A YANG Data Model for IS-IS Segment Routing over the MPLS Data Plane
draft-ietf-isis-sr-yang-31

[Ballot comment]
Sharing a few comments for consideration in the form of snippets from idnits output for v25:

376     contact
377       "WG Web: 
378         WG List: 
379         Author:    Stephane Litkowski
380                  
381         Author:    Yingzhen Qu
382                  
383         Author:    Acee Lindem
384                  

There seems to be a discrepancy between this text and the author list
;-)

385         Author:    Pushpasis Sarkar
386                  
387         Author:    Ing-Wher Chen
388                  
389         Author:    Jeff Tantsura
390                  
391       ";
392     description
393       "The YANG module defines the generic configuration and
394         operational state for Segment Routing ISIS extensions for the
395         MPLS data plane, which is common across all of the vendor
396         implementations.

"is common across all of the vendor implementations" ... can this
assertion be really made? Suggest to remove this part.

398         This YANG model conforms to the Network Management
399         Datastore Architecture (NMDA) as described in RFC 8342.


533     identity s-flag {
534       base adj-sid-flag;
535       description
536         "Group flag.";

This is called a "set" in ISIS RFC8667

537     }

539     identity pe-flag {

Why not "p-flag"?

540       base adj-sid-flag;
541       description
542         "Persistent flag.";
543     }


564     identity sf-flag {

why not s-flag?

565       base sid-binding-flag;
566       description
567         "S flag. If set, the binding label TLV should be flooded
568           across the entire routing domain.";
569     }


602     grouping sid-sub-tlv {
603       description
604         "SID/Label sub-TLV grouping.";
605       container sid-sub-tlv {
606         description
607           "Used to advertise the SID/Label associated with a
608             prefix or adjacency.";
609         leaf length {
610           type uint8;
611           description
612             "Length of the SID value. YANG model specification
613               is necessary since it dictates the semantics of the
614               SID.";
615         }
616         leaf sid {
617           type uint32;
618           description
619             "Segment Identifier (SID) - A 20 bit label or 32 bit SID.
620               If the length is set to 3, then the 20 rightmost bits
621               represent an MPLS label. If the length is set to 4, then
622               the value is a 32-bit index.";
623         }

Is this going to be extended similar to what was done for OSPF for
consistency?

624       }
625     }


1289 6.  Acknowledgements

1291   Authors would like to thank Derek Yeung, Acee Lindem, Yi Yang for
1292   their major contributions to the draft.  Also thank Reshad Rahman,
1293   and Tom Petch for their thorough reviews and helpful comments.

1295   MITRE has approved this document for Public Release, Distribution
1296   Unlimited, with Public Release Case Number 19-3033.

With the text above (which applies MITRE has some sort of an approval
authority over this document), it seems more appropriate for this author to drop
their MITRE Corporation affiliation.

[Ballot comment]
Section 1, paragraph 0
>    This document defines a YANG data model [RFC7950] that can be used to
>    configure and manage IS-IS Segment Routing [RFC8667] for MPLS data
>    plane and it is an augmentation to the IS-IS YANG data model
>    [RFC9130].

There seems to be some confusion on the use of term "YANG module" and "YANG data model" in this document. A "YANG data model" refers to a collection of YANG modules and submodules that together define a structured representation configuration, operational data, notifications, and RPCs for a given system or protocol, while a "YANG module" refers to a specific YANG file (.yang) defining a set of nodes (container, list, leaf, etc.) that represent configuration or state data. Moreover, a YANG module can be independent and augment other modules.

Based on that definition what you seem to be defining is a YANG module more than a YANG data model. Can that be reflected consistently in this document?

Section 4, paragraph 7
>        This version of this YANG module is part of RFC XXXX
>        (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
>        for full legal notices.

BTW, is there an instruction for the RFC Editor on what to do with RFC XXXX?

Section 4, paragraph 35
>          leaf length {
>            type uint8;
>            description
>              "Length of the SID value. YANG model specification
>              is necessary since it dictates the semantics of the
>              SID.";
>          }
>          leaf sid {
>            type uint32;
>            description
>              "Segment Identifier (SID) - A 20 bit label or 32 bit SID.
>              If the length is set to 3, then the 20 rightmost bits
>              represent an MPLS label. If the length is set to 4, then
>              the value is a 32-bit index.";
>          }
>        }
>      }


I do agree with Med that the definition in YANG for a management attribute does not have to follow the format on the wire. This would be better defined as an explicit type.

Section 4, paragraph 35
>      grouping sr-capability {
>        description
>          "SR capability grouping.";
>        reference
>          "RFC 8667 - IS-IS Extensions for Segment Routing, Section 3";

A grouping makes sense when it is used multiple times in the module. I only see one 'uses' statement for this grouping. If this is true, then this and other single used groupings should be inlined for easier reading of the module.

Section 4, paragraph 34
>          container sr-capability {
>            leaf-list sr-capability-flags {
>              type identityref {
>                base sr-capability;
>              }
>              description
>                "SR Capability sub-TLV flags.";
>            }
>            description
>              "SR Capability Flags.";
>          }

Why a 'container sr-capability' within another 'container sr-capability'? Can this be renamed or removed?

Section 5, paragraph 0
>    The YANG module specified in this document defines a schema for data
>    that is designed to be accessed via network management protocols such
>    as NETCONF [RFC6241] or RESTCONF [RFC8040].  The lowest NETCONF layer
>    is the secure transport layer, and the mandatory-to-implement secure
>    transport is Secure Shell (SSH) [RFC6242].  The lowest RESTCONF layer
>    is HTTPS, and the mandatory-to-implement secure transport is TLS
>    [RFC8446].

Please make sure that this template follows the latest template in rfc8407bis.

No reference entries found for these items, which were mentioned in the text:
[draft-ietf-rtgwg-segment-routing-ti-lfa]

Found IP block or address not inside RFC5737/RFC3849 example ranges: "1.1.1.1".

-------------------------------------------------------------------------------
NIT
-------------------------------------------------------------------------------

All comments below are about very minor potential issues that you may choose to
address in some way - or ignore - as you see fit. Some were flagged by
automated tools (via https://github.com/larseggert/ietf-reviewtool), so there
will likely be some false positives. There is no need to let me know what you
did with these suggestions.

Section 4, paragraph 9
+ s/RFC XXXX/RFC XXXX: A YANG Data Model for IS-IS Segment Routing for the MPLS Data Plane/

Section 3, paragraph 0
>    The figure below describes the overall structure of the isis-sr-mpls
>    YANG module:

s/isis-sr-mpls/ietf-isis-sr-mpls/

Section 4, paragraph 8
>      reference
>        "RFC XXXX";

s/RFC XXXX/RFC XXXX: A YANG Data Model for IS-IS Segment Routing for the MPLS Data Plane/

Section 2, paragraph 1
> iguration parameters that have been setup using the base segment routing modu
>                                    ^^^^^
The verb "set up" is spelled as two words. The noun "setup" is spelled as one.

[Ballot comment]
Thank you to Behcet Sarikaya for the GENART review.

** Per the GENART review and idnits
  == The document doesn't use any RFC 2119 keywords, yet seems to have RFC
    2119 boilerplate text.

** Section 6.
  MITRE has approved this document for Public Release, Distribution
  Unlimited, with Public Release Case Number 19-3033

(Same comment as draft-ietf-ospf-sr-yang-37)

While I appreciate the need to thank those that an author’s time, and that some employers have strict release review requirements, is the above text necessary and can it be removed?  It implies that the named entity has authority to approve the publication of the RFC once the content is in an I-D (which it does not).

[Ballot comment]
# Andy Newton, ART AD, comments for draft-ietf-isis-sr-yang-25
CC @anewton1998

* line numbers:
  - https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-isis-sr-yang-25.txt&submitcheck=True

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

* "Handling Ballot Positions":
  - https://ietf.org/about/groups/iesg/statements/handling-ballot-positions/

## Discuss

## Comments

Thanks for the hard work on this.

## Nits

1263      The ability to disable or enable IS-IS Segment Routing support and/or
1264      change Segment Routing configurations can result in a Denail-of-
1265      Service (DoS) attack, as this may cause traffic to be dropped or

Probably "Denial-of-Service".

[Ballot discuss]
Hi Stéphane, Yingzhen, Pushpasis, Helen, and Jeff,

Thank you for the effort put into this well-written document.

I appreciate your perseverance to push this specification for almost 10 years.

I have a DISCUSS point and a set of comments that I’d like we address. Main comments are tagged with (*).

# DISCUSS

CURRENT:
        leaf length {
          type uint8;
          description
            "Length of the SID value. YANG model specification
              is necessary since it dictates the semantics of the
              SID.";
        }
        leaf sid {
          type uint32;
          description
            "Segment Identifier (SID) - A 20 bit label or 32 bit SID.
              If the length is set to 3, then the 20 rightmost bits
              represent an MPLS label. If the length is set to 4, then
              the value is a 32-bit index.";
        }

This construct mirrors how the object is encoded on the wire, but when it comes to management a type is better instead fo inferring its from the length. I suggest to use an explicit type here instead of an implicit type.

[Ballot comment]
# Abstract

OLD:
  This document defines a YANG data module that can be used to
  configured and manage IS-IS Segment Routing for MPLS data plane.

NEW:
  This document defines a YANG data module that can be used to
  manage IS-IS Segment Routing for MPLS data plane.

Delete “configure” as this is covered by “manage”. Remember the FCAPS ;-)

# Section 2

Clarify this is a device model + Cite where the base model is defined when first cited + avoid restricting the model to configuration. We claim anyway that the module is NMDA compliant.

OLD:
  This document defines a YANG model for IS-IS Segment Routing for the
  MPLS data plane.  It is an augmentation of the IS-IS base model.

  The IS-IS SR MPLS YANG module requires support for the base segment
  routing module [RFC9020], which defines the global segment routing
  configuration independent of any specific routing protocol
  configuration, and support of IS-IS base model [RFC9130] which
  defines basic IS-IS configuration and state.

NEW:
  This document defines a device YANG model for IS-IS Segment Routing for the
  MPLS data plane. It is an augmentation of the IS-IS base model [RFC9130].

  The IS-IS SR MPLS YANG module requires support for the base segment
  routing module [RFC9020], which defines the global SR
  management structure independent of any specific routing protocol,
  and support of IS-IS base model [RFC9130] which
  defines basic IS-IS configuration and state.

# Section 3 (*)

I would split the long tree into small snippets and help readers go through to understand the rationale for each augment.

# Section 4 (*)

I have several comments about the module:

* Please run "pyang -f yang --yang-canonical” as the current order does not follow a canonical order

* Not sure we can claim that the module covers extension that is “which is common across all of the vendors”. I would simply delete that mention.

* The boilerplate is not needed

* It is unfortunate that the naming in the module reasons about TLV objects

* There are missing reference statements

* Need to clarify the mapping with the flags as defined in the base spec (e.g., af-flag/F-flag, sf-flag/S-Flag)

* There are several layers without clear explanation (e.g., sr-capability/sr-capability may question why we need two layers, do we need the tree levels prefix-sid-sub-tlvs/prefix-sid-sub-tlvs/prefix-sid-sub-tlv?)

* No need to repeat the parent prefix

* Use of plural for lists and leaf-list, while singular is recommended in the guidelines.

* There are no reference to justify the default values

* Weird to have “Configuration” while we claim the module is NMDA compliant.

A version that fixes many of these can be found at: https://github.com/boucadair/IETF-Drafts-Reviews/blob/master/YANG/ietf-isis-sr-mpls.yang. Please double check/complete. Thanks.

A diff to track the changes can be seen here: https://github.com/boucadair/IETF-Drafts-Reviews/commit/395b6ece9e7939c33af7d150a71bfd3948bb5ba1

# Section 5

## Please update this section to follow the template defined in 8407bis (*)

## I don’t find “node-msd-tlv” defined in the model

CURRENT:
  Some of the readable data nodes in the modules may be considered
  sensitive or vulnerable in some network environments.  It is thus
  important to control read access (e.g., via get, get-config, or
  notification) to these data nodes.

      /isis:router-capabilities/sr-capability

      /isis:router-capabilities/sr-algorithms

      /isis:router-capabilities/local-blocks

      /isis:router-capabilities/srms-preference

      /isis:router-capabilities/node-msd-tlv

## nit

OLD:
  Unauthorized access to any data node of these subtrees can disclose
  the operational state information of IS-IS protocol on this device.

NEW:
  Unauthorized access to any data node of these subtrees can disclose
  the operational state information of IS-IS protocol on a device.

# Section 7

Consider updating as follows

OLD:
  The IANA is requested to assign one new URI from the IETF XML
  registry ([RFC3688]).  Authors are suggesting the following URI:

          URI: urn:ietf:params:xml:ns:yang:ietf-isis-sr-mpls
          Registrant Contact: The IESG.
          XML: N/A, the requested URI is an XML namespace

  This document also requests one new YANG module name in the YANG
  Module Names registry ([RFC6020]) with the following suggestion :

          name: ietf-isis-sr-mpls
          namespace: urn:ietf:params:xml:ns:yang:ietf-isis-sr-mpls
          prefix: isis-sr-mpls
          reference: RFC XXXX

NEW:
  The IANA is requested to assign a new URI from the IETF XML
  registry [RFC3688]:

          URI: urn:ietf:params:xml:ns:yang:ietf-isis-sr-mpls
          Registrant Contact: The IESG.
          XML: N/A, the requested URI is an XML namespace

  This document also requests a new YANG module name in the YANG
  Module Names registry ([RFC6020]):

          name: ietf-isis-sr-mpls
          namespace: urn:ietf:params:xml:ns:yang:ietf-isis-sr-mpls
          prefix: isis-sr-mpls
          maintained by IANA? N
          reference: RFC XXXX

# References (*)

RFC8446, RFC8340, RFC8040, RFC6242, and RFC6241 are listed as Normative, while they shouldn’t. Please move those to be listed as Informative.

# Appendix A (*)

The JSON example is broken. Please update and validate using yanglint or yangson, for example.

OLD:
  {
    "routing": {
      "router-id": "1.1.1.1",
      "control-plane-protocols": {
        "control-plane-protocol": {
          "type": "isis:isis",
          "name": "isis",
          "isis": {
            "system-id": "1111.2222.3333",
            "interfaces": {
              "interface": {
                "name": "",
                "segment-routing": {
                  "adjacency-sid": {
                    "adj-sids": {
                      "value": 38888
                    }
                  }
                }
              }
            },
            "segment-routing": {
              "enabled": true
            },
            "protocol-srgb": {
              "srgb": {
                "lower-bound": 4000,
                "upper-bound": 5000
              }
            }
          }
        }
      }
    }
  }

NEW:
  {
    "ietf-routing:routing": {
      "router-id": "1.1.1.1",
      "control-plane-protocols": {
        "control-plane-protocol": {
          "type": "ietf-isis:isis",
          "name": "isis",
          "ietf-isis": {
            "system-id": "1111.2222.3333",
            "interfaces": {
              "interface": {
                "name": "",
                "ietf-isis-sr-mpls:segment-routing": {
                  "adjacency-sid": {
                    "adj-sids": {
                      "value": 38888
                    }
                  }
                }
              }
            },
            "ietf-isis-sr-mpls:segment-routing": {
              "enabled": true
            },
            "ietf-isis-sr-mpls:protocol-srgb": {
              "srgb": {
                "lower-bound": 4000,
                "upper-bound": 5000
              }
            }
          }
        }
      }
    }
  }

Cheers,
Med

IESG/Authors/WG Chairs:

IANA has completed its review of draft-ietf-isis-sr-yang-23. If any part of this review is inaccurate, please let us know.

IANA understands that, upon approval of this document, there are two actions which we must complete.

First, in the ns registry on the IETF XML Registry page located at:

https://www.iana.org/assignments/xml-registry/

a new namespace will be registered as follows:

ID: yang:ietf-isis-sr-mpls
URI: urn:ietf:params:xml:ns:yang:ietf-isis-sr-mpls
Filename: [ TBD-at-Registration ]
Reference: [ RFC-to-be ]

As this document requests registrations in a Specification Required (see RFC 8126) registry, we have initiated the required Expert Review via a separate request. Expert review will need to be completed before your document can be approved for publication as an RFC.

Second, in the YANG Module Names registry on the YANG Parameters registry page located at:

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

a new YANG module will be registered as follows:

Name: ietf-isis-sr-mpls
File: [ TBD-at-Registration ]
Maintained by IANA? N
Namespace: urn:ietf:params:xml:ns:yang:ietf-isis-sr-mpls
Prefix: isis-sr-mpls
Module:
Reference: [ RFC-to-be ]

While the YANG module name will be registered after the IESG approves the document, the YANG module file will be posted after the RFC Editor notifies us that the document has been published.

We understand that these are the only actions 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,

Sabrina Tanamal
Lead IANA Services Specialist

The following Last Call announcement was sent out (ends 2025-01-30):

From: The IESG
To: IETF-Announce
CC: Christian Hopps , chopps@chopps.org, draft-ietf-isis-sr-yang@ietf.org, gunter@vandevelde.cc, lsr-chairs@ietf.org, lsr@ietf.org
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (A YANG Data Model for IS-IS Segment Routing for the MPLS Data Plane) to Proposed Standard


The IESG has received a request from the Link State Routing WG (lsr) to
consider the following document: - 'A YANG Data Model for IS-IS Segment
Routing for the MPLS Data Plane'
  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 2025-01-30. 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 defines a YANG data module that can be used to
  configure and manage IS-IS Segment Routing for MPLS data plane.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-isis-sr-yang/



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?

Concurrence of a few experts

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

No

    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)?
N/A

    ## Additional Reviews

    5. Do the contents of this document closely interact with technologies in
      other IETF working groups or external organizations, and would it
      therefore benefit from their review? Have those reviews occurred? If yes,
      describe which reviews took place.

No

    6. Describe how the document meets any required formal expert review
      criteria, such as the MIB Doctor, YANG Doctor, media type, and URI type
      reviews.

YANG doctor review completed

    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]?

Checked, and NMDA yes

    8. Describe reviews and automated checks performed to validate sections of
      the final version of the document written in a formal language, such as
      XML code, BNF rules, MIB definitions, CBOR's CDDL, etc.

N/A

    ## Document Shepherd Checks

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

Yes.

    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.

    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, appropriate as defines standardized yang module.

    12. Have reasonable efforts been made to remind all authors of the
        intellectual property rights (IPR) disclosure obligations described in
        [BCP 79][7]? To the best of your knowledge, have all required
        disclosures been filed? If not, explain why. If yes, summarize any
        relevant discussion, including links to publicly-available messages when
        applicable.

Yes.

    13. Has each author, editor, and contributor shown their willingness to be
        listed as such? If the total number of authors and editors on the front
        page is greater than five, please provide a justification.

Yes.

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

None.

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

May need to move YANG tree and NMDA to informative.

    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.

No.

    18. Are there normative references to documents that are not ready to be
        submitted to the IESG for publication or are otherwise in an unclear
        state? If so, what is the plan for their completion?

No, one ref is submitted to IESG but not yet RFC.

    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]).

Standard YANG update looks good.

    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

# 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?

Concurrence of a few experts

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

No

    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)?
N/A

    ## Additional Reviews

    5. Do the contents of this document closely interact with technologies in
      other IETF working groups or external organizations, and would it
      therefore benefit from their review? Have those reviews occurred? If yes,
      describe which reviews took place.

No

    6. Describe how the document meets any required formal expert review
      criteria, such as the MIB Doctor, YANG Doctor, media type, and URI type
      reviews.

YANG doctor review completed

    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]?

Checked, and NMDA yes

    8. Describe reviews and automated checks performed to validate sections of
      the final version of the document written in a formal language, such as
      XML code, BNF rules, MIB definitions, CBOR's CDDL, etc.

N/A

    ## Document Shepherd Checks

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

Yes.

    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.

    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, appropriate as defines standardized yang module.

    12. Have reasonable efforts been made to remind all authors of the
        intellectual property rights (IPR) disclosure obligations described in
        [BCP 79][7]? To the best of your knowledge, have all required
        disclosures been filed? If not, explain why. If yes, summarize any
        relevant discussion, including links to publicly-available messages when
        applicable.

Yes.

    13. Has each author, editor, and contributor shown their willingness to be
        listed as such? If the total number of authors and editors on the front
        page is greater than five, please provide a justification.

Yes.

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

None.

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

May need to move YANG tree and NMDA to informative.

    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.

No.

    18. Are there normative references to documents that are not ready to be
        submitted to the IESG for publication or are otherwise in an unclear
        state? If so, what is the plan for their completion?

No, one ref is submitted to IESG but not yet RFC.

    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]).

Standard YANG update looks good.

    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

Request for Last Call review by YANGDOCTORS Completed: Ready with Issues. Reviewer: Reshad Rahman. Sent review to list. Submission of review completed at an earlier date.