RIFT: Routing in Fat Trees
draft-ietf-rift-rift-21

[Ballot discuss]
# Gunter Van de Velde, RTG AD, comments for draft-ietf-rift-rift-21

Thanks to the authors for the epic amount of work put into this document.
Thanks to Loa Andersson, Jonathan Hardwick and Russ White for their valuable RTG DIR reviews
Thanks to Zheng Zhang for the shepherd writeup

Please find some some blocking DISCUSS items (easy to resolve) and a few non-blocking COMMENT points.

Please find https://www.ietf.org/blog/handling-iesg-ballot-positions/ documenting the handling of ballots.

#DISCUSS items
#=============
359   First, it introduces RIFT's packet format content in the form of a
360   normative Thrift model given in Appendix B.3 carried in according

[DISCUSS#1] Normative statements are normally not added in Appendixes. 
Normative content, procedure rules that must be followed to conform
to the standard, is typically found in the main body of the document.

[DISCUSS#2] What is the difference between Distance and Cost used in the document?
These are both in the terminology section, however the difference is unclear (to me).
Both are used within the document extensive. Readers understanding of the
difference is paramount.

[DISCUSS#3] Section 6.2 talks about MTU. I have seen often issues between
neighbors due to (accidental) MTU mismatches. In addition the section
assumes that MTU (transmit) == MRU (receive). Beyond this it is
not specified if this is the L2 MTU or L3 MTU? Often the MTU
on the wire depends upon the L2/L3 encap used. The specifics should be nailed
down on what is intended as the MTU used for RIFT schema.

[DISCUSS#4] Section 6.7 about ZTP. Often the terminology ZTP is associated with
securely adding/booting nodes into a network and guarding none have been
tampered with. ZTP in section 6.7 however seems to describe ZTP from
the perspective of RIFT to allow a node to figure out its level, its
neighbors and its RIFT centric configuration. Unless somewhere else specified
a more explicit RIFT ZTP goals, non-goals and objectives will be help. In section 6.9
some of this is touched upon, however i found the role (current and potential
future extensions) of section 6.7 ZTP somewhat unclear from this perspective.

[Ballot comment]
#GENERIC COMMENTS
#================
##The document is well written in both descriptive and normative style.
In general a wonderful achievement from the authors. i did wonder however
if certain sections can not be made less complicated and with less
wide scope to lower the threshold level for implementers to implement RIFT.

##The document is very long and is an intense complex read. I can
not claim i understand everything in super detail as that would take a
lot more time then available to digest/review this document.

##The security section 9 is a nice security overview of RIFT with loads of details

##The abstract appears to present a rationale for employing Clos or
fat pipe topologies in IP fabrics. However, I would argue that the primary intent
of RIFT is not to justify the use of these specific topologies but is aimed
to be a routing protocol specifically designed for these architectures.

The abstract should provide a glimpse into what RIFT is about. What about
this conceptual rewrite proposal:

    "The document details the Routing in Fat Trees (RIFT) protocol, specifically
    designed for use in Clos and fat-tree network topologies. It aims to reduce
    the complexity and state requirements of the control plane in these networks.
    RIFT addresses both the configuration and operational aspects, enhancing
    efficiency through specialized mechanisms."

##May i suggest add the following introduction summary overview into the introduction
section an overview of the key promised features from RIFT.

Key features of RIFT include:

Topology Awareness: RIFT is tailored for networks with a clear "top" and "bottom",
which is typical of Clos or fat-tree structures. This orientation allows for
optimized data flow management.

Dual Functionality: The protocol functions as a link-state protocol when
routing "north" and as a path-vector protocol when routing "south". This dual
approach helps in efficiently managing the routing information.

Flooding Mechanisms: RIFT employs selective flooding techniques to limit
the spread of routing information to necessary nodes only, thereby
reducing overhead.

Zero Touch Provisioning (ZTP): RIFT supports ZTP, which allows devices
to be configured automatically with minimal manual intervention, leveraging
the structured nature of fat-tree topologies.

Topology Exchange: Through Topology Information Elements (TIEs), RIFT handles
the dissemination of topology and routing information, facilitating both northbound
and southbound routing directions.

Failure Management: The protocol includes mechanisms for handling link
and node failures effectively, using concepts like automatic disaggregation
to maintain network stability and route availability.

Efficient Convergence: RIFT is designed to achieve fast convergence
across large and complex topologies, essential for maintaining high availability
and performance in data center environments.

##YANG data model vs KV store
The document includes a KV datastore, but makes no statement or indication about
YANG models/keys/lists. Seems as a missed opportunity

#DETAILED COMMENTS
#=================

classified as [minor] and [major]

359   First, it introduces RIFT's packet format content in the form of a
360   normative Thrift model given in Appendix B.3 carried in according

[minor] Thrift model: Thrift is a software framework for scalable cross-language
services development. Maybe the pointer to the reference should be used at
first occurrence. There is a reference, but its not added to the first
terminology occurrence but at a later moment.

406   Section 7 contains a set of comprehensive examples that show how RIFT
407   contains the impact of failures to only the required set of nodes.
408   It should also help cement some of RIFT's core concepts in the
409   reader's mind.

[minor] Should section 7 be better located in an informative appendix
to reduce the normative part of the RIFT procedures

411   Last, but not least, RIFT has other optional capabilities.  One
412   example is the key-value data-store, which enables RIFT to advertise
413   data post-convergence in order to bootstrap higher levels of
414   functionality (e.g. operational telemetry).  Those are covered in
415   Section 6.8.

[minor] KV store seems close aligned with how the yang model will look like.
However, the word yang only appears once for a different purpose. intentional?

452   Clos/Fat Tree:
453       This document uses the terms Clos and Fat Tree interchangeably
454       where it always refers to a folded spine-and-leaf topology with
455       possibly multiple Points of Delivery (PoDs) and one or multiple
456       Top of Fabric (ToF) planes.  Several modifications such as leaf-
457       2-leaf shortcuts and multiple level shortcuts are possible and
458       described further in the document.

[minor] It would be useful to at least introduce once what is exactly a fat
tree topology. This seems as a fine location for that purpose.
"A fat tree topology is a structured network design that is commonly
used in large-scale and high-performance computing environments, including
data centers. This topology is a variation of the tree topology, characterized by
increased bandwidth closer to the root of the tree where traffic
concentration is higher."

460   Cost:
461       The sum of metrics between two nodes.
...
479   Distance:
480       The sum of costs (bound by infinite distance) between two nodes.

[major] I have no idea what the difference between Cost and Distance is based
upon this description. Can this be explained better?

505   Leaf-to-Leaf Shortcuts (L2L):
506       East-West links at leaf level will need to be differentiated from
507       East-West links at other levels.

[minor] risk for Terminology confusion. A "shortcut" typically, especially used
with MPLS, refers to a technique used to optimize the path that data
takes through a network, potentially bypassing certain nodes or segments
to improve performance, reduce latency, or manage bandwidth more effectively.
The shortcut here seems something else? is shortcut the best term to
use for this?

847   the overhead of building an update per adjacency.  For the moment
848   describing the East-West direction is left out.

[minor] "left out" of the RIFT specification or out of the current section?

860   reachability information from multiple directions.  Its computation
861   principles (south forwarding direction is always preferred) leads to
862   valley-free [VFR] forwarding behavior.  And since valley free routing
863   is loop-free, it can use all feasible paths.  This is another highly

[minor] i was not familiar with the term Valley-Free routing.
I did some research and found that in valley-free routing, a route is considered
valid if it only traverses paths that go up the hierarchy (from a lower-tier level
to a higher-tier level) or horizontally (between levels of the same tier), and then
potentially down the hierarchy (from a higher-tier level to a lower-tier level).
What it avoids is the "valley" - a path that goes up and then down through level
tiers without proper hierarchical or commercial rationale, such as
going from a lower-tier level up to a higher-tier and then back down
to another lower-tier level.
Maybe few summary words could be provided beyond the reference provided.

1307 5.3.  Fallen Leaf Problem

[minor] The text illustrates the complexity of managing a fabric network
under the RIFT protocol, emphasizing the need for dynamic response
strategies to maintain connectivity and ensure robust network performance
in various failure scenarios.

Can an easy to digest summary of the dynamic response by RIFT to
the fallen leaf problem be added to the section to guide the reader
into section 5.4 and 5.5?

1590   RIFT supports any combination of IPv4 and IPv6 addressing on the
1591   fabric with the additional capability for forwarding paths that are
1592   capable of forwarding IPv4 packets in presence of IPv6 addressing
1593   only.

[major#1] does RIFT care about address scopes used? i.e. Link-locals or unnumbered
interfaces using interface id's, etc
[major#2] Does RIFT allow one side to be IPv4-only and the other side IPv6-only?
There is a table later explaining some aspects, but that may not to fully
conform to the perceived allowed addressing combinations. 

1600   schema Appendix B.2 is used unless configured otherwise.  LIEs MUST
1601   be sent with an IPv4 Time to Live (TTL) or an IPv6 Hop Limit (HL) of
1602   either 1 or 255 to prevent RIFT information reaching beyond a single
1603   L3 next-hop in the topology.  LIEs SHOULD be sent with network

[major] what hapens if LIE is sent with another TTL? silently ignored or error message
returned or something else??

1624   A simplified version MAY be implemented on platforms with limited or
1625   no multicast support (e.g.  IoT devices) by sending and receiving LIE
1626   frames on IPv4 subnet broadcast addresses or IPv6 all routers
1627   multicast address.  However, this technique is less optimal and
1628   presents a wider attack surface from a security perspective.

[minor] i assumed that RIFT find applicability in fat tree architectures. These architecture
tend not to be IoT devices. This make me wonder if this paragraph is needed?

1690       Table 1: Control Plane Behavior for Neighbor AF Combinations

[minor] Why is the IPv4,IPv6 -> IPv4 not included in this table? the IPv4,IPv6 -> IPv6 is
included however.

1757   1.  the neighboring node is running the same major schema version as
1758       indicated in the _major_version_ element in _PacketHeader_ *and*

[major] the difference between a RIFT version number and the schema version is unclear.
I may missed reading it when going through the document. What about an text blob about Thrift
schema version in section 2 to provide context about 'what-is-this-schema-version' used
with RIFT KV datastore and how it differs from RIFTversion number.

1767   4.  (the advertised MTU values in the _LiePacket_ element match on
1768       both sides while a missing MTU in the _LiePacket_ element is
1769       interpreted as _default_mtu_size_) *and*

[major] i have been exposed to loads of troubleshooting and HW troubles
when MTU is mentioned with protocols. Also the MRU (Maximum Receive Unit) is
a property different as the MTU. Is it assumed that L2 encaps play a role in the MTU?

Accordingly, MTU can be seen in Different Contexts. Which ones is implied for RIFT?
Ethernet: The standard MTU for Ethernet is typically 1500 bytes.
Internet (IPv4 and IPv6): For internet traffic, the MTU considerations
become more complex due to the need to traverse multiple networks of
potentially varying capabilities.

4135 6.7.  Optional Zero Touch Provisioning (ZTP)

4137   Each RIFT node can operate in zero touch provisioning (ZTP) mode,
4138   i.e. it has no configuration (unless it is a ToF or it is explicitly
4139   configured to operate in the overall topology as leaf and/or support
4140   leaf-2-leaf procedures) and it will fully configure itself after
4141   being attached to the topology.  Configured nodes and nodes operating
4142   in ZTP can be mixed and will form a valid topology if achievable.

[major] in DC environment security is important. In some DCs i visited each device
plugged into the network is authenticated before allowed being connected.

Maybe the ZTP used for device security is a different ZTP to be used for
RIFT and they can be considered as ships-in-the-night solutions?.

5350   RIFT MAGIC:
5351       16 bits.  Constant value of 0xA1F7 that allows easy classification
5352       of RIFT packets independent of the UDP port used.

[minor] Out of interest, why is this particular number chosen? What happens if
a different value is encoded? will the RIFT MAGIC number have secret RIFT Protocol Versioning embedded?

5501   There in no mechanism to convert a security envelope for the same Key
5502   ID from one algorithm to another once the envelope is operational.

[minor] "There in" looks as a typo. Not sure if there are few words misisng.

[Ballot comment]
# Orie Steele, ART AD, comments for draft-ietf-rift-rift-21
CC @OR13

This review is in the ["IETF Comments" Markdown format][ICMF].
You can use the [`ietf-comments` tool][ICT] to automatically convert this review into
individual GitHub issues, or using this [online validator](https://mnot.github.io/ietf-comments/).

Line numbers are generated with this:
https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-rift-rift-21.txt&submitcheck=True

## Comments

```
1458 Figure 13: Using rings to bring all planes and at the ToF bind them
```
love this.

## Nits

### List Formatting

```
1774   6.  [

1776           i) the node is at _leaf_level_ value and has no _ThreeWay_
1777           adjacencies already to nodes at Highest Adjacency _ThreeWay_
1778           (HAT as defined later in Section 6.7.1) with level different
1779           than the adjacent node *or*

1781           ii) the node is not at _leaf_level_ value and the neighboring
1782           node is at _leaf_level_ value *or*

1784           iii) both nodes are at _leaf_level_ values *and* both indicate
1785           support for Section 6.8.9 *or*
1786           iv) neither node is at _leaf_level_ value and the neighboring
1787           node is at most one level difference away

1789       ].
```

The use of brackets and absence of sub bullets, is slightly confusing.

### Text based emphasis

```
1723   The protocol does *not* support selective disabling of address
1724   families after adjacency formation, disabling IPv4 forwarding
```

I'm *not* a huge fan or text based emphasis, it does not translate well into HTML.

### Spelling

```
715   Zero Touch Provisioning (ZTP):
716       Optional RIFT mechanism which allows the automatic derivation of
717       node levels based on minimum configuration.  Such a mininum
718       configuration consists solely of ToFs being configured as such.
```

mininum -> minimum

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?
  The WG consensus is solid.

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 recommends) or elsewhere
(where)?
  Yes. At least two implementations existed.

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. The contents of this document have no closely interact with technologies
in other IETF WG or external organizations.

6. Describe how the document meets any required formal expert review criteria,
such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.
  No formal review required.

7. If the document contains a YANG module, has the final version of the module
been checked with any of the recommended validation 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 RFC 8342?
  No.

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.
  Thrift compilers have successfully generated automatic code from the
Information Elements Schema defined in Appendix B, which are used in two
interoperable implementations.

Document Shepherd Checks
9. Based on the shepherd's review of the document, is it their opinion that this
document is needed, clearly written, complete, correctly designed, and ready
to be handed off to the responsible Area Director?
  This document is ready for publication.  The document shepherd has done a
complete and general review of the Document. All issues that were raised in the
working group have been addressed. A new version (-17) with nits modification
is going to be published. This document is ready to be submitted to IESG.

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

11. What type of RFC publication is being requested on the IETF stream (Best
Current Practice, Proposed Standard, Internet Standard,
Informational, Experimental or Historic)? Why is this the proper type
of RFC? Do all Datatracker state attributes correctly reflect this intent?
  The intended status is Proposed Standards. It is indicated in the header.
It matches with the content of the Document which defines protocol procedures.
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? 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. All Authors and Contributors have made a statement regarding their
knowledge of IPR which would relate to this Document. Six IPR disclosures
have been made against this Document. The WG did not raise any issue with
the existence of these IPR.

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 number of authors exceeds five. The sixth co-author Jordan Head is the
main editor of version 16. He did great job to improve the draft.

14. Document any remaining I-D nits in this document. Simply running the idnits
tool is not enough; please review the "Content Guidelines" on
authors.ietf.org. (Also note that the current idnits tool generates
some incorrect warnings; a rewrite is underway.)
  Some idnits noise exist, but only editorial changes needed.

15. Should any informative references be normative or vice-versa? See the IESG
Statement on Normative and Informative References.
  No.

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

17. Are there any normative downward references (see RFC 3967 and BCP
97) that are not already listed in the DOWNREF registry? 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.

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).
  There was a long thread with the AD about registry naming/structure.
Aligned with his suggestions, the document lists IANA registries to be created,
with reasonable names, detailed specification of initial contents and procedures
for future allocations (expert review).

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.
  Tony Przygienda, Bruno Rijsman and Pascal Thubert are suggested as the
IANA Experts for the new registries.

22. RIFT is uniquely justified to have more than 5 authors given its wide
scope and long time in development of specification. The authors listed all
contributed significant ideas or parts of the spec or participated heavily
in formatting/editing of the draft over long periods of times. I recommend
to add each of the authors for the reasons given below:
Jordan did huge amount of lifting as editor incl. svg etc.
Pascal contributed tons, whole theoretical framework/language of fabric,
mobility, negative disaggregation fib especially, reworked whole flood
reduction.
Bruno wrote open source and was on all early calls, found FSM problems.
Dmitry was on all early calls, contributed lots practical considerations
from operation's side.
'Alankar (which will be added again) the same, on all early things,
contributed lots original ideas.

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

IANA has completed its review of draft-ietf-rift-rift-20. If any part of this review is inaccurate, please let us know.

IANA has a question about the first and fourth actions requested in the IANA Considerations section of this document.

First, in the Service Name and Transport Protocol Port Number Registry located at:

https://www.iana.org/assignments/service-names-port-numbers/

the temporary registrations for:

Service Name: rift-lies
Port Number: 914
Transport Protocol: udp
Description: Routing in Fat Trees Link Information Elements
Assignee: IESG
Contact: IETF Chair
Reference: [ RFC-to-be ]

Service Name: rift-ties
Port Number: 915
Transport Protocol: udp
Description: Routing in Fat Trees Topology Information Elements
Assignee: IESG
Contact: IETF Chair
Reference: [ RFC-to-be ]

will be made permanent, their assignees and contacts updated, and their references changed to [ RFC-to-be ].

IANA Comment -> Would the authors be able to add the the templates from RFC 6335, Section 8.1 to Section 10.1 of this I-D?

Second, in the IPv4 Multicast Address Space registry group located at:

https://www.iana.org/assignments/multicast-addresses/

the temporary registration for:

Address: 224.0.0.121
Description: ALL_V4_RIFT_ROUTERS

will be made permanent and its reference changed to [ RFC-to-be ].

Third, in the IPv6 Multicast Address Space Registry group located at:

https://www.iana.org/assignments/ipv6-multicast-addresses/

the temporary registration for:

Address: FF02::A1F7
Description: ALL_V6_RIFT_ROUTERS

will be made permanent and its reference changed to [ RFC-to-be ].

Fourth, while the new top-level Routing in Fat Trees registry makes sense to IANA, the instructions in section 10.2 of the IANA Considerations Section appear to be contradictory. Section 10.2 says that "Allocation of new values is always performed via `Expert Review` action." However, nearly every registry in the subsequent section provides conflicting registration procedure instructions (see RFC8126). Which are the correct instructions for these registries?

In addition, it would be helpful to have explicit titles for the registries in each subsection of Section 10.2.

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 2024-03-05):

From: The IESG
To: IETF-Announce
CC: Zheng Zhang , aretana.ietf@gmail.com, draft-ietf-rift-rift@ietf.org, james.n.guichard@futurewei.com, rift-chairs@ietf.org, rift@ietf.org, zhang.zheng@zte.com.cn
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (RIFT: Routing in Fat Trees) to Proposed Standard


The IESG has received a request from the Routing In Fat Trees WG (rift) to
consider the following document: - 'RIFT: Routing in Fat Trees'
  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 2024-03-05. Exceptionally, comments may
be sent to iesg@ietf.org instead. In either case, please retain the beginning
of the Subject line to allow automated sorting.

Abstract


  This document defines a specialized, dynamic routing protocol for
  Clos and fat tree network topologies optimized towards minimization
  of control plane state as well as minimization of configuration and
  operational complexity.




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


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

  https://datatracker.ietf.org/ipr/2944/
  https://datatracker.ietf.org/ipr/3168/
  https://datatracker.ietf.org/ipr/3343/
  https://datatracker.ietf.org/ipr/3091/
  https://datatracker.ietf.org/ipr/3226/
  https://datatracker.ietf.org/ipr/3167/

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?
  The WG consensus is solid.

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 recommends) or elsewhere
(where)?
  Yes. At least two implementations existed.

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. The contents of this document have no closely interact with technologies
in other IETF WG or external organizations.

6. Describe how the document meets any required formal expert review criteria,
such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.
  No formal review required.

7. If the document contains a YANG module, has the final version of the module
been checked with any of the recommended validation 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 RFC 8342?
  No.

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.
  Thrift compilers have successfully generated automatic code from the
Information Elements Schema defined in Appendix B, which are used in two
interoperable implementations.

Document Shepherd Checks
9. Based on the shepherd's review of the document, is it their opinion that this
document is needed, clearly written, complete, correctly designed, and ready
to be handed off to the responsible Area Director?
  This document is ready for publication.  The document shepherd has done a
complete and general review of the Document. All issues that were raised in the
working group have been addressed. A new version (-17) with nits modification
is going to be published. This document is ready to be submitted to IESG.

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

11. What type of RFC publication is being requested on the IETF stream (Best
Current Practice, Proposed Standard, Internet Standard,
Informational, Experimental or Historic)? Why is this the proper type
of RFC? Do all Datatracker state attributes correctly reflect this intent?
  The intended status is Proposed Standards. It is indicated in the header.
It matches with the content of the Document which defines protocol procedures.
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? 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. All Authors and Contributors have made a statement regarding their
knowledge of IPR which would relate to this Document. Six IPR disclosures
have been made against this Document. The WG did not raise any issue with
the existence of these IPR.

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 number of authors exceeds five. The sixth co-author Jordan Head is the
main editor of version 16. He did great job to improve the draft.

14. Document any remaining I-D nits in this document. Simply running the idnits
tool is not enough; please review the "Content Guidelines" on
authors.ietf.org. (Also note that the current idnits tool generates
some incorrect warnings; a rewrite is underway.)
  Some idnits noise exist, but only editorial changes needed.

15. Should any informative references be normative or vice-versa? See the IESG
Statement on Normative and Informative References.
  No.

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

17. Are there any normative downward references (see RFC 3967 and BCP
97) that are not already listed in the DOWNREF registry? 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.

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).
  There was a long thread with the AD about registry naming/structure.
Aligned with his suggestions, the document lists IANA registries to be created,
with reasonable names, detailed specification of initial contents and procedures
for future allocations (expert review).

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.
  Tony Przygienda, Bruno Rijsman and Pascal Thubert are suggested as the
IANA Experts for the new registries.

Closed request for Early review by INTDIR with state 'Withdrawn': For now, as this document is at -12 and had "not ready/has issues" reviews from other directorates and has not been update since 5/25/2020, assume this document is dead for now.

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 Proposed Standards. It is indicated in the header.
  It matches with the content of the Document which defines protocol procedures.

(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 defines a specialized, dynamic routing protocol for Clos and fat-tree network topologies optimized towards minimization of configuration and operational complexity.

Working Group Summary:

    The RIFT WG supports the publication of this Document as a Proposed Standard RFC.

Document Quality:

    Several implementations of this technology exist.
    Many reviewers provide comments and suggestions.
    This document is clear and well-written.

Personnel:

    Zheng Zhang is the Document Shepherd.
    Alvaro Retana is the Responsible Area Director.

(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.

  This document is ready for publication.  The document shepherd has done a complete and general review of the Document.
  All issues that were raised in the working group have been addressed.
  A new version (-12) with nits modification is going to be published.
  This document is ready to be submitted to IESG.

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

  No concerns.

(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 such reviews needed.

(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 such concerns, all the outstanding issues have been resolved.

(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?

  All Authors and Contributors have made a statement regarding their knowledge of IPR which would relate to this Document.

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

  Six IPR disclosures have been made against this Document.
  The WG did not raise any issue with the existence of these 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?

  The WG consensus is solid.

(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 errors were found on the ID nits check, only idnits noise.

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

  No formal review required.

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

  Yes. With one update in version 12 of this document.

(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.

  No.

(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).

  There was a long thread with the AD about registry naming/structure. Aligned with his suggestions, the document lists IANA registries to be created, with reasonable names, detailed specification of initial contents and procedures for future allocations (expert review).

(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.

  Tony Przygienda, Bruno Rijsman and Pascal Thubert are suggested as the IANA Experts for the new registries.

(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.

  Thrift compilers have successfully generated automatic code from the Information Elements Schema defined in Appendix B, which are used in two interoperable implementations.

(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?

  No.

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 Proposed Standards. It is indicated in the header.
  It matches with the content of the Document which defines protocol procedures.

(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 defines a specialized, dynamic routing protocol for Clos and fat-tree network topologies optimized towards minimization of configuration and operational complexity.

Working Group Summary:

    The RIFT WG supports the publication of this Document as a Proposed Standard RFC.

Document Quality:

    Several implementations of this technology exist.
    Many reviewers provide comments and suggestions.
    This document is clear and well-written.

Personnel:

    Zheng Zhang is the Document Shepherd.
    Alvaro Retana is the Responsible Area Director.

(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.

  This document is ready for publication.  The document shepherd has done a complete and general review of the Document.
  All issues that were raised in the working group have been addressed.
  A new version (-12) with nits modification is going to be published.
  This document is ready to be submitted to IESG.

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

  No concerns.

(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 such reviews needed.

(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 such concerns, all the outstanding issues have been resolved.

(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?

  All Authors and Contributors have made a statement regarding their knowledge of IPR which would relate to this Document.

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

  Six IPR disclosures have been made against this Document.
  The WG did not raise any issue with the existence of these 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?

  The WG consensus is solid.

(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 errors were found on the ID nits check, only idnits noise.

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

  No formal review required.

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

  Yes. With one update in version 12 of this document.

(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.

  No.

(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).

  There was a long thread with the AD about registry naming/structure. Aligned with his suggestions, the document lists IANA registries to be created, with reasonable names, detailed specification of initial contents and procedures for future allocations (expert review).

(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.

  Tony Przygienda, Bruno Rijsman and Pascal Thubert are suggested as the IANA Experts for the new registries.

(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.

  Thrift compilers have successfully generated automatic code from the Information Elements Schema defined in Appendix B, which are used in two interoperable implementations.

(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?

  No.

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 Proposed Standards. It is indicated in the header.
  It matches with the content of the Document which defines protocol procedures.

(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 defines a specialized, dynamic routing protocol for Clos and fat-tree network topologies optimized towards minimization of configuration and operational complexity.

Working Group Summary:

    The RIFT WG supports the publication of this Document as a Proposed Standard RFC.

Document Quality:

    Several implementations of this technology exist.
    Many reviewers provide comments and suggestions.
    This document is clear and well-written.

Personnel:

    Zheng Zhang is the Document Shepherd.
    Alvaro Retana is the Responsible Area Director.

(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.

  This document is ready for publication.  The document shepherd has done a complete and general review of the Document.
  All issues that were raised in the working group have been addressed.
  A new version (-12) with nits modification is going to be published.
  This document is ready to be submitted to IESG.

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

  No concerns.

(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 such reviews needed.

(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 such concerns, all the outstanding issues have been resolved.

(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?

  All Authors and Contributors have made a statement regarding their knowledge of IPR which would relate to this Document.

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

  Six IPR disclosures have been made against this Document.
  The WG did not raise any issue with the existence of these 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?

  The WG consensus is solid.

(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 errors were found on the ID nits check, only idnits noise.

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

  No formal review required.

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

  Yes. With one update in version 12 of this document.

(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.

  No.

(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 document requests IANA actions.

(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.

  No.

(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.

  Not applicable.

(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?

  No.

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 Proposed Standards. It is indicated in the header.
  It matches with the content of the Document which defines protocol procedures.

(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 defines a specialized, dynamic routing protocol for Clos and fat-tree network topologies optimized towards minimization of configuration and operational complexity.

Working Group Summary:

    The RIFT WG supports the publication of this Document as a Proposed Standard RFC.

Document Quality:

    Several implementations of this technology exist.
    Many reviewers provide comments and suggestions.
    This document is clear and well-written.

Personnel:

    Zheng Zhang is the Document Shepherd.
    Alvaro Retana is the Responsible Area Director.

(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.

  This document is ready for publication.  The document shepherd has done a complete and general review of the Document.
  All issues that were raised in the working group have been addressed.
  A new version (-12) with nits modification is going to be published.
  This document is ready to be submitted to IESG.

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

  No concerns.

(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 such reviews needed.

(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 such concerns, all the outstanding issues have been resolved.

(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?

  All Authors and Contributors have made a statement regarding their knowledge of IPR which would relate to this Document.

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

  Six IPR disclosures have been made against this Document.
  The WG did not raise any issue with the existence of these 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?

  The WG consensus is solid.

(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 errors were found on the ID nits check, only idnits noise.

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

  No formal review required.

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

  Yes. With one update in version 12 of this document.

(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.

  No.

(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 document requests IANA actions.

(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.

  N/A.

(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.

  Not applicable.

(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?

  No.