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Shepherd writeup

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 requested type of RFC is standard Track. This is appropriated to provide
interoperability. The type is indicate din the title.

(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.

   This document specifies a profile for the ACE (Authentication and
   Authorization for Constrained Environments) framework to enable
   authorization in an Message Queuing Telemetry Transport (MQTT)-based
   publish-subscribe messaging system.  Proof-of-possession keys, bound
   to OAuth2.0 access tokens, are used to authenticate and authorize
   MQTT Clients.  The protocol relies on TLS for confidentiality and
   MQTT server (broker) authentication.

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?

Nothing was special.

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 at least two known implementations:
 * Implementation using the HiveMQ CE is a Java-based open source MQTT broker
 that fully supports MQTT 3.x and MQTT 5.
* The Mosquitto prototype was only v3.1.1:


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

Daniel Migault is the shepherd, Ben Kaduk is teh 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 reviewed the document and have no special concerns I am considering the
document ready.

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


(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.


(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.


(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?


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


(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 went through several rounds of reviews. Though I came while the
document was already a WG document. I have the impression that the number of
reviewers were around 4.

(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.)


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

nits mentions the lack of the RFC 2119 boilerplate but the boiler template is
mentioned in section 1.1

draft-ietf-ace-aif is a normative reference which is appropriated as it defines
the data model of MQTT in section 3.

draft-ietf-cose-x509 is a normative reference as it defines the format of the
rs_cnf and procedure to check it.

'MQTT-OASIS-Standard' and 'MQTT-OASIS-Standard-v5' define the MQTT document
that is the subject of our document. While our document is mostly focused on an
integrating MQTT to ACE, MQTT is defined by OASIS and fields of the protocol
are defined in OASIS. I believe these document should be normative.

draft-ietf-ace-pubsub-profile current version is effectively 01 so there might
be an error in the nits tool.

idnits 2.16.04


  Checking boilerplate required by RFC 5378 and the IETF Trust (see

     No issues found here.

  Checking nits according to

     No issues found here.

  Checking nits according to :

     No issues found here.

  Miscellaneous warnings:

  == The document seems to lack the recommended RFC 2119 boilerplate, even if
     it appears to use RFC 2119 keywords.

     (The document does seem to have the reference to RFC 2119 which the
     ID-Checklist requires).

  Checking references for intended status: Proposed Standard

     (See RFCs 3967 and 4897 for information about using normative references
     to lower-maturity documents in RFCs)

  == Missing Reference: 'RFC-XXXX' is mentioned on line 1095, but not defined

  ** Downref: Normative reference to an Informational draft:
     draft-ietf-ace-aif (ref. 'I-D.ietf-ace-aif')

  -- Possible downref: Non-RFC (?) normative reference: ref.

  -- Possible downref: Non-RFC (?) normative reference: ref.

  -- Unexpected draft version: The latest known version of
     draft-ietf-ace-pubsub-profile is -00, but you're referring to -01.

     Summary: 1 error (**), 0 flaws (~~), 2 warnings (==), 3 comments (--).

     Run idnits with the --verbose option for more detailed information about
     the items above.


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


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


(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?

yes. wait the normative document are completed.

(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

Some are downward normative references as the mention standard that are part of
other SDO (OASIS).  See comments related to the nits.

(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.


(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 shepherd checked the requested code points in the document be mentioned in
the IANA as well as the procedure for registering these code points followed:

Registration of the 'EXPORTER-ACE-MQTT-Sign-Challenge' in the TLS Exporter
Label Registry is described in [RFC8447]. Request has been sent to the bu Cigdem on 2020 November 1 and approved by Rich and

Registration of 'mqtt_tls' is in the ACE OAuth Profile Registry is specified in
[I-D.ietf-ace-oauth-authz] and require providing a template that has been added
in the IANA section.

(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.


(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.

rfc nits.

(20) If the document contains a YANG module, has 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