Deterministic Networking (DetNet) YANG Model
draft-ietf-detnet-yang-20

[Ballot comment]
I have no comments, exept a note to Erik Kline's ballot comment :)

IPsec SPI is defined in RFC 4303:

  The set of SPI values in the range 1 through 255 are reserved by the
  Internet Assigned Numbers Authority (IANA) for future use; a reserved
  SPI value will not normally be assigned by IANA unless the use of the
  assigned SPI value is specified in an RFC.  The SPI value of zero (0)
  is reserved for local, implementation-specific use and MUST NOT be
  sent on the wire.

So the definition is probably right. While right now there is no valid SPI < 256,
and some implementations use it to refer to internal things, in theory these
could appear in the future.

[Ballot comment]

# Éric Vyncke, INT AD, comments for draft-ietf-detnet-yang-19

Thank you for the work put into this document.

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

Special thanks to János Farkas for the shepherd's detailed write-up (using the old template) including the WG consensus and a simple but present justification of the intended status.

Please note that Jean-Michel Combes is the Internet directorate reviewer (at my request) and you may want to consider this int-dir review as well when it will be available (no need to wait for it though):
https://datatracker.ietf.org/doc/draft-ietf-detnet-yang/reviewrequest/18768//

I hope that this review helps to improve the document,

Regards,

-éric


# COMMENTS (non-blocking)

## Section 7

The following points may be purist or even pedantic, but here they are:

### Circular references

'traffic-profile' includes leaves such as 'member-app' and 'app-flow' has a leaf 'traffic-profile'. This can lead to *inconsistency* if the values are not compatible. Do YANG/netconf have functions to retrieve which 'app-flow' use 'traffic-profile' ?

Or did I miss something ?

### Leaves names

Why the leaves under 'traffic-profile' are named 'member-app', 'member-fwd-sublayer' rather than 'member-app-flows' and 'member-forwarding' to match the naming used elsewhere ?

## IPv6 in the YANG module

I am uneasy with the model of an IPv6 flow

### inet:ip-address-no-zone

The use of inet:ip-address-no-zone is fine when purely matching on an IPv6 packet, but this also means that link-local addresses cannot be used probably. Is it on purpose ?

### protocol-next-header

```
      description
        "Internet Protocol number.  Refers to the protocol of the
        payload.  In IPv6, this field is known as 'next-header',
        and if extension headers are present, the protocol is
        present in the 'upper-layer' header.";
```

This description is rather vague... It should be really specific when using IPv4. For IPv6 with extension headers, there is no protocol in 'upper-layer' header.

## Section 13.2

Reference IEEE8021QCX is marked as 'superseded' since 2022 at https://ieeexplore.ieee.org/document/9212765 apparently by https://ieeexplore.ieee.org/document/10004498.

## Appendix B

Thank you for using IPv6 examples and very nice SVG diagrams.

Albeit using flows 2001:db8::1/128 <-> 2001:db8::8/128 seems a little unrealistic as both nodes are probably in the same layer-2 link. But, DTN also work on a layer-2 link w/o actual layer-3 routing. Same for the IPv4 examples.

You may also want to refresh the dates to 2024 rather than 2020 ;-

Having some examples is really a good thing, I am just slighlty concerned by the large amount of them in this document. It is a matter of taste, so no need to reply.

[Ballot comment]
** Section 10.  Per the write operations:

-- Editorial. Consider if this might be clear:

OLD
  Write operations (e.g., edit-config)
  to these data nodes without proper protection can break or
  incorrectly connect DetNet flows.
  Since this is a configured Data
  Plane any changes that are not coordinated with all devices along the
  path the whole DetNet module is considered vulnerable and should have
  authorized access only.

NEW
Unauthorized write operations (e.g., edit-config) to any elements of this module can break or incorrectly connect DetNet flows. Since DetNet is a configured Data Plane, any changes that are not coordinated with all devices along the path will create a denial of service.

-- Is it possible quantify the security impact of these changes beyond a DoS?  Is the following accurate, or is coordinate required in the path required?

NEW
Additional, arbitrary write operations could also enable an attacker to modify a network topology to enable select traffic to avoid inspection or treatment by security controls, or route traffic in a way that it would be subject to inspect/modification by an adversary node.

** Section 10.  Per the read operations:

These are the subtrees and data
  node and their sensitivity/vulnerability:

  /detnet/app-flows: This controls the application details so it could
  be considered sensitive.

  /detnet/traffic-profile/member-app: This links traffic profiles to
  applications, service sub-layers and/or and forwarding sub-layers so
  this also could be considered more sensitive.

  /detnet/service/sub-layer/incoming/app-flow: This links applications
  to services.

  /detnet/service/sub-layer/outgoing/app-flow: This links applications
  to services.

-- Please amend the text to explain why these nodes are sensitive (i.e., why revealing this information is a problem).

-- Is there confidence that only these nodes are read sensitive?  Wouldn’t almost every part of the module reveal internal topology which would inform the targeting of an attacker?

[Ballot comment]
Hi Authors,

Thanks for this draft and for standardising another IETF YANG module.  I think that the detailed examples (and diagrams) will likely be particularly helpful.

I only have a couple of trivial comments, otherwise is all looked good to me.

Minor level comments:

(1) p 3, sec 4.  DetNet YANG Module

    In the MPLS cases once encapsulated, the IP 6-tuple
  parameters may not be required to be programmed again.  In the IP
  case, without encapsulation, various IP flow id parameters must be
  configured along the flow path.

Perhaps include a reference to where 6-tuple is defined.



Nit level comments:

(2) p 5, sec 4.3.  DetNet Forwarding Sub-layer YANG Attributes

  *  Since this model programs the data plane existing explicit route
      mechanisms can be reused.

Perhaps "... the data place, existing ..."

Regards,
Rob

[Ballot comment]
Thank you for this document -- usually I dread reading YANG documents, but this one was surprisingly clean, understandable, etc.

After reading John's comment ("When reviewing, do *not* attempt to follow the examples in Appendix B without referring to one of the renderings that shows you the SVGs...") I was getting ready to DISCUSS, as I believe that all RFCs should render completely in ASCII -- but in this case the SVG is so clean and useful that I'm actually OK with it -- this has somewhat shaken my world view :-))

[Ballot comment]
# Internet AD comments for draft-ietf-detnet-yang-19
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

### S8

* ipsec-spi is also defined in the same way in RFC 4302.  RFC 4301 says
  it's a 32-bit number, but doesn't seem to say anything about zero being
  reserved.

## Nits

### S4

* The section references for the sub-layers are all 3.x and look like they
  should 4.x

[Ballot comment]
When reviewing, do *not* attempt to follow the examples in Appendix B without referring to one of the renderings that shows you the SVGs (I use the HTML rendering, but HTMLized and PDF work too).

There was one substantive review during IETF Last Call, https://mailarchive.ietf.org/arch/msg/last-call/OVHml_-WJx100VnJBAIbNngmNbM/

Authors, please take a look and revise the document if needed, or follow up with the reviewer otherwise. Thanks!

(It also appears some other reviews are pending, but I won't hold up the document for those if they don't materialize in time.)

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

IANA has completed its review of draft-ietf-detnet-yang-18. 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-detnet
URI: urn:ietf:params:xml:ns:yang:ietf-detnet
Filename: [ TBD-at-Registration ]
Reference: [ RFC-to-be ]

As this requests a registration in an Expert Review or Specification Required (see RFC 8126) registry, we have performed the required Expert Review via a separate request. The registration has been approved, with the following comment by one of the experts:

"For the record, like many YANG models, it uses XML in a way that that is not a best practice - using namespace prefixes in element content - but any XML processor that is routinely used for YANG will probably be able to handle this since many YANG models do this."

Second, in the YANG Module Names registry on 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-detnet
File: [ TBD-at-Registration ]
Maintained by IANA? N
Namespace: urn:ietf:params:xml:ns:yang:ietf-detnet
Prefix: dnet
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 ns (IETF XML Registry) registration is approved, with a comment from the experts: For the record, like many YANG models, it uses XML in a way that that is not a best practice - using namespace prefixes in element content - but any XML processor that is routinely used for YANG will probably be able to handle this since many YANG models do this.

The following Last Call announcement was sent out (ends 2023-12-19):

From: The IESG
To: IETF-Announce
CC: detnet-chairs@ietf.org, detnet@ietf.org, draft-ietf-detnet-yang@ietf.org, janos.farkas@ericsson.com, jgs@juniper.net
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (Deterministic Networking (DetNet) YANG Model) to Proposed Standard


The IESG has received a request from the Deterministic Networking WG (detnet)
to consider the following document: - 'Deterministic Networking (DetNet) YANG
Model'
  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 2023-12-19. 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 contains the specification for the Deterministic
  Networking YANG Model for configuration and operational data of
  DetNet Flows.  The model allows for provisioning of end-to-end DetNet
  service on devices along the path without dependency on any signaling
  protocol.  It also specifies operational status for flows.

  The YANG module defined in this document conforms to the Network
  Management Datastore Architecture (NMDA).




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



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


The document contains these normative downward references.
See RFC 3967 for additional information:
    rfc8938: Deterministic Networking (DetNet) Data Plane Framework (Informational - Internet Engineering Task Force (IETF))
    rfc9016: Flow and Service Information Model for Deterministic Networking (DetNet) (Informational - Internet Engineering Task Force (IETF))

As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated 1 November 2019.

(1) What type of RFC is being requested (BCP, Proposed Standard, Internet Standard, Informational, Experimental, or Historic)? Why is this the proper type of RFC? Is this type of RFC indicated in the title page header?

  The intended status is Standards Track. This is the appropriate status because the document defines a YANG module. The type is indicated in the page header.


(2) The IESG approval announcement includes a Document Announcement Write-Up. Please provide such a Document Announcement Write-Up. Recent examples can be found in the "Action" announcements for approved documents. The approval announcement contains the following sections:

Technical Summary:

  This document specifies the Deterministic Networking YANG Model for configuration and operational data for DetNet Flows. The model allows for provisioning of end-to-end DetNet service on devices along the path without dependency on any signaling protocol. It also specifies operational status for flows. An operator or network controller programs the configuration of the devices.


Relevant content can frequently be found in the abstract and/or introduction of the document. If not, this may be an indication that there are deficiencies in the abstract or introduction.

Working Group Summary:

  The normal WG process has been followed and the documents reflect WG consensus with nothing special worth mentioning.


Was there anything in WG process that is worth noting? For example, was there controversy about particular points or were there decisions where the consensus was particularly rough?

  Nothing notable.


Document Quality:

  It is a good quality document. The Shepherd is satisfied with the review through WG Last Call and believes the document is ready for IETF Last Call.


Are there existing implementations of the protocol? Have a significant number of vendors indicated their plan to implement the specification? Are there any reviewers that merit special mention as having done a thorough review, e.g., one that resulted in important changes or a conclusion that the document had no substantive issues? If there was a MIB Doctor, YANG Doctor, Media Type or other expert review, what was its course (briefly)? In the case of a Media Type review, on what date was the request posted?

  While there is interest in this specification from multiple vendors, there are no publicly known implementations yet.
  The document is one of the key deliverables of the WG to make DetNet happen.
  YANG Doctor provided thorough early review with detailed comments, which all have been addressed.


Personnel:

Who is the Document Shepherd? Who is the Responsible Area Director?

  János Farkas is the Document Shepherd, John Scudder is the Responsible AD.


(3) Briefly describe the review of this document that was performed by the Document Shepherd. If this version of the document is not ready for publication, please explain why the document is being forwarded to the IESG.

  The Shepherd reviewed this document as part of WG Last Call as well as it progressed through the WG including the open and informal working meetings of the WG to progress the document.  All WG Last Call and early YANG Doctor comments have been addressed.


(4) Does the document Shepherd have any concerns about the depth or breadth of the reviews that have been performed?

  No.


(5) Do portions of the document need review from a particular or from broader perspective, e.g., security, operational complexity, AAA, DNS, DHCP, XML, or internationalization? If so, describe the review that took place.

  No.


(6) Describe any specific concerns or issues that the Document Shepherd has with this document that the Responsible Area Director and/or the IESG should be aware of? For example, perhaps he or she is uncomfortable with certain parts of the document, or has concerns whether there really is a need for it. In any event, if the WG has discussed those issues and has indicated that it still wishes to advance the document, detail those concerns here.

  No concerns.


(7) Has each author confirmed that any and all appropriate IPR disclosures required for full conformance with the provisions of BCP 78 and BCP 79 have already been filed. If not, explain why?

  Yes, see: https://mailarchive.ietf.org/arch/msg/detnet/v3fTZHSphBQKbpmLs5pkmCQwkbc/.


(8) Has an IPR disclosure been filed that references this document? If so, summarize any WG discussion and conclusion regarding the IPR disclosures.

  No IPR.


(9) How solid is the WG consensus behind this document? Does it represent the strong concurrence of a few individuals, with others being silent, or does the WG as a whole understand and agree with it?

  Very solid.  The document is mature and has been discussed sufficiently.


(10) Has anyone threatened an appeal or otherwise indicated extreme discontent? If so, please summarise 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.


(11) Identify any ID nits the Document Shepherd has found in this document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts Checklist). Boilerplate checks are not enough; this check needs to be thorough.

  No issues.


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

  A thorough early YANG Doctor review has been provided with detailed comments, which all have been addressed.


(13) Have all references within this document been identified as either normative or informative?

  Yes.


(14) Are there normative references to documents that are not ready for advancement or are otherwise in an unclear state? If such normative references exist, what is the plan for their completion?

  No.


(15) Are there downward normative references references (see RFC 3967)? If so, list these downward references to support the Area Director in the Last Call procedure.

  - RFC 9016 Flow and Service Information Model for Deterministic Networking (DetNet)
  - RFC 9055 Deterministic Networking (DetNet) Security Considerations
  They are required to properly understand and implement the document.
  (See also: https://mailarchive.ietf.org/arch/msg/detnet/y6wMHmwRKNpxyp8pAPb0R9Hj54Y/.)


(16) Will publication of this document change the status of any existing RFCs? Are those RFCs listed on the title page header, listed in the abstract, and discussed in the introduction? If the RFCs are not listed in the Abstract and Introduction, explain why, and point to the part of the document where the relationship of this document to the other RFCs is discussed. If this information is not in the document, explain why the WG considers it unnecessary.

  No.

(17) 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 protocol extensions that the document makes are associated with the appropriate reservations in IANA registries. Confirm that any referenced IANA registries have been clearly identified. Confirm that newly created IANA registries include a detailed specification of the initial contents for the registry, that allocations procedures for future registrations are defined, and a reasonable name for the new registry has been suggested (see RFC 8126).

  The IANA section is consistent and includes detailed specifications for the registry.


(18) List any new IANA registries that require Expert Review for future allocations. Provide any public guidance that the IESG would find useful in selecting the IANA Experts for these new registries.

  None.


(19) Describe reviews and automated checks performed by the Document Shepherd to validate sections of the document written in a formal language, such as XML code, BNF rules, MIB definitions, YANG modules, etc.

  The Shepherd checked ID nits and performed YANG validation, which resulted in no errors or warnings.


(20) If the document contains a YANG module, has the module been checked with any of the recommended validation tools (https://trac.ietf.org/trac/ops/wiki/yang-review-tools) for syntax and formatting validation? If there are any resulting errors or warnings, what is the justification for not fixing them at this time? Does the YANG module comply with the Network Management Datastore Architecture (NMDA) as specified in RFC8342?

  YANG validation resulted in no errors or warnings.

As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated 1 November 2019.

(1) What type of RFC is being requested (BCP, Proposed Standard, Internet Standard, Informational, Experimental, or Historic)? Why is this the proper type of RFC? Is this type of RFC indicated in the title page header?

  The intended status is Standards Track. This is the appropriate status because the document defines a YANG module. The type is indicated in the page header.


(2) The IESG approval announcement includes a Document Announcement Write-Up. Please provide such a Document Announcement Write-Up. Recent examples can be found in the "Action" announcements for approved documents. The approval announcement contains the following sections:

Technical Summary:

  This document specifies the Deterministic Networking YANG Model for configuration and operational data for DetNet Flows. The model allows for provisioning of end-to-end DetNet service on devices along the path without dependency on any signaling protocol. It also specifies operational status for flows. An operator or network controller programs the configuration of the devices.


Relevant content can frequently be found in the abstract and/or introduction of the document. If not, this may be an indication that there are deficiencies in the abstract or introduction.

Working Group Summary:

  The normal WG process has been followed and the documents reflect WG consensus with nothing special worth mentioning.


Was there anything in WG process that is worth noting? For example, was there controversy about particular points or were there decisions where the consensus was particularly rough?

  Nothing notable.


Document Quality:

  It is a good quality document. The Shepherd is satisfied with the review through WG Last Call and believes the document is ready for IETF Last Call.


Are there existing implementations of the protocol? Have a significant number of vendors indicated their plan to implement the specification? Are there any reviewers that merit special mention as having done a thorough review, e.g., one that resulted in important changes or a conclusion that the document had no substantive issues? If there was a MIB Doctor, YANG Doctor, Media Type or other expert review, what was its course (briefly)? In the case of a Media Type review, on what date was the request posted?

  While there is interest in this specification from multiple vendors, there are no publicly known implementations yet.
  The document is one of the key deliverables of the WG to make DetNet happen.
  YANG Doctor provided thorough early review with detailed comments, which all have been addressed.


Personnel:

Who is the Document Shepherd? Who is the Responsible Area Director?

  János Farkas is the Document Shepherd, John Scudder is the Responsible AD.


(3) Briefly describe the review of this document that was performed by the Document Shepherd. If this version of the document is not ready for publication, please explain why the document is being forwarded to the IESG.

  The Shepherd reviewed this document as part of WG Last Call as well as it progressed through the WG including the open and informal working meetings of the WG to progress the document.  All WG Last Call and early YANG Doctor comments have been addressed.


(4) Does the document Shepherd have any concerns about the depth or breadth of the reviews that have been performed?

  No.


(5) Do portions of the document need review from a particular or from broader perspective, e.g., security, operational complexity, AAA, DNS, DHCP, XML, or internationalization? If so, describe the review that took place.

  No.


(6) Describe any specific concerns or issues that the Document Shepherd has with this document that the Responsible Area Director and/or the IESG should be aware of? For example, perhaps he or she is uncomfortable with certain parts of the document, or has concerns whether there really is a need for it. In any event, if the WG has discussed those issues and has indicated that it still wishes to advance the document, detail those concerns here.

  No concerns.


(7) Has each author confirmed that any and all appropriate IPR disclosures required for full conformance with the provisions of BCP 78 and BCP 79 have already been filed. If not, explain why?

  Yes, see: https://mailarchive.ietf.org/arch/msg/detnet/v3fTZHSphBQKbpmLs5pkmCQwkbc/.


(8) Has an IPR disclosure been filed that references this document? If so, summarize any WG discussion and conclusion regarding the IPR disclosures.

  No IPR.


(9) How solid is the WG consensus behind this document? Does it represent the strong concurrence of a few individuals, with others being silent, or does the WG as a whole understand and agree with it?

  Very solid.  The document is mature and has been discussed sufficiently.


(10) Has anyone threatened an appeal or otherwise indicated extreme discontent? If so, please summarise 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.


(11) Identify any ID nits the Document Shepherd has found in this document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts Checklist). Boilerplate checks are not enough; this check needs to be thorough.

  No issues.


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

  A thorough early YANG Doctor review has been provided with detailed comments, which all have been addressed.


(13) Have all references within this document been identified as either normative or informative?

  Yes.


(14) Are there normative references to documents that are not ready for advancement or are otherwise in an unclear state? If such normative references exist, what is the plan for their completion?

  No.


(15) Are there downward normative references references (see RFC 3967)? If so, list these downward references to support the Area Director in the Last Call procedure.

  - RFC 9016 Flow and Service Information Model for Deterministic Networking (DetNet)
  - RFC 9055 Deterministic Networking (DetNet) Security Considerations
  They are required to properly understand and implement the document.
  (See also: https://mailarchive.ietf.org/arch/msg/detnet/y6wMHmwRKNpxyp8pAPb0R9Hj54Y/.)


(16) Will publication of this document change the status of any existing RFCs? Are those RFCs listed on the title page header, listed in the abstract, and discussed in the introduction? If the RFCs are not listed in the Abstract and Introduction, explain why, and point to the part of the document where the relationship of this document to the other RFCs is discussed. If this information is not in the document, explain why the WG considers it unnecessary.

  No.

(17) 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 protocol extensions that the document makes are associated with the appropriate reservations in IANA registries. Confirm that any referenced IANA registries have been clearly identified. Confirm that newly created IANA registries include a detailed specification of the initial contents for the registry, that allocations procedures for future registrations are defined, and a reasonable name for the new registry has been suggested (see RFC 8126).

  The IANA section is consistent and includes detailed specifications for the registry.


(18) List any new IANA registries that require Expert Review for future allocations. Provide any public guidance that the IESG would find useful in selecting the IANA Experts for these new registries.

  None.


(19) Describe reviews and automated checks performed by the Document Shepherd to validate sections of the document written in a formal language, such as XML code, BNF rules, MIB definitions, YANG modules, etc.

  The Shepherd checked ID nits and performed YANG validation, which resulted in no errors or warnings.


(20) If the document contains a YANG module, has the module been checked with any of the recommended validation tools (https://trac.ietf.org/trac/ops/wiki/yang-review-tools) for syntax and formatting validation? If there are any resulting errors or warnings, what is the justification for not fixing them at this time? Does the YANG module comply with the Network Management Datastore Architecture (NMDA) as specified in RFC8342?

  YANG validation resulted in no errors or warnings.

Request for posting confirmation emailed to previous authors: Don Fedyk , Mach Chen , Reshad Rahman , Xuesong Geng , Yeoncheol Ryoo , Zhenqiang Li , detnet-chairs@ietf.org

Request for posting confirmation emailed to previous authors: Don Fedyk , Mach Chen , Reshad Rahman , Yeoncheol Ryoo , detnet-chairs@ietf.org, Zhenqiang Li , Xuesong Geng