Security Considerations for Optimistic Protocol Transitions in HTTP/1.1
draft-ietf-httpbis-optimistic-upgrade-06

Received changes through RFC Editor sync (changed state to RFC, created became rfc relationship between draft-ietf-httpbis-optimistic-upgrade and RFC 9931, changed IESG state to RFC Published)

[Ballot comment]
### Guidance for HTTP CONNECT

```
  At the time of writing, some proxy clients are believed to be
  vulnerable as described.  As a mitigation, proxy servers MUST close
  the underlying connection when rejecting a CONNECT request, without
  processing any further requests on that connection, unless the client
  is known to wait for a 2xx (Successful) response before forwarding
  TCP payload data.  This requirement applies whether or not the
  request includes a "close" connection option.

  Note that this mitigation will frequently impair the performance of
  correctly implemented clients, especially when returning a 407 (Proxy
  Authentication Required) response.  This performance loss can be
  avoided by using HTTP/2 or HTTP/3, which are not vulnerable to this
  attack.
```

I'm struggling with the phrasing of this.

I'd try to reduce the optionality here, perhaps something like:

```
  As a mitigation, proxy servers MUST close
  the underlying connection when rejecting a CONNECT request, without
  processing any further requests on that connection, unless the client
  is known to wait for a 2xx (Successful) response before forwarding
  TCP payload data.

  At the time of writing, some proxy clients are believed to be
  vulnerable unless this mitigation is provided.

  This mitigation impairs performance, and HTTP/2 or HTTP/3 should be used instead when possible.
```

[Ballot comment]

# Éric Vyncke, INT AD, comments for draft-ietf-httpbis-optimistic-upgrade-05
CC @evyncke

Thank you for the work put into this document. Usually, I like short and dense documents, but I am afraid that this I-D is too terse to the point of being not easy to understand.

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

Special thanks to Tommy Pauly for the shepherd's detailed write-up including the WG consensus *and* the justification of the intended status.

Other thanks to Tatuya Jinmei, the Internet directorate reviewer (at my request):
https://datatracker.ietf.org/doc/review-ietf-httpbis-optimistic-upgrade-05-intdir-telechat-jinmei-2025-09-12/ (and I have read the initial discussion)

I hope that this review helps to improve the document,

Regards,

-éric

## COMMENTS (non-blocking)

### Lack of introduction

Like other ADs, I think that an introduction will be useful.

### Section 2

Should Upgrade be quoted to make it visible that it is a protocol item ? I.e., s/A request using Upgrade might be rejected/A request using "Upgrade" might be rejected/

### Section 3

Who is the "we" in `we call` ? The author ? The WG ? The IETF Community ? Please avoid using vague and ambiguous "we" (e.g., by using passive mode).

Probably due to my own lack of expertise in the area, but I find the explanations and examples (in this section and its sub-sections) not easy to understand.

### Section 7

Perhaps because English is not my primary language, but the title of the section includes "Guidance", i.e., it does not smell normative while it actually is.

The use of a "MUST" with an unless as in `unless the client is known to wait for a 2xx` is rather weird, but perhaps clearer than a "SHOULD" with the same unless...

How can a server check that `the client is known to wait for a 2xx` ? At the bare minimum the text should contain "how it is done is out of scope".

[Ballot comment]
I also agree with Gorry that the abstract wording could be updated to explain the true purpose of the document.

Section 5.3
> A client MAY optimistically start sending UDP packets in HTTP Datagrams before receiving the response to its UDP proxying request, but only if the HTTP version in use is HTTP/2 or later. Clients MUST NOT send UDP packets optimistically in HTTP/1.x due to the risk of request smuggling attacks.

The guidelines for the client are great, but shouldn’t there be a similar requirement for the server. Something along the lines of “If a server receiving UDP packets optimistically in a session that is HTTP/1.1 and has received a Upgrade Request but has not responded to that request, it should drop all the UDP packets received optimistically”.

Something similar should be mentioned in Section 7 for the CONNECT method also.

[Ballot comment]
Thanks to the author and the WG for their work on this document.

I concur with Gorry's comments and observations.

I find it odd that the document does not have an introduction section and that may be a good place to give an overview of what the document does. More importantly, put in there forward references/pointer to the sections 5.3 and 7 - those I believe are the "normative meat" and worthy of drawing attention to up front. Essentially, same as what Gorry said.

[Ballot comment]
Thank you for providing this useful update around linking both the old and new http worlds.

I have two comments for consideration:

1. I *think* the only normaltive change is in section 5.3, to me it would be super-helpful if this was up-front so it cannot be lost.  I wonder if a few sentences in section 1 could tell the reader:
* There is a review of the background and security issues
* Consideration of the impact on HTTP Upgrade with Existing Upgrade Tokens
- including normative changes in section 5.3
* Guidance for future use of upgrade tokens and the use of HTTP CONNECT.


2. In a similar vein, for the abstract:

The current abstract says the document "discusses the security considerations" ..., and "updates RFC 9112 and RFC 9298 to avoid related security issues". That seems true, but I wonder if it is worth saying "updates the requirements in RFC 9112 and RFC 9298 to avoid related security issues". I'd be really sad if someone glanced at the abstract and skipped it thinking it was a security discussion rather than something they needed to action.

[Ballot comment]
Hi Ben,

Thanks for the effort put into this well-written spec.

Please find below some minor comments:

# Please help readers to find where to look for various statements in the spec. For example:

(1)

OLD:
  In HTTP/1.1 and later, a single connection can be used for many
  requests.  In HTTP/2 and HTTP/3, these requests

NEW:
  In HTTP/1.1 [RFC9112]  and later, a single connection can be used for many
  requests.  In HTTP/2 [RFC9113] and HTTP/3 [RFC9114], these requests

(2) Point to where this is specified

CURRENT:
  However, in HTTP/1.1, requests are strictly sequential, and each new   
  request is distinguished implicitly by the closure of the preceding
  request.

(3) Cite 9.3.6 of 9110

CURRENT:
  The other mechanism is the HTTP CONNECT method. 

# Only when accepted

OLD:
  The server replies with a 2xx (Successful)
  response to indicate that the request was accepted and a TCP
  connection was established. 

New:
  If accepted, the server replies with a 2xx (Successful)
  response to indicate that the request was accepted and a TCP
  connection was established. 

# Definitive list or samples?

CURRENT:
  Rejections are common, and can happen for a variety of reasons.  A
  request using Upgrade might be rejected if:

Is this the definite list of conditions under which this can be rejected or these are only examples? Consider making this clear in the text.

The same applies for other similar text in the draft

# An example

CURRENT:
  In some cases, the client might expect that the protocol transition
  ^^^^^^^^^^^^
  will succeed. 

Can an example be provided here for illustration purposes?

# Registered Upgrade Tokens

CURRENT:
  This section describes the impact of this document's considerations
  on some registered upgrade tokens that are believed to be in use at
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 
  the time of writing.

Can we cite https://www.iana.org/assignments/http-upgrade-tokens/http-upgrade-tokens.xhtml?

# Future specifications

CURRENT:
  Future specifications for upgrade tokens should account for the
  security issues discussed here and provide clear guidance on how
  implementations can avoid them.

How this reco will be tracked?

# Consider using {:quote} to tag all the citations in the document.

Cheers,
Med

[Ballot discuss]
# Gunter Van de Velde, RTG AD, comments for draft-ietf-httpbis-optimistic-upgrade-05

# The line numbers used are rendered from IETF idnits tool: https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-httpbis-optimistic-upgrade-05.txt

# Thank you for this document. I found it well written and well structured.

# for your convenience, please find some non-blocking COMMENTS, and one blocking DISCUSS (informational vs standards track)


# DISCUSS
# =======

When looking at the abstract:

13   In HTTP/1.1, the client can request a change to a new protocol on the
14   existing connection.  This document discusses the security
15   considerations that apply to data sent by the client before this
16   request is confirmed, and updates RFC 9112 and RFC 9298 to avoid
17   related security issues.

GV> What I find a little confusing is that the draft doesn’t seem to introduce new procedures or formal normative language, yet it is published on the Standards Track. In the shepherd write-up I noticed the reasoning:

"
Proposed Standard, since this is updating other Proposed Standard documents.
"

If the draft mainly provides context and background rather than procedures, what is the specific mechanism by which it is considered to be “updating” RFC 9112 and RFC 9298? In other words, does it truly update these RFCs in a standards-track sense, or does it serve more as an explanatory security note?

[Ballot comment]
# comments
# ========

112   specified host and port.  The server replies with a 2xx (Successful)
113   response to indicate that the request was accepted and a TCP
114   connection was established.  After this point, the TCP connection is

GV> Do the xx in the above displayed "2xx" have a meaning? I assume tha the "2" means successfull and that the xx is some code on the type of success? is there a reference for these?

190   different origin (party 3).  Post-transition protocols such as
191   WebSocket similarly are often used to convey data chosen by a third
192   party.

GV> Should there be a reference for the WebSocket protocol added?

Thanks again for this wonderful written document.

Kind Regards,
Gunter Van de Velde
RTG Area Director

IESG/Authors/WG Chairs:

IANA has completed its review of draft-ietf-httpbis-optimistic-upgrade-05, which is currently in Last Call, and has the following comments:

We understand that this document doesn't require any registry actions.

While it's often helpful for a document's IANA Considerations section to remain in place upon publication even if there are no actions, if the authors strongly prefer to remove it, we do not object.

If this assessment is not accurate, please respond as soon as possible.

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 2025-09-05):

From: The IESG
To: IETF-Announce
CC: draft-ietf-httpbis-optimistic-upgrade@ietf.org, httpbis-chairs@ietf.org, ietf-http-wg@w3.org, mbishop@evequefou.be, tpauly@apple.com
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (Security Considerations for Optimistic Protocol Transitions in HTTP/1.1) to Proposed Standard


The IESG has received a request from the HTTP WG (httpbis) to consider the
following document: - 'Security Considerations for Optimistic Protocol
Transitions in
  HTTP/1.1'
  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 2025-09-05. 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


  In HTTP/1.1, the client can request a change to a new protocol on the
  existing connection.  This document discusses the security
  considerations that apply to data sent by the client before this
  request is confirmed, and updates RFC 9112 and RFC 9298 to avoid
  related security issues.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-httpbis-optimistic-upgrade/



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?

This document, which highlights some security issues with HTTP/1.1 upgrade
and fixes some bugs in proxying UDP over HTTP, is something that the HTTPBIS
WG supported as a useful and important fix. The WGLC received good and detailed
reviews from around 4 individuals, which isn't a huge number of people; however,
this was discussed at many meetings and did have clear support.

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

No controversy or concerns raised in consensus.

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 appeals threatened or discontent expressed.

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)?

This is not a protocol to implement, per se, but rather a fix to warn people
about what *not* to do.

## 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.

This is very specific to details of using HTTP/1.1 upgrade, particularly with
MASQUE proxying; it doesn't have impact on external organizations or other groups
other than MASQUE (for which the participants were very overlapping — it was
decided to run this document through HTTPBIS because the advice is more general
than just MASQUE, but MASQUE is aware of this work).

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.

No formal types 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][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]?

No YANG.

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.

No formal language.

## Document Shepherd Checks

9. Based on the shepherd's review of the document, is it their opinion that this
  document is needed, clearly written, complete, correctly designed, and ready
  to be handed off to the responsible Area Director?

Yes, I find this document to be clear and complete, and ready to progress.

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 particular areas identified; this is squarely in HTTP, but has received
good WG review from experts there.

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?

Proposed Standard, since this is updating other Proposed Standard documents.

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.

No disclosures have been filed, and authors are aware of their responsibilities.

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 is one author who is willing 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.)

The one nit found is:

"
  -- The draft header indicates that this document updates RFC9112, but the
    abstract doesn't seem to mention this, which it should.
"

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

An argument could be made that the reference to RFC9112 should be normative instead
of Informative; however, I'll let the ADs decide what they prefer here.

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

No non-RFC references

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 normative downward references

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, all references are RFCs.

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.

This document updates RFC 9112 and RFC 9298, but does not change their statuses.
The title page lists this, and RFC 9298 is mentioned in the abstract.

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]).

There are no IANA actions.

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.

There are no IANA actions.

[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.*

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?

This document, which highlights some security issues with HTTP/1.1 upgrade
and fixes some bugs in proxying UDP over HTTP, is something that the HTTPBIS
WG supported as a useful and important fix. The WGLC received good and detailed
reviews from around 4 individuals, which isn't a huge number of people; however,
this was discussed at many meetings and did have clear support.

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

No controversy or concerns raised in consensus.

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 appeals threatened or discontent expressed.

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)?

This is not a protocol to implement, per se, but rather a fix to warn people
about what *not* to do.

## 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.

This is very specific to details of using HTTP/1.1 upgrade, particularly with
MASQUE proxying; it doesn't have impact on external organizations or other groups
other than MASQUE (for which the participants were very overlapping — it was
decided to run this document through HTTPBIS because the advice is more general
than just MASQUE, but MASQUE is aware of this work).

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.

No formal types 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][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]?

No YANG.

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.

No formal language.

## Document Shepherd Checks

9. Based on the shepherd's review of the document, is it their opinion that this
  document is needed, clearly written, complete, correctly designed, and ready
  to be handed off to the responsible Area Director?

Yes, I find this document to be clear and complete, and ready to progress.

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 particular areas identified; this is squarely in HTTP, but has received
good WG review from experts there.

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?

Proposed Standard, since this is updating other Proposed Standard documents.

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.

No disclosures have been filed, and authors are aware of their responsibilities.

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 is one author who is willing 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.)

The one nit found is:

"
  -- The draft header indicates that this document updates RFC9112, but the
    abstract doesn't seem to mention this, which it should.
"

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

An argument could be made that the reference to RFC9112 should be normative instead
of Informative; however, I'll let the ADs decide what they prefer here.

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

No non-RFC references

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 normative downward references

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, all references are RFCs.

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.

This document updates RFC 9112 and RFC 9298, but does not change their statuses.
The title page lists this, and RFC 9298 is mentioned in the abstract.

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]).

There are no IANA actions.

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.

There are no IANA actions.

[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/