A BGP Cease NOTIFICATION Subcode for Bidirectional Forwarding Detection (BFD)
RFC 9384

Received changes through RFC Editor sync (created alias RFC 9384, changed title to 'A BGP Cease NOTIFICATION Subcode for Bidirectional Forwarding Detection (BFD)', changed abstract to 'The Bidirectional Forwarding Detection (BFD) protocol (RFC 5880) is used to detect loss of connectivity between two forwarding engines, typically with low latency. BFD is leveraged by routing protocols, including the Border Gateway Protocol (BGP), to bring down routing protocol connections more quickly than the original protocol timers.

This document defines a subcode for the BGP Cease NOTIFICATION message (Section 6.7 of RFC 4271) for use when a BGP connection is being closed due to a BFD session going down.', changed standardization level to Proposed Standard, changed state to RFC, added RFC published event at 2023-03-24, changed IESG state to RFC Published)

[Ballot comment]
Thank you to Melinda Shore for the SECDIR review.  I concur with both of her points:

-- The Security Considerations would benefit from making a declarative statement that no additional considerations applying beyond those already stated for BFD in RFC5880.

-- Noting that this is an option sub-code in the BFD ecosystem.

[Ballot comment]
Thanks for a simple, straightforward document.

I concur with Eric's remark about the shepherd writeup.

The SHOULD in Section 2 is peculiar.  Why might I not do what it says, which SHOULD allows?  The document should provide some guidance here.  I have the same concern about the SHOULD at the end of Section 3.

The first sentence of the last paragraph of Section 1 and of Section 3 appear to have been mangled.  Please review.  Also, in the final sentence of Section 1, "close" should be "closes".

[Ballot comment]
I briefly considered balloting a "DISCUSS DISCUSS"; I didn't want to discuss the document itself, but rather how do we make it easier to progress documents like this without having to (presumably) burn many hours of people's time (looking in archives, there are >100 emails mentioning this document). Instead of a "DISCUSS DISCUSS", I'll just make a note to bring this up at an informal or workshop or something.

[Ballot comment]
I briefly considered balloting a "DISCUSS DISCUSS"; I didn't want to discuss the document itself, but rather how do we make it easier to progress documents like this without having to (presumably) burn many hours of people's time. Instead of a "DISCUSS DISCUSS", I'll just make a note to bring this up at an informal or workshop.

[Ballot comment]

# Éric Vyncke, INT AD, comments for draft-ietf-idr-bfd-subcode-04

CC @evyncke

Thank you for the work put into this document: it is clear and the intent is useful.

Please find below one nit.

Special thanks to Keyur Patel for the shepherd's detailed write-up including the WG consensus *but* missing the justification of the intended status.

I hope that this review helps to improve the document,

Regards,

-éric

## NITS

### Section 7.2

As detected by the id-nits tools, reference to RFC4486 does not seem to be used.

## Notes

This review is in the ["IETF Comments" Markdown format][ICMF], You can use the
[`ietf-comments` tool][ICT] to automatically convert this review into
individual GitHub issues.

[ICMF]: https://github.com/mnot/ietf-comments/blob/main/format.md
[ICT]: https://github.com/mnot/ietf-comments

[Ballot comment]
Thanks for this short, useful, readable document. I have just a few
comments and nits.

## Comments

### Section 1, hold time of zero doesn't mean zero

                                                                    As
  per Section 4.2 of [RFC4271], the minimum Hold Time interval
  supported by the protocol must be either zero, or at least three
  seconds. 

Since zero is a distinguished value that disables keepalive processing (RFC
4271 §4.4), maybe something like this instead?

                                                                    As
  per Section 4.2 and Section 4.4 of [RFC4271], the minimum Hold Time
  interval is at least three seconds, unless KEEPALIVE processing has
  been disabled by negotiating the distinguished Hold Time of zero.

### Section 2, SHOULD v. MUST

  When a BGP connection is terminated due to a BFD session going into
  the Down state, the BGP speaker SHOULD send a NOTIFICATION message
  with the Error Code Cease and the Error Subcode "BFD Down".

Why isn't it a MUST? If the qualm is over the fact you might not always be
able to send a notification message, perhaps rewrite something like "the
NOTIFICATION message sent by the BGP speaker MUST use Error Code Cease and
Error Subcode 'BFD Down'"? Or "MUST attempt to send", "MUST send if
possible", etc.

### Section 3, this clause no verb

The first clause here is missing a verb:

  When the procedures in [RFC8538] for sending a NOTIFICATION message
  with a Cease Code and Hard Reset Subcode, and the BGP connection is
  being terminated because BFD has gone Down, the BFD Down Subcode
  SHOULD be encapsulated in the Hard Reset's data portion of the
  NOTIFICATION message.

Maybe adding "are in use" would fix it? As in

  When the procedures in [RFC8538] for sending a NOTIFICATION message
  with a Cease Code and Hard Reset Subcode are in use, and the BGP ...
 
### Section 2, SHOULD v. MUST again

In the text quoted in the previous, there's another SHOULD, and again I
wonder why it's not a MUST.

### Section 4, no new security considerations

While I agree that

  This document introduces no additional BGP security considerations.

it might be considerate to explain to the reader why they should believe
that. Up to you, but I might have said something like,

  The new functionality introduced by this document is limited to indicating
  the reason a session is being reset. It is difficult to imagine a way an
  attacker could make use of that information in a harmful way, considering
  that by definition the BGP session in question has already been closed.

## Nits

### Section 1

                                This is typically used by the clients
  to quickly trigger closure of their connections than the native
  protocol timers might allow.
 
Should be "to trigger closure... more quickly than the native". (Add a
"more" and move the "quickly".)

### Section 1

  If a BGP speaker desires to have its connections terminate faster
  than the negotiated BGP Hold Timer can accommodate upon loss of
  connectivity with a neighbor, the BGP speakers can rely upon BFD is
  used to supply that faster detection.
 
I think that last clause should remove the words "the BGP speakers can
rely upon".

### Section 1

                                          When the BFD session state
  changes to Down, the BGP speaker terminates the connection with a
  NOTIFICATION message sent to the neighbor, if possible, and then
  close the TCP connection for the connection.
 
s/close/closes/

[Ballot comment]
Thanks for this short, useful, readable document. I have just a few
comments and nits.

## Comments

### Section 1

                                the minimum Hold Time interval
  supported by the protocol must be either zero, or at least three
  seconds.
 
Might be nice to mention that zero is a distinguished value that
disables keepalive processing (RFC 4271 §4.4).

### Section 2, SHOULD v. MUST

  When a BGP connection is terminated due to a BFD session going into
  the Down state, the BGP speaker SHOULD send a NOTIFICATION message
  with the Error Code Cease and the Error Subcode "BFD Down".

Why ain't it a MUST? If the qualm is over the fact you might not always be
able to send a notification message, perhaps rewrite something like "the
NOTIFICATION message sent by the BGP speaker MUST use Error Code Cease and
Error Subcode 'BFD Down'"? Or "MUST attempt to send", "MUST send if
possible", etc.

### Section 3

The first clause here is missing a verb:

  When the procedures in [RFC8538] for sending a NOTIFICATION message
  with a Cease Code and Hard Reset Subcode, and the BGP connection is
  being terminated because BFD has gone Down, the BFD Down Subcode
  SHOULD be encapsulated in the Hard Reset's data portion of the
  NOTIFICATION message.

Maybe adding "are in use" would fix it? As in

  When the procedures in [RFC8538] for sending a NOTIFICATION message
  with a Cease Code and Hard Reset Subcode are in use, and the BGP ...
 
Also, again how come SHOULD instead of MUST?

### Section 4, no new security considerations

While I agree that

  This document introduces no additional BGP security considerations.

it might be nice to explain to the reader why they should believe that.
Up to you, but I might have said something like,

  The new functionality introduced by this document is limited to indicating
  the reason a session is being reset. It is difficult to imagine a way an
  attacker could make use of that information in a harmful way, considering
  that by definition the BGP session in question has already been closed.

## Nits

### Section 1

                                This is typically used by the clients
  to quickly trigger closure of their connections than the native
  protocol timers might allow.
 
Should be "to trigger closure... more quickly than the native".

### Section 1

  If a BGP speaker desires to have its connections terminate faster
  than the negotiated BGP Hold Timer can accommodate upon loss of
  connectivity with a neighbor, the BGP speakers can rely upon BFD is
  used to supply that faster detection.
 
I think that last clause should remove the words "the BGP speakers can
rely upon".

### Section 1

                                          When the BFD session state
  changes to Down, the BGP speaker terminates the connection with a
  NOTIFICATION message sent to the neighbor, if possible, and then
  close the TCP connection for the connection.
 
s/close/closes/

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

The IANA Functions Operator has completed its review of draft-ietf-idr-bfd-subcode-04. If any part of this review is inaccurate, please let us know.

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

In the BGP Cease NOTIFICATION message subcodes subregistry of the BGP Error Subcodes registry on the Border Gateway Protocol (BGP) Parameters registry page located at:

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

the temporary registration for Value 10 (Name: BFD Down) will be made permanent and its registration changed to [ RFC-to-be ].

The IANA Functions Operator understands that this is the only action required to be completed 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 Specialist

The following Last Call announcement was sent out (ends 2022-11-15):

From: The IESG
To: IETF-Announce
CC: aretana.ietf@gmail.com, draft-ietf-idr-bfd-subcode@ietf.org, idr-chairs@ietf.org, idr@ietf.org, keyur@arrcus.com
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (A BGP Cease Notification Subcode For Bidirectional Forwarding Detection (BFD)) to Proposed Standard


The IESG has received a request from the Inter-Domain Routing WG (idr) to
consider the following document: - 'A BGP Cease Notification Subcode For
Bidirectional Forwarding
  Detection (BFD)'
  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 2022-11-15. 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 Bidirectional Forwarding Detection (BFD) protocol is used to
  detect loss of connectivity between two forwarding engines, typically
  with low latency.  BFD is leveraged by routing protocols, including
  the Border Gateway Protocol (BGP), to bring down routing protocol
  connections faster than the native protocol timers.

  This document defines a Subcode for the BGP Cease NOTIFICATION
  message for when a BGP connection is being closed due to a BFD
  session going down.





The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-idr-bfd-subcode/



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

Call Conclusion email
https://mailarchive.ietf.org/arch/msg/idr/MseVn-JqfSgq8LYkt805SeDLDeI/

# 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?

There is a broad consensus within the WG to progress the document.

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

The draft is very simple and straightforward. There was no controversy about any points and the decision to progress the draft was fairly straightforward.

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 multiple implementations of this draft. They can be found in the implementation report:
https://trac.ietf.org/trac/idr/wiki/draft-ietf-idr-bfd-subcode%20implementations.

## 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 draft defines a new BGP CEASE NOTIFICATION subcode for BFD down event. This subcode is used by BGP to indicate the reason for transitioning its neighbor session to the DOWN/SHUT/IDLE state. Since the subcode is BGP NOTIFICATION message specific, it may not benefit from any cross WG reviews at this point.

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 XML, MIB, Yang, Media type or URI review needed.

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 module present.

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 XML code, BNF rules, MIB definitions, CBOR's CDDL present.

## 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?

This document is fairly simple, clearly written, complete and ready to be handed off to the responsible AD.

10. Several IETF Areas have assembled [lists of common issues that their
    reviewers encounter][6]. For which areas have such issues been identified
    and addressed? For which does this still need to happen in subsequent
    reviews?

N/A.

11. What type of RFC publication is being requested on the IETF stream ([Best
    Current Practice][12], [Proposed Standard, Internet Standard][13],
    [Informational, Experimental or Historic][14])? Why is this the proper type
    of RFC? Do all Datatracker state attributes correctly reflect this intent?

Standards Track.

12. Have reasonable efforts been made to remind all authors of the intellectual
    property rights (IPR) disclosure obligations described in [BCP 79][8]? 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.

There are NO IPRs known at this point for the draft. The draft author is not aware of any IPR related to this document.
https://mailarchive.ietf.org/arch/msg/idr/BAldiVGhh8dRDbbb-Qc6TYwOgjM/


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.

There is only one draft author for this document.

14. Document any remaining I-D nits in this document. Simply running the [idnits
    tool][8] is not enough; please review the ["Content Guidelines" on
    authors.ietf.org][15]. (Also note that the current idnits tool generates
    some incorrect warnings; a rewrite is underway.)

There are no issues reported by idnits at this point:

idnits 2.17.1

draft-ietf-idr-bfd-subcode-03.txt:

  Checking boilerplate required by RFC 5378 and the IETF Trust (see
  https://trustee.ietf.org/license-info):
  ----------------------------------------------------------------------------

    No issues found here.

  Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt:
  ----------------------------------------------------------------------------

    No issues found here.

  Checking nits according to https://www.ietf.org/id-info/checklist :
  ----------------------------------------------------------------------------

    No issues found here.



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

No.

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

None.

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.

None.

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?

None.

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]).

This document has defined a new BGP Cease NOTIFICATION message subcode called "BFD Down". IANA has assigned the value 10 from the BGP Cease NOTIFICATION message subcodes registry with the Name "BFD Down", and a Reference of this 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.

None.

[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://trac.ietf.org/trac/ops/wiki/yang-review-tools
[5]: https://www.rfc-editor.org/rfc/rfc8342.html
[6]: https://trac.ietf.org/trac/iesg/wiki/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/

Call Conclusion email
https://mailarchive.ietf.org/arch/msg/idr/MseVn-JqfSgq8LYkt805SeDLDeI/

# 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?

There is a broad consensus within the WG to progress the document.

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

The draft is very simple and straightforward. There was no controversy about any points and the decision to progress the draft was fairly straightforward.

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 multiple implementations of this draft. They can be found in the implementation report:
https://trac.ietf.org/trac/idr/wiki/draft-ietf-idr-bfd-subcode%20implementations.

## 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 draft defines a new BGP CEASE NOTIFICATION subcode for BFD down event. This subcode is used by BGP to indicate the reason for transitioning its neighbor session to the DOWN/SHUT/IDLE state. Since the subcode is BGP NOTIFICATION message specific, it may not benefit from any cross WG reviews at this point.

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 XML, MIB, Yang, Media type or URI review needed.

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 module present.

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 XML code, BNF rules, MIB definitions, CBOR's CDDL present.

## 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?

This document is fairly simple, clearly written, complete and ready to be handed off to the responsible AD.

10. Several IETF Areas have assembled [lists of common issues that their
    reviewers encounter][6]. For which areas have such issues been identified
    and addressed? For which does this still need to happen in subsequent
    reviews?

N/A.

11. What type of RFC publication is being requested on the IETF stream ([Best
    Current Practice][12], [Proposed Standard, Internet Standard][13],
    [Informational, Experimental or Historic][14])? Why is this the proper type
    of RFC? Do all Datatracker state attributes correctly reflect this intent?

Standards Track.

12. Have reasonable efforts been made to remind all authors of the intellectual
    property rights (IPR) disclosure obligations described in [BCP 79][8]? 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.

There are NO IPRs known at this point for the draft. The draft author is not aware of any IPR related to this document.
https://mailarchive.ietf.org/arch/msg/idr/BAldiVGhh8dRDbbb-Qc6TYwOgjM/


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.

There is only one draft author for this document.

14. Document any remaining I-D nits in this document. Simply running the [idnits
    tool][8] is not enough; please review the ["Content Guidelines" on
    authors.ietf.org][15]. (Also note that the current idnits tool generates
    some incorrect warnings; a rewrite is underway.)

There are no issues reported by idnits at this point:

idnits 2.17.1

draft-ietf-idr-bfd-subcode-03.txt:

  Checking boilerplate required by RFC 5378 and the IETF Trust (see
  https://trustee.ietf.org/license-info):
  ----------------------------------------------------------------------------

    No issues found here.

  Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt:
  ----------------------------------------------------------------------------

    No issues found here.

  Checking nits according to https://www.ietf.org/id-info/checklist :
  ----------------------------------------------------------------------------

    No issues found here.



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

No.

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

None.

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.

None.

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?

None.

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]).

This document has defined a new BGP Cease NOTIFICATION message subcode called "BFD Down". IANA has assigned the value 10 from the BGP Cease NOTIFICATION message subcodes registry with the Name "BFD Down", and a Reference of this 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.

None.

[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://trac.ietf.org/trac/ops/wiki/yang-review-tools
[5]: https://www.rfc-editor.org/rfc/rfc8342.html
[6]: https://trac.ietf.org/trac/iesg/wiki/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/

Call Conclusion email
https://mailarchive.ietf.org/arch/msg/idr/MseVn-JqfSgq8LYkt805SeDLDeI/

# 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?

There is a broad consensus within the WG to progress the document.

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

the draft is very simple and straightforward. There was no controversy about any points and the decision to progress the draft was fairly straightforward.

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 multiple implementations of this draft. They can be found in the implementation report:
https://trac.ietf.org/trac/idr/wiki/draft-ietf-idr-bfd-subcode%20implementations.

## 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 draft defines a new BGP CEASE NOTIFICATION subcode for BFD down event. Since the subcode is BGP NOTIFICATION message specific, it would not benefit from any cross WG reviews at this point.

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 XML, MIB, Yang, Media type or URI review needed.

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 module present.

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 XML code, BNF rules, MIB definitions, CBOR's CDDL present.

## 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?

This document is fairly simple, clearly written, complete and ready to be handed off to the responsible AD.

10. Several IETF Areas have assembled [lists of common issues that their
    reviewers encounter][6]. For which areas have such issues been identified
    and addressed? For which does this still need to happen in subsequent
    reviews?

N/A.

11. What type of RFC publication is being requested on the IETF stream ([Best
    Current Practice][12], [Proposed Standard, Internet Standard][13],
    [Informational, Experimental or Historic][14])? Why is this the proper type
    of RFC? Do all Datatracker state attributes correctly reflect this intent?

Standards Track.

12. Have reasonable efforts been made to remind all authors of the intellectual
    property rights (IPR) disclosure obligations described in [BCP 79][8]? 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.

There are NO IPRs known at this point for the draft. The draft author is not aware of any IPR related to this document.
https://mailarchive.ietf.org/arch/msg/idr/BAldiVGhh8dRDbbb-Qc6TYwOgjM/


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.

There is only one draft author for this document.

14. Document any remaining I-D nits in this document. Simply running the [idnits
    tool][8] is not enough; please review the ["Content Guidelines" on
    authors.ietf.org][15]. (Also note that the current idnits tool generates
    some incorrect warnings; a rewrite is underway.)

There are no issues reported by idnits at this point:

idnits 2.17.1

draft-ietf-idr-bfd-subcode-03.txt:

  Checking boilerplate required by RFC 5378 and the IETF Trust (see
  https://trustee.ietf.org/license-info):
  ----------------------------------------------------------------------------

    No issues found here.

  Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt:
  ----------------------------------------------------------------------------

    No issues found here.

  Checking nits according to https://www.ietf.org/id-info/checklist :
  ----------------------------------------------------------------------------

    No issues found here.



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

NO.

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

None.

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.

None.

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?

None.

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]).

This document has defined a new BGP Cease NOTIFICATION message subcode called "BFD Down". IANA has assigned the value 10 from the BGP Cease NOTIFICATION message subcodes registry with the Name "BFD Down", and a Reference of this 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.

None.

[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://trac.ietf.org/trac/ops/wiki/yang-review-tools
[5]: https://www.rfc-editor.org/rfc/rfc8342.html
[6]: https://trac.ietf.org/trac/iesg/wiki/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/

Call Conclusion email
https://mailarchive.ietf.org/arch/msg/idr/MseVn-JqfSgq8LYkt805SeDLDeI/

# 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?

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

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.)

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)?

## 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.

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.

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]?

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.

## 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?

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?

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?

12. Have reasonable efforts been made to remind all authors of the intellectual
    property rights (IPR) disclosure obligations described in [BCP 79][8]? 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.

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.

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.)

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

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

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?

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.

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]).

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.

[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://trac.ietf.org/trac/ops/wiki/yang-review-tools
[5]: https://www.rfc-editor.org/rfc/rfc8342.html
[6]: https://trac.ietf.org/trac/iesg/wiki/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/