'
  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 2025-03-10. 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 updates RFC7252 regarding the registration procedures
  for the "CoAP Content-Formats" IANA registry, within the "Constrained
  RESTful Environments (CoRE) Parameters" registry group.  This
  document also introduces a new column, "Media Type", to the registry.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-core-cf-reg-update/



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

# Document Shepherd Writeup for draft-ietf-core-cf-reg-update

Document status: https://datatracker.ietf.org/doc/draft-ietf-core-cf-reg-update/

Document Shepherd: Marco Tiloca

Area Director: Francesca Palombini


## Document Summary

This document updates the "CoAP Content-Formats" IANA registry originally defined by RFC 7252, in order to mitigate the risk of unintentional or malicious errors when registering new entries.

This is motivated by the non-trivial task of correctly assessing the validity of a requested registration, particularly for registry range that uses the "First Come First Served" registration policy (RFC 8126) and therefore relies only on checks performed by IANA personnel.

In particular, this document updates the registration procedures for different ranges of the registry, by introducing a review procedure to be performed for most of those, and allowing the registration of temporary Content-Format identifiers for some ranges of the registry. Finally, this document adds a new "Media Type" column to the registry.

In so doing, this document updates RFC 7252.


## 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?

    The WG has reached broad agreement and strong consensus on this document.


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

    There has been no controversy. On the contrary, the document could also build on input and guidance from IANA personnel, which shaped part of its content and reassured about the overall direction.

    The document was welcome from the start, its development has been swift, collaborative, and smooth, and it has gone through multiple expert reviews.


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 recommends) or elsewhere (where)?

    Not applicable, as the document does not specify a protocol.


### 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 reviews have been deemed necessary from external organizations regarding the updates to the IANA registry.

  It is already the case that applications and technologies for constrained RESTful environments take advantage of the IANA registry for coordinating on the numeric identifiers of CoAP Content-Formats. The registry updates specified in this document mitigate the risk of unintentional or malicious errors when registering new entries.

  Consistently with the registry updates made by this document, the Designated Experts performing the review procedure (when required), or the IANA personnel for defined simple cases, will be responsible to assess the correctness of registration requests of new CoAP Content-Format identifiers.

  Since the inception of the document, its authors have had direct interactions with IANA personnel. This resulted in effective feedback and input to incorporate in the document, thereby ensuring that the goal of the proposed updates can be effectively achieved.

  During the Working Group Last Call, the IANABIS Working Group was also informed, highlighting that this document could serve as an interesting case study for the work being done in IANABIS.


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.

    Not applicable.


7. If the document contains a YANG module, has the final version of the module been checked with any of the recommended validation tools 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?

    Not applicable.


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.

    Not applicable.


### 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?

    The Shepherd fully supports the document and believes it to be ready.


10. Several IETF Areas have assembled lists of common issues that their reviewers encounter. For which areas have such issues been identified and addressed? For which does this still need to happen in subsequent reviews?

    None of the common issues from the IETF areas has been identified as applicable to this document.


11. What type of RFC publication is being requested on the IETF stream (Best Current Practice, Proposed Standard, Internet Standard, Informational, Experimental or Historic)? Why is this the proper type of RFC? Do all Datatracker state attributes correctly reflect this intent?

    The intended RFC status is Proposed Standard, as reflected by the Datatracker state for this document.

    This is deemed appropriate for the content and contribution of this document, i.e., updating the registration procedures and structure of an existing IANA registry, by formally updating the Proposed Standard RFC 7252 that originally defined that registry and which registration policies to use.


12. Have reasonable efforts been made to remind all authors of the intellectual property rights (IPR) disclosure obligations described in BCP 79? 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.

    Each author has stated that they do not have direct, personal knowledge of any IPR related to this document. The Shepherd is not aware of any IPR either, and no IPR discussion about this document has occurred in the CoRE WG.


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 is not enough; please review the "Content Guidelines" on authors.ietf.org.

    No I-D nits are left; the few warnings and comments raised by the idnits tool are actually fine.

    The document complies with the "Content Guidelines" on authors.ietf.org.


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

    References are listed in the appropriate category.


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 the normative references are freely available.


17. Are there any normative downward references (see RFC 3967 and BCP 97) that are not already listed in the DOWNREF registry? If so, list them.

    This document does not include any such normative reference.


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?

    This document does not include any such normative reference.


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 intends to update RFC 7252 (if approved), explaining how a registry defined in RFC 7252 will be updated in different respects.

    This document reflects this update in the title page, in the abstract, and in the 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).

    The contribution of this document is in fact a set of updates to the "CoAP Content-Formats" IANA registry, under the "Constrained RESTful Environments (CoRE) Parameters" registry group. Hence, the "IANA Considerations" section is the core content of this document.

    The "IANA Considerations" section is complete and consistent with the document body. The section well defines the updates to the registry, which are appropriately organized in different subsections.


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.

    This document does not define new IANA registries, but it updates an existing one.

    The defined updates include amendments to the different ranges of the registry, and the introduction of a review procedure to be performed for new registrations to most of those ranges. Such a review procedure is well defined, with clear and appropriate instructions to the Designated Experts.

    The original version of the registry includes a range that uses the registration policy "Expert Review", and Designated Experts are therefore already assigned to the registry. The registry updates defined in this document is not expected to impact the current set of Designated Experts already assigned to the registry.

# Document Shepherd Writeup for draft-ietf-core-cf-reg-update

Document status: https://datatracker.ietf.org/doc/draft-ietf-core-cf-reg-update/

Document Shepherd: Marco Tiloca

Area Director: Francesca Palombini


## Document Summary

This document updates the "CoAP Content-Formats" IANA registry originally defined by RFC 7252, in order to mitigate the risk of unintentional or malicious errors when registering new entries.

This is motivated by the non-trivial task of correctly assessing the validity of a requested registration, particularly for registry range that uses the "First Come First Served" registration policy (RFC 8126) and therefore relies only on checks performed by IANA personnel.

In particular, this document updates the registration procedures for different ranges of the registry, by introducing a review procedure to be performed for most of those, and allowing the registration of temporary Content-Format identifiers for some ranges of the registry. Finally, this document adds a new "Media Type" column to the registry.

In so doing, this document updates RFC 7252.


## 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?

    The WG has reached broad agreement and strong consensus on this document.


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

    There has been no controversy. On the contrary, the document could also build on input and guidance from IANA personnel, which shaped part of its content and reassured about the overall direction.

    The document was welcome from the start, its development has been swift, collaborative, and smooth, and it has gone through multiple expert reviews.


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 recommends) or elsewhere (where)?

    Not applicable, as the document does not specify a protocol.


### 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 reviews have been deemed necessary from external organizations regarding the updates to the IANA registry.

  It is already the case that applications and technologies for constrained RESTful environments take advantage of the IANA registry for coordinating on the numeric identifiers of CoAP Content-Formats. The registry updates specified in this document mitigate the risk of unintentional or malicious errors when registering new entries.

  Consistently with the registry updates made by this document, the Designated Experts performing the review procedure (when required), or the IANA personnel for defined simple cases, will be responsible to assess the correctness of registration requests of new CoAP Content-Format identifiers.

  Since the inception of the document, its authors have had direct interactions with IANA personnel. This resulted in effective feedback and input to incorporate in the document, thereby ensuring that the goal of the proposed updates can be effectively achieved.

  During the Working Group Last Call, the IANABIS Working Group was also informed, highlighting that this document could serve as an interesting case study for the work being done in IANABIS.


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.

    Not applicable.


7. If the document contains a YANG module, has the final version of the module been checked with any of the recommended validation tools 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?

    Not applicable.


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.

    Not applicable.


### 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?

    The Shepherd fully supports the document and believes it to be ready.


10. Several IETF Areas have assembled lists of common issues that their reviewers encounter. For which areas have such issues been identified and addressed? For which does this still need to happen in subsequent reviews?

    None of the common issues from the IETF areas has been identified as applicable to this document.


11. What type of RFC publication is being requested on the IETF stream (Best Current Practice, Proposed Standard, Internet Standard, Informational, Experimental or Historic)? Why is this the proper type of RFC? Do all Datatracker state attributes correctly reflect this intent?

    The intended RFC status is Proposed Standard, as reflected by the Datatracker state for this document.

    This is deemed appropriate for the content and contribution of this document, i.e., updating the registration procedures and structure of an existing IANA registry, by formally updating the Proposed Standard RFC 7252 that originally defined that registry and which registration policies to use.


12. Have reasonable efforts been made to remind all authors of the intellectual property rights (IPR) disclosure obligations described in BCP 79? 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.

    Each author has stated that they do not have direct, personal knowledge of any IPR related to this document. The Shepherd is not aware of any IPR either, and no IPR discussion about this document has occurred in the CoRE WG.


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 is not enough; please review the "Content Guidelines" on authors.ietf.org.

    No I-D nits are left; the few warnings and comments raised by the idnits tool are actually fine.

    The document complies with the "Content Guidelines" on authors.ietf.org.


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

    References are listed in the appropriate category.


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 the normative references are freely available.


17. Are there any normative downward references (see RFC 3967 and BCP 97) that are not already listed in the DOWNREF registry? If so, list them.

    This document does not include any such normative reference.


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?

    This document does not include any such normative reference.


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 intends to update RFC 7252 (if approved), explaining how a registry defined in RFC 7252 will be updated in different respects.

    This document reflects this update in the title page, in the abstract, and in the 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).

    The contribution of this document is in fact a set of updates to the "CoAP Content-Formats" IANA registry, under the "Constrained RESTful Environments (CoRE) Parameters" registry group. Hence, the "IANA Considerations" section is the core content of this document.

    The "IANA Considerations" section is complete and consistent with the document body. The section well defines the updates to the registry, which are appropriately organized in different subsections.


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.

    This document does not define new IANA registries, but it updates an existing one.

    The defined updates include amendments to the different ranges of the registry, and the introduction of a review procedure to be performed for new registrations to most of those ranges. Such a review procedure is well defined, with clear and appropriate instructions to the Designated Experts.

    The original version of the registry includes a range that uses the registration policy "Expert Review", and Designated Experts are therefore already assigned to the registry. The registry updates defined in this document is not expected to impact the current set of Designated Experts already assigned to the registry.