T.140 Real-Time Text Conversation over WebRTC Data Channels
draft-ietf-mmusic-t140-usage-data-channel-14

[Ballot comment]
Thanks for the changes. I believe this substantially addresses my DISCUSS.

However, we've created a couple of nits:
- In Section 5.3, the MAY was added to the first paragraph instead of the second. I don't object to having one in the first paragraph, but don't feel it to be necessary.
- In 5.4, "channels.As" needs a space in there.


Old comment (which has been addressed):
The Tsvarea review cites a few other places where the 2119 language is a little loose, e.g. MUSTs with vague and unenforceable criteria.

[Ballot comment]
Thanks for the changes. I believe this substantially addresses my DISCUSS.

However, we've created a couple of nits:
- In Section 5.3, the MAY was added to the first paragraph instead of the second. I don't object to having one in the first paragraph, but don't feel it to be necessary.
- In 5.4, "channels.As" needs a space in there.


Old comment:
The Tsvarea review cites a few other places where the 2119 language is a little loose, e.g. MUSTs with vague and unenforceable criteria.

[Ballot comment]
I eagerly await further discussion of the TSV(-art/-AD) comments but
have nothing to contribute to such discussion.

It's kind of interesting that we negotiate the human language to be used
for the ... human-entered text.  Are we expecting the user-agents to
enforce the result of that negotiation, or just send whatever the users
type, even if it is in some other language?

Section 4.1

  The offerer and answerer MUST NOT include the max-retr or the max-
  time attribute parameters in the 'dcmap' attribute.  If any of the
  attribute parameters is received in an offer, the answerer MUST
  reject the offer.  If any of the attribute parameters is received in

s/any of the/either of those/? (twice)

Section 4.2.3.3

  If the answerer has not marked the direction of a T.140 data channel
  in accordance with the procedures above, it is RECOMMENDED that the
  offerer does not process that as an error situation, but rather
  assume that the answerer might both send and receive T.140 data on
  the data channel.

My SDP O/A is a bit rusty, but isn't that a divergence from the default
behavior of "treat it as an error"?  Perhaps we could say something
about why diverging from the default is deemed best.

Section 5.2

  Each T140block is sent on the SCTP stream [RFC4960] used to realize
  the T.140 data channel using standard T.140 transmission procedures
  [T140].  [...]

I'm not really sure what is meant by "standard T.140 transmission
procedures" -- is that supposed to cover the process by which the webrtc
stack receives the T.140 input or something done within webrtc?

  Data sending and reporting procedures conform to [T140].

I don't see any instance of the string "report" in
file:///home/bkaduk/Downloads/T-REC-T.140-199802-I!!PDF-E.pdf; am I
missing something?

Section 5.4

  might have been lost.  Different mechanisms used by sending and
  receiving endpoints to detect or suspect text loss are outside the
  scope of this specification.

I think I can accept that, but do we have reason to believe that any
such mechanisms are possible?

Section 6

  o  During a normal text flow, T140blocks received from one network
      are forwarded towards the other network.  Keep-alive traffic is
      implicit on the T.140 data channel.  A gateway might have to

I'm not sure what reference I should look at to understand what is meant
by "keep-alive traffic is implicit".

Section 7

I confess I don't really understand what part of RFC 8373 was media-type
specific and needed updating for use by this document.
I guess I could see a need for some new specification regarding the
attributes' usage, since we need something to point to for translating
them from media-level attributes to data-channel-level attributes, but
that doesn't seem to be what this is claiming to do.
draft-ietf-mmusic-data-channel-sdpneg seems to already cover the
general behavior that when data channels are used, they get
data-channel-level attributes for things that would be media attributes
of the corresponding subprotocol as a media type.  Maybe I'm more rusty
on SDP O/A than I thought...

Section 8

  The generic security considerations for WebRTC data channels are
  defined in [I-D.ietf-rtcweb-data-channel].  As data channels are

Perhaps it is worth pre-dereferencing the reference chain to
rtcweb-security and rtcweb-security-arch directly?

It also seems appropriate to reiterate the note from earlier in the
document that "no mechanism to provide end-to-end encryption of T.140
data is defined at the time of this writing" and the consequences
thereof when the channel itself is not end-to-end.

Section 11.1

We should maybe sprinkle a couple more RFC 3264 refs; the current one
doesn't seem to be in a normative manner (though I don't dispute the
status of 3264 as a normative reference!).

[Ballot comment]
** I support Martin Duke’s DISCUSS position.

** Section 5.4 
Initially:
“As a T.140 data channel does not provide a mechanism for the receiver to identify retransmitted  T140blocks after channel reestablishment, the sending endpoint MUST NOT retransmit T140blocks unless it has strong indications  that a T140block has been lost during the data channel failure.”

Later:
“Different mechanisms used by sending and receiving endpoints to detect or suspect text loss are outside the scope of this specification.”

How is this normative MUST NOT supposed to be evaluated if the the explanation of “strong indications” is not explained in this document and no reference is provided?

[Ballot discuss]
Section 4.1:

  The offerer and answerer MUST NOT include the max-retr or the max-
  time attribute parameters in the 'dcmap' attribute.

This is just an example of a issue that is exists in basically all of the RFC 2119 terminolgy using sentences in this section. The formulation is that the offerer or answerer must do something with attributes or parameters of the dcmap attribute. However, it is not stated to be specific to the dcmap attribute that specifically specify something for a T.140 SCTP stream. I think that scope restriction needs to be made more explicit for these RFC 2119 statements. Else they would have applicability as soon as one support this specification.

[Ballot comment]
Thanks for this document.  I have just one comment about BCP 14 key words that I don’t think has come up elsewhere:

— Section 5.3 —

  It is RECOMMENDED to use the
  default transmission interval of 300 milliseconds [RFC4103], for
  T.140 data channels.  Implementers MAY also use lower values, for
  specific applications requiring low latency, taking the increased
  overhead in consideration.

Given the “RECOMMENDED” in the first sentence, I don’t think the second sentence is really a BCP 10 “MAY”, but should be “may” (or “might”).  Actually, I think I would also remove the first comma, as, “Implementers might use lower values for specific applications requiring low latency, taking the increased overhead in consideration.”

[Ballot discuss]
I am confused as to the expected/allowed behavior regarding the cps attribute parameter.

In RFC 4103 Section 6 it says receivers MUST be able to handle temporary bursts over the cps rate but senders MUST stay below the rate.

In section 5.3 it says senders “can” (probably need a 2119 word here) buffer blocks to stay below cps. There is a 500ms limit so this has its limitations. Shouldn’t the buffer time be unbounded if characters are coming in at a rate above cps?

Meanwhile in section 4.2.1 it suggests that receivers use sendOnly or inactive (I presume these are the right direction values) to effectively flow control the incoming data. 4566bis seems to only envision this at the start of a channel. What is the impact of pending data if the directionality of the channel changes? How does this interact with the maximum buffer time?

I suggest 4.2.1 be clearer on what actions a cps sender and receiver MAY/SHOULD/MUST take, and make sure there aren’t contradictory requirements.

[Ballot comment]
Section 4.2.3.3:

Why might an implementer choose to deviate from the RECOMMENDED?

Section 5.5:

“This would allow the receiver to present real-time text from different sources separated.”

Did you mean “separately”?

“The procedures of such mechanism is outside the scope of this document.”

s/is/are/

Sections 9.2, 9.3, 9.4:

Please give the name of the registry being updated.

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

The IANA Functions Operator has completed its review of draft-ietf-mmusic-t140-usage-data-channel-11. If any part of this review is inaccurate, please let us know.

The IANA Functions Operator understands that, upon approval of this document, there are four actions which we must complete.

First, in the WebSocket Subprotocol Name Registry on the WebSocket Protocol Registries registry page located at:

https://www.iana.org/assignments/websocket/

Subprotocol identifier: t140
Subprotocol common name: ITU-T T.140
Subprotocol definition: [ RFC-to-be ]
Reference: [ RFC-to-be ]
Change controller:

Second, in the att-field registry on the Session Description Protocol (SDP) Parameters registry page located at:

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

the existing registration for the attribute fmtp is to be modified in accordance with [draft-ietf-mmusic-rfc4566bis] as follows:

Usage level: dcsa(t140)
Attribute name: fmtp
Purpose: Indicate the maximum transmission rate that an endpoint is willing to receive on a T.140 data channel.
Reference: [ RFC-to-be ]

As this document requests registrations in an Expert Review or Specification Required (see RFC 8126) registry, we will initiate the required Expert Review via a separate request. This review must be completed before the document's IANA state can be changed to "IANA OK."

Third, also in the att-field registry on the Session Description Protocol (SDP) Parameters registry page located at:

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

the existing registrations for the attributes hlang-send and hlang-recv are to be modified in accordance with [draft-ietf-mmusic-rfc4566bis] as follows:

Usage level: dcsa(t140)
Attribute name: hlang-send
Purpose: Negotiate the language to be used on a T.140 data channel.
Reference: [ RFC-to-be ]

Usage level: dcsa(t140)
Attribute name: hlang-recv
Purpose: Negotiate the language to be used on a T.140 data channel.
Reference: [ RFC-to-be ]

As this also requests registrations in an Expert Review or Specification Required (see RFC 8126) registry, we will initiate the required Expert Review via a separate request. This review must be completed before the document's IANA state can be changed to "IANA OK."

Fourth, also in the att-field registry on the Session Description Protocol (SDP) Parameters registry page located at:

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

the existing registrations for the attributes sendonly, recvonly, sendrecv and inactive are to be modified in accordance with [draft-ietf-mmusic-rfc4566bis] as follows:

Usage level: dcsa(t140)
Attribute name: sendonly
Purpose: Negotiate the direction in which real-time text can be sent on a T.140 data channel.
Reference: [ RFC-to-be ]

Usage level: dcsa(t140)
Attribute name: recvonly
Purpose: Negotiate the direction in which real-time text can be sent on a T.140 data channel.
Reference: [ RFC-to-be ]

Usage level: dcsa(t140)
Attribute name: sendrecv
Purpose: Negotiate the direction in which real-time text can be sent on a T.140 data channel.
Reference: [ RFC-to-be ]

Usage level: dcsa(t140)
Attribute name: inactive
Purpose: Negotiate the direction in which real-time text can be sent on a T.140 data channel.
Reference: [ RFC-to-be ]

As this also requests registrations in an Expert Review or Specification Required (see RFC 8126) registry, we will initiate the required Expert Review via a separate request. This review must be completed before the document's IANA state can be changed to "IANA OK."

The IANA Functions Operator understands 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.

Thank you,

Sabrina Tanamal
Senior IANA Services Specialist

The following Last Call announcement was sent out (ends 2020-02-06):

From: The IESG
To: IETF-Announce
CC: mmusic-chairs@ietf.org, adam@nostrum.com, mmusic@ietf.org, draft-ietf-mmusic-t140-usage-data-channel@ietf.org, Flemming Andreasen , fandreas@cisco.com
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (T.140 Real-time Text Conversation over WebRTC Data Channels) to Proposed Standard


The IESG has received a request from the Multiparty Multimedia Session
Control WG (mmusic) to consider the following document: - 'T.140 Real-time
Text Conversation over WebRTC Data Channels'
  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 2020-02-06. 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 specifies how a WebRTC data channel can be used as a
  transport mechanism for Real-time text using the ITU-T Protocol for
  multimedia application text conversation (Recommendation ITU-T
  T.140), and how the SDP offer/answer mechanism can be used to
  negotiate such data channel, referred to as T.140 data channel.  The
  document updates RFC 8373.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-mmusic-t140-usage-data-channel/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-mmusic-t140-usage-data-channel/ballot/


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

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?

Proposed Standard. The intended status is shown as “Standards Track”, which is appropriate since the document updates RFC 8373 and defines how to signal “T.140 over WebRTC Data Channels” in the Session Description Protocol (SDP).

(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:

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.

The document specifies how a WebRTC data channel can be used as a transport mechanism for Real-time text using the ITU-T Protocol for multimedia application text conversation (Recommendation ITU-T T.140), and how the SDP offer/answer mechanism can be used to negotiate such data channel, referred to as T.140 data channel.  The document updates RFC 8373.

Working Group Summary:

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?

No controversy or other concerns. The document has progressed remarkably quickly in the WG, while at the same time seen good discussion and participation from several people.

Document Quality:

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?

There are existing implementations of the WebRTC data channels, however we are not aware of implementations for the T.140 data channel usage

Gunnar Hellström provided very good comments and input

Additional expert reviews are not needed.

Personnel:

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

Flemming Andreasen is the Documenet Shepherd
Adam Roach 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.

I have reviewed -08 in detail as well as the subsequent changes up to -11 (the current version).


(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.

N/A

(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.

N/A

(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?

The author has confirmed

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

N/A

(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 document has seen decent WG participation in the document and there is solid consensus behind it.

(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.)

N/A

(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.

The document normatively references ITU-T T.140 and ITU-T T.140 Addendum 1, which is causing 2 comments. There are no other noteworthy nits.

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

There are no such extensions in the document and hence no formal reviews.

(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.

The document normatively references ITU-T T.140 and ITU-T T.140 Addendum 1, which causes a “possible downref” comment. However, since these are ITU-T Recommendations and hence considered “open external standards” per RFC 2026, this should not be an issue. 

(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.

The document updates RFC 8373, which is shown on the title page and called out in the Abstract and the Introduction

(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).

I have reviewed the IANA registrations in accordance with the above and found them to comply.

(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.

N/A

(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?

N/A

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?

Proposed Standard. The intended status is shown as “Standards Track”, which is appropriate since the document updates RFC 8373 and defines how to signal “T.140 over WebRTC Data Channels” in the Session Description Protocol (SDP).

(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:

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.

The document specifies how a WebRTC data channel can be used as a transport mechanism for Real-time text using the ITU-T Protocol for multimedia application text conversation (Recommendation ITU-T T.140), and how the SDP offer/answer mechanism can be used to negotiate such data channel, referred to as T.140 data channel.  The document updates RFC 8373.

Working Group Summary:

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?

No controversy or other concerns. The document has progressed remarkably quickly in the WG, while at the same time seen good discussion and participation from several people.

Document Quality:

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?

There are existing implementations of the WebRTC data channels, however we are not aware of implementations for the T.140 data channel usage

Gunnar Hellström provided very good comments and input

Additional expert reviews are not needed.

Personnel:

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

Flemming Andreasen is the Documenet Shepherd
Adam Roach 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.

I have reviewed -08 in detail as well as the subsequent changes up to -11 (the current version).


(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.

N/A

(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.

N/A

(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?

The author has confirmed

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

N/A

(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 document has seen decent WG participation in the document and there is solid consensus behind it.

(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.)

N/A

(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.

The document normatively references ITU-T T.140 and ITU-T T.140 Addendum 1, which is causing 2 comments. There are no other noteworthy nits.

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

There are no such extensions in the document and hence no formal reviews.

(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.

The document normatively references ITU-T T.140 and ITU-T T.140 Addendum 1, which causes a “possible downref” comment. However, since these are ITU-T Recommendations and hence considered “open external standards” per RFC 2026, this should not be an issue. 

(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.

The document updates RFC 8373, which is shown on the title page and called out in the Abstract and the Introduction

(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).

I have reviewed the IANA registrations in accordance with the above and found them to comply.

(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.

N/A

(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?

N/A