A YANG Data Model for the RFC 9543 Network Slice Service
draft-ietf-teas-ietf-network-slice-nbi-yang-25

[Ballot comment]
Thanks to the authors for responding to my comments with clarifications. They are all fully addressed.

Thanks to the WG for this good work.

[Ballot comment]
Note that the title, abstract and introduction talk about "RFC 9543 Network Slice Service" but the Security Considerations talk about ietf-network-slice-service. Would it make sense to explain somewhere at the top that an "RFC 9543 Network Slice Service" is the same as an "IETF Network Slice Service" ?

[Ballot comment]
# Internet AD comments for draft-ietf-teas-ietf-network-slice-nbi-yang-22
CC @ekline

* 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/

## Comments

### S6

* If wanted to have a service that was matching on a specific SVLAN + CVLAN
  combination (not just every SVLAN with CVLAN == ), would I use
  both `cvlan-id` and `svlan-id` in the list?

[Ballot comment]

# Éric Vyncke, INT AD, comments for draft-ietf-teas-ietf-network-slice-nbi-yang-23
CC @evyncke

Thank you for the work put into this document.

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

Special thanks to Vishnu Pavan Beeram for the shepherd's write-up including the WG consensus even if the justification of the intended status is rather light.

I hope that this review helps to improve the document,

Regards,

-éric

## COMMENTS (non-blocking)

### IPR on a YANG data model ?

I am just curious and there is no need to reply, but what kind of IPR can be applied to a data model ? Or is about a service ?

### Section 5.1

The model always ties one SLO and one SLE, wouldn't separate templates for SLO & SLE be more granular and more flexible ? E.g., having a SLE template applicable to multiple slices ? or having a SLO without any SLE ? I note that section 5.2.3 has separate data nodes for SLE & SLO.

Should the examples include path-constraints per the tree above ? (I am not a YANG expert though)

"bound" is uint64, i.e., no decimals ? Is it on purpose ?

### Section 5.2

A tree view of the "slice-service" would probably help the reader.

### Section 5.2.1

As figure 7 contains `rw sdp-ip-address*` I would assume that there can be multiple IP addresses so the sentence `The SDP IP address` should include a plural form.

Figure 9 and text, should 'dscp' be all uppercase character (of course the node itself should be lowercase) ?

### Section 6

Thank you for the dual-stack examples for source/destination-ip-prefix :-)

leaf ac-ipv4-prefix-length and leaf ac-ipv6-prefix-length: should there be a range of the values ?

### Section 11.2

Should the IEEE references use a more recent version than 2005 ?

## NITS (non-blocking / cosmetic)

### Section 6

s/Layer 2 or Layer 3/layer-2 or layer-3/

### Use of SVG graphics

To make a much nicer HTML rendering, suggest using the aasvg too to generate SVG graphics. It is worth a try especially if the I-D uses the Kramdown file format ;-)

[Ballot comment]
Section 3, paragraph 5
>    An example of Network Slice Services that contains multiple
>    connectivity constructs is shown in Figure 2.

More of a nit, but since it seems to repeat itself, I would suggest that the document agree on all references to Connectivity Construct and be consistent. I see "Connectivity construct", "connectivity construct", and what I would prefer, "Connectivity Construct" or just "CC". Would suggest putting CC in the terminology section also.

Section 6, paragraph 61
>      typedef percentage {
>        type decimal64 {
>          fraction-digits 5;
>          range "0..100";
>        }
>        description
>          "Percentage to 5 decimal places.";
>      }

Curious to know whether there is a requirement to measure bandwidth down to a percentage value to 5 decimal places? Suffice it to say that this is the first time I am seeing percentage calculation to that precision.

Section 6, paragraph 67
>          leaf-list security {
>            type identityref {
>              base service-security-type;
>            }
>            description
>              "The security functions that the customer requests
>              the operator to apply to traffic between the two SDPs.";
>          }

Why is this a leaf-list? How would one implement more than one security between two SDPs at the same time?

Section 6, paragraph 72
>              leaf ce-mode {
>                type boolean;
>                description
>                  "Indicates that SDP is on the CE.";
>              }

As what? Meaning, does it mean CE when it is set to 'true'? It would help to say that.

Section 6, paragraph 71
>                  leaf ac-ipv4-prefix-length {
>                    type uint8;
>                    description
>                      "The IPv4 subnet prefix length expressed in bits.";
>                  }
>                  leaf ac-ipv6-address {
>                    type inet:ipv6-address;
>                    description
>                      "The IPv6 address of the AC.";
>                  }
>                  leaf ac-ipv6-prefix-length {
>                    type uint8;
>                    description
>                      "The IPv6 subnet prefix length expressed in bits.";
>                  }

Is there a reason why the 'ip-prefix' definition in RFC 6991 cannot be used instead of defining a prefix for IPv4, and one for IPv6?

Section 6, paragraph 70
>              container sdp-monitoring {
>                config false;
>                description
>                  "Container for SDP monitoring metrics.";
>                leaf incoming-bw-value {
>                  type yang:gauge64;
>                  units "bps";
>                  description
>                    "Indicates the absolute value of the incoming
>                    bandwidth at an SDP from the customer network or
>                    from another provider's network.";
>                }
>                leaf incoming-bw-percent {
>                  type percentage;
>                  units "percent";
>                  description
>                    "Indicates a percentage of the incoming bandwidth
>                    at an SDP from the customer network or
>                    from another provider's network.";
>                }
>                leaf outgoing-bw-value {
>                  type yang:gauge64;
>                  units "bps";
>                  description
>                    "Indicates the absolute value of the outgoing
>                    bandwidth at an SDP towards the customer network or
>                    towards another provider's network.";
>                }
>                leaf outgoing-bw-percent {
>                  type percentage;
>                  units "percent";
>                  description
>                    "Indicates a percentage of the outgoing bandwidth
>                    at an SDP towards the customer network or towards
>                    another provider's network.";
>                }
>              }
>            }
>          }

Is there other monitoring information that this model could expose? For example, you are applying QoS on the input and output. What about packets that are dropped because of the QoS policy applied on the input or output?

"B.1.", paragraph 8
>    Figure 20 shows an example YANG JSON data for the body of the Network
>    Slice Service instances request.

These examples are not tagged with and tags to enable them to be extracted. Can these examples be tagged? I was hoping to verify these examples against the model.

DOWNREF [RFC9543] from this Proposed Standard to Informational RFC9543. (For
IESG discussion. It seems this DOWNREF was not mentioned in the Last Call and
also seems to not appear in the DOWNREF registry.)

DOWNREF [I-D.ietf-teas-rfc8776-update] from this Proposed Standard to
draft-ietf-teas-RFC8776-update of unknown standards level. (For IESG
discussion. It seems this DOWNREF was not mentioned in the Last Call and also
seems to not appear in the DOWNREF registry.)

Found terminology that should be reviewed for inclusivity; see
https://www.rfc-editor.org/part2/#inclusive_language for background and more
guidance:

* Term "natively"; alternatives might be "built-in", "fundamental",
  "ingrained", "intrinsic", "original"

-------------------------------------------------------------------------------
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 3, paragraph 5
>      CC: Connectivity construct

s/Connectivity construct/Connectivity Construct/

Section 3, paragraph 4
>    ----: Represents connectivity construct

s/connectivity construct/Connectivity Construct/

Section 2, paragraph 1
> 543]. * Customer Higher-level Operation System: See Section 6.3.1 of [RFC954
>                              ^^^^^^^^^^^^^^^^
The word "operation" doesn't fit in this context. Would it be better to say "Management System"?

Section 4, paragraph 1
> y the customer's higher level operation system to communicate with an NSC fo
>                              ^^^^^^^^^^^^^^^^
The word "operation" doesn't fit in this context. Same suggestion as above for this and more occurances in the document.

Section 5.2, paragraph 4
>  the Network Slice Service. * "geo-location": Indicates SDP location informa
>                                ^^^^^^^^^^^^
This word is normally spelled as one.

Section 6, paragraph 3
> n the bandwidth that can be shared amongst a group of connectivity constructs
>                                    ^^^^^^^
Do not mix variants of the same word ("amongst" and "among") within a single
text.

Section 6, paragraph 24
> ement, if the percentile is set to 95.000 and the 95th percentile one-way de
>                                    ^^^^^^
In English-speaking countries, the correct thousands separator is a comma.

"B.3.", paragraph 7
> o specify a specific SDP belonging to an Network Slice Service. Authors' Addr
>                                      ^^
Use "a" instead of "an" if the following word doesn't start with a vowel sound,
e.g. "a sentence", "a university".

[Ballot comment]
Many thanks to Mike Ounsworth for his secdir review.

I have one small comment:

Section 7, para 2:  Please replace the last sentence with "The YANG-based management protocols have to use a secure transport layer such as SSH [RFC4252], TLS [RFC8446], or QUIC [RFC9000].  The YANG-based management protocols also have to use mutual authentication." [note:  this change will eventually be in the template.]

[Ballot discuss]
I have just one observation that probably should be easy to address, if it turns out to be a problem.

Section 6, paragraph 71
>      grouping connectivity-construct-monitoring-metrics {
>        description
>          "Grouping for connectivity construct monitoring metrics.";
>        uses
>          te-packet-types:one-way-performance-metrics-gauge-packet;
>        uses
>          te-packet-types:two-way-performance-metrics-gauge-packet;
>      }

I know the YANG Validator gave a green chit to this module. However, I am seeing this error when I try to compile the module:

ietf-network-slice-service@2025-02-06.yang:864: error: grouping "one-way-performance-metrics-gauge-packet" not found in module "ietf-te-packet-types"
ietf-network-slice-service@2025-02-06.yang:866: error: grouping "two-way-performance-metrics-gauge-packet" not found in module "ietf-te-packet-types"

If I go to RFC 8776, I see a grouping called 'one-way-performance-metrics-packet', but I do not see a grouping by the name referenced above. What am I missing?

[Ballot comment]
Section 3, paragraph 5
>    An example of Network Slice Services that contains multiple
>    connectivity constructs is shown in Figure 2.

More of a nit, but since it seems to repeat itself, I would suggest that the document agree on all references to Connectivity Construct and be consistent. I see "Connectivity construct", "connectivity construct", and what I would prefer, "Connectivity Construct" or just "CC". Would suggest putting CC in the terminology section also.

Section 6, paragraph 61
>      typedef percentage {
>        type decimal64 {
>          fraction-digits 5;
>          range "0..100";
>        }
>        description
>          "Percentage to 5 decimal places.";
>      }

Curious to know whether there is a requirement to measure bandwidth down to a percentage value to 5 decimal places? Suffice it to say that this is the first time I am seeing percentage calculation to that precision.

Section 6, paragraph 67
>          leaf-list security {
>            type identityref {
>              base service-security-type;
>            }
>            description
>              "The security functions that the customer requests
>              the operator to apply to traffic between the two SDPs.";
>          }

Why is this a leaf-list? How would one implement more than one security between two SDPs at the same time?

Section 6, paragraph 72
>              leaf ce-mode {
>                type boolean;
>                description
>                  "Indicates that SDP is on the CE.";
>              }

As what? Meaning, does it mean CE when it is set to 'true'? It would help to say that.

Section 6, paragraph 71
>                  leaf ac-ipv4-prefix-length {
>                    type uint8;
>                    description
>                      "The IPv4 subnet prefix length expressed in bits.";
>                  }
>                  leaf ac-ipv6-address {
>                    type inet:ipv6-address;
>                    description
>                      "The IPv6 address of the AC.";
>                  }
>                  leaf ac-ipv6-prefix-length {
>                    type uint8;
>                    description
>                      "The IPv6 subnet prefix length expressed in bits.";
>                  }

Is there a reason why the 'ip-prefix' definition in RFC 6991 cannot be used instead of defining a prefix for IPv4, and one for IPv6?

Section 6, paragraph 70
>              container sdp-monitoring {
>                config false;
>                description
>                  "Container for SDP monitoring metrics.";
>                leaf incoming-bw-value {
>                  type yang:gauge64;
>                  units "bps";
>                  description
>                    "Indicates the absolute value of the incoming
>                    bandwidth at an SDP from the customer network or
>                    from another provider's network.";
>                }
>                leaf incoming-bw-percent {
>                  type percentage;
>                  units "percent";
>                  description
>                    "Indicates a percentage of the incoming bandwidth
>                    at an SDP from the customer network or
>                    from another provider's network.";
>                }
>                leaf outgoing-bw-value {
>                  type yang:gauge64;
>                  units "bps";
>                  description
>                    "Indicates the absolute value of the outgoing
>                    bandwidth at an SDP towards the customer network or
>                    towards another provider's network.";
>                }
>                leaf outgoing-bw-percent {
>                  type percentage;
>                  units "percent";
>                  description
>                    "Indicates a percentage of the outgoing bandwidth
>                    at an SDP towards the customer network or towards
>                    another provider's network.";
>                }
>              }
>            }
>          }

Is there other monitoring information that this model could expose? For example, you are applying QoS on the input and output. What about packets that are dropped because of the QoS policy applied on the input or output?

"B.1.", paragraph 8
>    Figure 20 shows an example YANG JSON data for the body of the Network
>    Slice Service instances request.

These examples are not tagged with and tags to enable them to be extracted. Can these examples be tagged? I was hoping to verify these examples against the model.

The IANA review of this document seems to not have concluded yet.

DOWNREF [RFC9543] from this Proposed Standard to Informational RFC9543. (For
IESG discussion. It seems this DOWNREF was not mentioned in the Last Call and
also seems to not appear in the DOWNREF registry.)

DOWNREF [I-D.ietf-teas-rfc8776-update] from this Proposed Standard to
draft-ietf-teas-RFC8776-update of unknown standards level. (For IESG
discussion. It seems this DOWNREF was not mentioned in the Last Call and also
seems to not appear in the DOWNREF registry.)

Found terminology that should be reviewed for inclusivity; see
https://www.rfc-editor.org/part2/#inclusive_language for background and more
guidance:

* Term "natively"; alternatives might be "built-in", "fundamental",
  "ingrained", "intrinsic", "original"

-------------------------------------------------------------------------------
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 3, paragraph 5
>      CC: Connectivity construct

s/Connectivity construct/Connectivity Construct/

Section 3, paragraph 4
>    ----: Represents connectivity construct

s/connectivity construct/Connectivity Construct/

Section 2, paragraph 1
> 543]. * Customer Higher-level Operation System: See Section 6.3.1 of [RFC954
>                              ^^^^^^^^^^^^^^^^
The word "operation" doesn't fit in this context. Would it be better to say "Management System"?

Section 4, paragraph 1
> y the customer's higher level operation system to communicate with an NSC fo
>                              ^^^^^^^^^^^^^^^^
The word "operation" doesn't fit in this context. Same suggestion as above for this and more occurances in the document.

Section 5.2, paragraph 4
>  the Network Slice Service. * "geo-location": Indicates SDP location informa
>                                ^^^^^^^^^^^^
This word is normally spelled as one.

Section 6, paragraph 3
> n the bandwidth that can be shared amongst a group of connectivity constructs
>                                    ^^^^^^^
Do not mix variants of the same word ("amongst" and "among") within a single
text.

Section 6, paragraph 24
> ement, if the percentile is set to 95.000 and the 95th percentile one-way de
>                                    ^^^^^^
In English-speaking countries, the correct thousands separator is a comma.

"B.3.", paragraph 7
> o specify a specific SDP belonging to an Network Slice Service. Authors' Addr
>                                      ^^
Use "a" instead of "an" if the following word doesn't start with a vowel sound,
e.g. "a sentence", "a university".

[Ballot comment]
The list of acronyms is useful, but several of these are domain-specific terms for which the expansion doesn't necessarily help an unfamiliar reader. I wonder if any of these could be augmented with definitions and/or references. Perhaps the list could even be combined with the Terminology section, defining each term and providing an abbreviation where one is commonly used.

The term "IETF Network Slice" (as opposed to "Network Slice" or "RFC 9543 Network Slice") occurs only once in the document other than in the title of draft-ietf-teas-ietf-network-slice-use-cases. I'm unclear what value using "IETF" as a modifier brings here.

[Ballot comment]
Please find a couple of comments below (one of them inline in the idnits output for v22 of the document):

< major > I could not find the construct of co-routed bidirectional connectivity construct in the document. Has it been covered indirectly or have I missed it?


444               Figure 5: Slo Sle Templates Subtree Structure

Slo Sle should be capitalized?

[Ballot comment]
Please find below a couple of comments below (one of them inline in the idnits for v22 of the document):

< major > I could not find the construct of co-routed bidirectional connectivity construct in the document. Has it been covered indirectly or have I missed it?


444               Figure 5: Slo Sle Templates Subtree Structure

Slo Sle should be capitalized?

[Ballot comment]
Thanks for providing a list of common acronyms!

I have some minor comments from reading the current version:

The text says: “When an IETF Network Slice spans multiple administrative domains, the
  'test-only' mode relies on the NSC to aggregate and validate
  information across these domains.”
-  Is this the term defined in RFC 9543? (Maybe a specific reference here could be helpful?).

A few NiTs:
/in[I-D.ietf-teas-actn-vn-yang]/  (there is a missing space before the reference).
/but an example could be it is the management interface of the device./but, for example, this could be the management interface of the device./

- In just a few places you use the word “we”, which might be better reworded to avoid any suggestion this is a personal view of the editor, e.g., / In this document, we simply use the term "Network Slice Service" to refer to this concept./ Thus document uses the term "Network Slice Service" to refer to this concept./
/In other examples, we may choose to eliminate it.  /In other examples, this term is eliminated./
/We are introducing the "peer-sap-id" in this example, /This example introduces the "peer-sap-id”/

[Ballot comment]
Hi Bo, Dhruv, Reza, Tarek, and John,

Thank you for the effort put into this important piece of work. Special thanks to Bo for her patience and dedication to push this forward.

I reviewed this specification several times in the past and all my comments were adequately addressed.

The document has a normative dependency on I-D.ietf-teas-rfc8776-update, which I hope publication will be requested for soon.

Cheers,
Med

IESG/Authors/WG Chairs:

IANA has completed its review of draft-ietf-teas-ietf-network-slice-nbi-yang-17. 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 in the IETF XML Registry group located at:

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

a single new namespace will be registered as follows:

ID: yang:ietf-network-slice-service
URI: urn:ietf:params:xml:ns:yang:ietf-network-slice-service
Filename: [ TBD-at-Registration ]
Reference: [ RFC-to-be ]

As this document requests a registration in an Expert Review or Specification Required (see RFC 8126) registry, we have completed the required Expert Review via a separate request.

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

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

a single new YANG module will be registered as follows:

Name: ietf-network-slice-service
File: [ TBD-at-Registration ]
Maintained by IANA? N
Namespace: urn:ietf:params:xml:ns:yang:ietf-network-slice-service
Prefix: ietf-nss
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,

David Dong
IANA Services Sr. Specialist

The following Last Call announcement was sent out (ends 2025-01-10):

From: The IESG
To: IETF-Announce
CC: draft-ietf-teas-ietf-network-slice-nbi-yang@ietf.org, james.n.guichard@futurewei.com, teas-chairs@ietf.org, teas@ietf.org, vbeeram@juniper.net
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (A YANG Data Model for the RFC 9543 Network Slice Service) to Proposed Standard


The IESG has received a request from the Traffic Engineering Architecture and
Signaling WG (teas) to consider the following document: - 'A YANG Data Model
for the RFC 9543 Network Slice Service'
  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 2025-01-10. Exceptionally, comments may
be sent to iesg@ietf.org instead. In either case, please retain the beginning
of the Subject line to allow automated sorting.

Abstract


  This document defines a YANG data model for RFC 9543 Network Slice
  Service.  The model can be used in the Network Slice Service
  interface between a customer and a provider that offers RFC 9543
  Network Slice Services.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-teas-ietf-network-slice-nbi-yang/


The following IPR Declarations may be related to this I-D:

  https://datatracker.ietf.org/ipr/5662/



The document contains these normative downward references.
See RFC 3967 for additional information:
    rfc9543: A Framework for Network Slices in Networks Built from IETF Technologies (Informational - Internet Engineering Task Force (IETF) stream)
    draft-ietf-teas-rfc8776-update: Common YANG Data Types for Traffic Engineering (None - Internet Engineering Task Force (IETF) stream)

# 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?

“Strong concurrence of a few individuals, with others being silent" is a reasonable
characterization.

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

There was no controversy. There were no 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.)

No one has threatened an appeal. No one has indicated extreme discontent.

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 document provides a YANG data model for RFC 9543 Network Slice Service. 
The document does not include any implementation report. This document is driven 
by multiple vendors and is expected to be implemented in some form.

## 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.

The data model provided in this document uses types defined in modules
produced by OPSAWG. However, there isn’t sufficient dependency to warrant
a review from OPSAWG. The TEAS WG has also sent a liaison to  3GPP-TSGSA-SA2,
3GPP-TSGSA-SA3, 3GPP-TSG-SA-WG5 and O3GPPTSGRAN3, informing them about the
progress of this document. No formal feedback has been received on this 
document from these SDOs.

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.

The document has been reviewed by a YANG Doctor. Please refer to
https://datatracker.ietf.org/doc/review-ietf-teas-ietf-network-slice-nbi-yang-03-yangdoctors-early-lhotka-2023-02-24/

The document has also been reviewed by the Routing Directorate. Please refer to 
https://datatracker.ietf.org/doc/review-ietf-teas-ietf-network-slice-nbi-yang-12-rtgdir-early-retana-2024-05-06/

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]?

Yes, the current version of the YANG module has been checked with recommended
validation tools. Please refer to the YANG validation results on datatracker:
https://datatracker.ietf.org/doc/draft-ietf-teas-ietf-network-slice-nbi-yang/
There are currently 0 errors and 0 warnings listed against the YANG module. 

The YANG module complies with the Network Management Datastore Architecture 
(NMDA) as specified in [RFC 8342]

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

The YANG code in the document has been validated using prescribed YANG review
Tools. The document has been reviewed by a YANG Doctor. 

## 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, it is the shepherd's opinion that the document is needed, reasonably well
written, complete 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?

It is the shepherd's opinion that the document sufficiently addresses all
the issues specified in [6].

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?

The type of publication being requested is "Standards Track". This is appropriate
for a document that provides a YANG data model for RFC 9543 Network Slice Service.
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][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.

The TEAS WG conducts an IPR poll before an individual draft becomes a WG document
and before a WG document goes to last call. The WG process requires IPR compliance
statement from all authors and contributors listed in the document. This process
was duly applied to the document. There is an IPR disclosure associated with this
document: https://datatracker.ietf.org/ipr/5662/

Pre-WGLC IPR Poll: Please refer to entries dated 2024-04-11 and 2024-04-12 at
https://datatracker.ietf.org/doc/draft-ietf-teas-ietf-network-slice-nbi-yang/history/

Pre-WG-Adoption IPR Poll: Please refer to entry dated 2021-08-27 at
https://datatracker.ietf.org/doc/draft-wd-teas-ietf-network-slice-nbi-yang/history/


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.

The authors/editors and contributors have had sufficient opportunities to express
unwillingness to be listed as such. There are 5 authors listed on the front page 
and 2 other contributors listed later in the 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 I-D nits listed against this document:
https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-teas-ietf-network-slice-nbi-yang-16.txt

Summary: 1 error (**), 0 flaws (~~), 8 warnings (==).

Error: Downref: Normative reference to an Informational RFC: RFC 9543.
The normative reference is appropriate since the components of the YANG model are
defined in the framework discussed in RFC 9543.

Warnings: The 6 “weird spacing” warnings can be ignored and 2 “outdated reference”
warnings can be addressed during the “AD Review” phase.

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

All listed informative and normative references are appropriate.

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

All listed normative references are freely available.

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.

Yes. There is a normative reference to an Informational RFC (RFC 9543). The normative
reference is appropriate since the components of the YANG model are defined in the
framework discussed in RFC 9543.

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?

Yes. There is a normative reference to draft-ietf-teas-rfc8776-update, for which
publication request has not been submitted yet. draft-ietf-teas-rfc8776-update
has completed WGLC and is getting ready to be submitted for publication.

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.

The publication of this document will not change the status of any existing RFCs.

20. Describe the document shepherd's review of the IANA considerations section,
    especially with regard to its consistency with the body of the document.
    Confirm that all aspects of the document requiring IANA assignments are
    associated with the appropriate reservations in IANA registries. Confirm
    that any referenced IANA registries have been clearly identified. Confirm
    that each newly created IANA registry specifies its initial contents,
    allocations procedures, and a reasonable name (see [RFC 8126][11]).

The allocation requests made to the IANA in this document are appropriate
and the referenced IANA registries are clearly identified. There are no new 
IANA registries proposed in 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.

There are no new IANA registries proposed in this document.

[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?

“Strong concurrence of a few individuals, with others being silent" is a reasonable
characterization.

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

There was no controversy. There were no 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.)

No one has threatened an appeal. No one has indicated extreme discontent.

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 document provides a YANG data model for RFC 9543 Network Slice Service. 
The document does not include any implementation report. This document is driven 
by multiple vendors and is expected to be implemented in some form.

## 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.

The data model provided in this document uses types defined in modules
produced by OPSAWG. However, there isn’t sufficient dependency to warrant
a review from OPSAWG. The TEAS WG has also sent a liaison to  3GPP-TSGSA-SA2,
3GPP-TSGSA-SA3, 3GPP-TSG-SA-WG5 and O3GPPTSGRAN3, informing them about the
progress of this document. No formal feedback has been received on this 
document from these SDOs.

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.

The document has been reviewed by a YANG Doctor. Please refer to
https://datatracker.ietf.org/doc/review-ietf-teas-ietf-network-slice-nbi-yang-03-yangdoctors-early-lhotka-2023-02-24/

The document has also been reviewed by the Routing Directorate. Please refer to 
https://datatracker.ietf.org/doc/review-ietf-teas-ietf-network-slice-nbi-yang-12-rtgdir-early-retana-2024-05-06/

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]?

Yes, the current version of the YANG module has been checked with recommended
validation tools. Please refer to the YANG validation results on datatracker:
https://datatracker.ietf.org/doc/draft-ietf-teas-ietf-network-slice-nbi-yang/
There are currently 0 errors and 0 warnings listed against the YANG module. 

The YANG module complies with the Network Management Datastore Architecture 
(NMDA) as specified in [RFC 8342]

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

The YANG code in the document has been validated using prescribed YANG review
Tools. The document has been reviewed by a YANG Doctor. 

## 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, it is the shepherd's opinion that the document is needed, reasonably well
written, complete 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?

It is the shepherd's opinion that the document sufficiently addresses all
the issues specified in [6].

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?

The type of publication being requested is "Standards Track". This is appropriate
for a document that provides a YANG data model for RFC 9543 Network Slice Service.
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][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.

The TEAS WG conducts an IPR poll before an individual draft becomes a WG document
and before a WG document goes to last call. The WG process requires IPR compliance
statement from all authors and contributors listed in the document. This process
was duly applied to the document. There is an IPR disclosure associated with this
document: https://datatracker.ietf.org/ipr/5662/

Pre-WGLC IPR Poll: Please refer to entries dated 2024-04-11 and 2024-04-12 at
https://datatracker.ietf.org/doc/draft-ietf-teas-ietf-network-slice-nbi-yang/history/

Pre-WG-Adoption IPR Poll: Please refer to entry dated 2021-08-27 at
https://datatracker.ietf.org/doc/draft-wd-teas-ietf-network-slice-nbi-yang/history/


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.

The authors/editors and contributors have had sufficient opportunities to express
unwillingness to be listed as such. There are 5 authors listed on the front page 
and 2 other contributors listed later in the 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 I-D nits listed against this document:
https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-teas-ietf-network-slice-nbi-yang-16.txt

Summary: 1 error (**), 0 flaws (~~), 8 warnings (==).

Error: Downref: Normative reference to an Informational RFC: RFC 9543.
The normative reference is appropriate since the components of the YANG model are
defined in the framework discussed in RFC 9543.

Warnings: The 6 “weird spacing” warnings can be ignored and 2 “outdated reference”
warnings can be addressed during the “AD Review” phase.

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

All listed informative and normative references are appropriate.

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

All listed normative references are freely available.

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.

Yes. There is a normative reference to an Informational RFC (RFC 9543). The normative
reference is appropriate since the components of the YANG model are defined in the
framework discussed in RFC 9543.

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?

Yes. There is a normative reference to draft-ietf-teas-rfc8776-update, for which
publication request has not been submitted yet. draft-ietf-teas-rfc8776-update
has completed WGLC and is getting ready to be submitted for publication.

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.

The publication of this document will not change the status of any existing RFCs.

20. Describe the document shepherd's review of the IANA considerations section,
    especially with regard to its consistency with the body of the document.
    Confirm that all aspects of the document requiring IANA assignments are
    associated with the appropriate reservations in IANA registries. Confirm
    that any referenced IANA registries have been clearly identified. Confirm
    that each newly created IANA registry specifies its initial contents,
    allocations procedures, and a reasonable name (see [RFC 8126][11]).

The allocation requests made to the IANA in this document are appropriate
and the referenced IANA registries are clearly identified. There are no new 
IANA registries proposed in 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.

There are no new IANA registries proposed in this document.

[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/

Pre WGLC IPR Poll Responses - Part 1

Poll Thread: https://mailarchive.ietf.org/arch/msg/teas/-bDLGPpUp0UdWP7Ucc8Q4qnIT7A/

"Wubo (lana)"
https://mailarchive.ietf.org/arch/msg/teas/pzCu9rBP1h-jsnj7VBebYuDz_Lw/

Dhruv Dhody
https://mailarchive.ietf.org/arch/msg/teas/TFvxMLPpJ0LVxGW2yEtEofh04wU/

"Rokui, Reza"
https://mailarchive.ietf.org/arch/msg/teas/rVPMrzzHkCs2oHBfvkznfVosEgI/

"Tarek Saad (tsaad)"
https://mailarchive.ietf.org/arch/msg/teas/NDHR_xx-6Qik4rgZTHcR8Q-IvwU/

jmullool@cisco.com
https://mailarchive.ietf.org/arch/msg/teas/v6zS80rEpg0LJQ69_LQj3UtQr60/

LUIS MIGUEL CONTRERAS MURILLO
https://mailarchive.ietf.org/arch/msg/teas/yaCwkb7l8y8YUOJejKR0bkPTEeE/

Missing Responses:
hanliuyan@chinamobile.com

Request for posting confirmation emailed to previous authors: Bo Wu , Dhruv Dhody , John Mullooly , Liuyan Han , Reza Rokui , Tarek Saad , teas-chairs@ietf.org