Comparison of Network Management Datastore Architecture (NMDA) Datastores
draft-ietf-netmod-nmda-diff-12

[Ballot comment]
In Section 7:

"... number of requests that is served to a client ..." -- s/is/are/

Also, it strikes me that some of what's in Section 7 is repeated in the last paragraph of Section 9.  I wonder if they could perhaps be merged, or 9 could reference 7, or something.

[Ballot comment]
Thanks to Alexey Melnikov for the SECDIR review.

** Section 4.  “differences” bullet.  Per “… defined in RFC8072”, please make “RFC8072” an reference.

** Section 6.  Please review Alexey’s feedback on providing an empty line between the HTTP header and playload.

** Section 6.  “same request in RESTCONF (using JSON format)”.  Missing “:” making the JSON invalid.

OLD
  { "ietf-nmda-compare:input" {

NEW
  { "ietf-nmda-compare:input": {

** Section 9.  The primary new security issue is definitely the possibility of a denial of service as is documented.  I’m not sure what assumption are being made about the datastores -- would it be possible that a user doesn’t have read access to either the source and target of the comparison, but would be able to invoke the RPC?  If so, this might leak configuration information.

[Ballot comment]
All comments below are about very minor potential issues that you may choose to
address in some way - or ignore - as you see fit. Some were flagged by
automated tools (via https://github.com/larseggert/ietf-reviewtool), so there
will likely be some false positives. There is no need to let me know what you
did with these suggestions.

Section 1. , paragraph 2, nit:
> s both applied configuration data as well as status and statistics. As a resu
>                                  ^^^^^^^^^^
Probable usage error. Use "and" after "both".

Section 6. , paragraph 2, nit:
> ormat): HTTP/1.1 200 OK Date: Thu, 26 Jan 2019 20:56:30 GMT Server: example-s
>                              ^^^^^^^^^^^^^^^^
The date 26 Jan 2019 is not a Thursday, but a Saturday.

Uncited references: [RFC6991].

These URLs point to tools.ietf.org, which is being deprecated:
* http://tools.ietf.org/wg/netconf/

These URLs in the document can probably be converted to HTTPS:
* http://tools.ietf.org/wg/netconf/

[Ballot comment]
Thanks to Alexey Melnikov for the secdir review.

I'm not experienced enough with YANG to know whether or how problematic
it is that the "anydata subtree-filter" node contents are described by
reference to the NETCONF specification, which has a particular (XML)
representation of YANG data and does not give a clear presentation of
the abstract YANG structure/semantics to be used.  Is it possible to use
the filter-spec choice option when, for example, RESTCONF is used with
JSON encoding?

Section 4

  o  report-origin: When set, this parameter indicates that origin
      metadata should be included as part of RPC output.  When this
      parameter is omitted, origin metadata in comparisons that involve
      is by default omitted.

Why is it important to complicate the semantics of this parameter with a
dependence on the datastore?  It seems like it would be simpler to get
this effect by having clients specify report-origin when the target is
not .  Note that changing the semantics would require text
changes in subsequent parts of the document for consistency.  (If
retaining the current semantics, please clarify whether "comparisons
that involve " applies when operational is source, target,
or either.)

Section 9

In addition to noting that the "compare" RPC is sensitive and should be
restricted to authorized parties, I suggest to reiterate that the
"compare" operation should not provide a mechanism to work around access
control on other nodes -- that is, a result should only be returned if
the requestor would be allowed to access both the "source" and "target"
trees independently of the RPC.  In particular, even a "no-matches"
output should not be returned, as that might provide a way to determine
the structure of the datastore even without accessing it.

We might also incorporate by reference the security considerations for
subtree filtering (RFC 6241) and xpath filtering (RFC 6991).

NITS

Section 1

  an unusually long time to do so.  This can be the case due to certain
  conditions not being met, certain parts of the configuration not
  propagating because considered inactive, resource dependencies not
  being resolved, or even implementation errors in corner conditions.

"because considered inactive" seems like an incomplete clause; maybe
"because they are considered inactive"?

Section 4

  o  differences: This parameter contains the list of differences.
      Those differences are encoded per YANG-Patch data model defined in

s/YANG-Patch/the YANG-Patch/
I'd also consider s/per/according to/, since this is not exactly a
logic-driven deduction but rather more of a new requirement.

Section 6

  for the management of interfaces defined in [RFC8343].  The excerpt
  of the data model whose instantiation is the basis of the comparison
  is as follows:

I feel like this phrasing is a little misleading, as not only is the
following snippet only a subset of the nodes contained within "container
interfaces" but the descriptions have been greatly abbreviated as well.
Perhaps we could say something about "for the purposes of understanding
the subsequent example, the following subset of the [RFC8343] data model
is provided".

  Accept: application/yang-d

(I believe this truncated header field was already noted by another
reviewer.)

[Ballot comment]
[S5] [question]

* In the output yang-patch response when differences are present, is it
  theoretically possible that 'create' or 'insert' operations will need
  to be represented?  If not, why not?

[S{7,9}] [observation]

* The last paragraph of Section 9 and the whole of Section 7 seem to be
  saying the same things?  Perhaps consider if it's better to just say
  them once in Section 9 or say everything in Section 7 and just have
  the last paragraph of Section 9 say, in effect, "see also Section 7".

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

The IANA Functions Operator has completed its review of draft-ietf-netmod-nmda-diff-09. 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 two actions which we must complete.

First, in the ns registry on the IETF XML Registry page located at:

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

a new namespace will be registered as follows:

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

As this document requests registrations in a 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."

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

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

a new YANG module will be registered as follows:

Name: ietf-nmda-compare
File: [ TBD-at-Registration ]
Maintained by IANA? N
Namespace: urn:ietf:params:xml:ns:yang:ietf-nmda-compare
Prefix: cmp
Module:
Reference: [ RFC-to-be ]

While the YANG module name will be registered after the IESG approves the document, the YANG module file will be posted after the RFC Editor notifies us that the document has been published.

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 2021-07-02):

From: The IESG
To: IETF-Announce
CC: Joel Jaeggli , draft-ietf-netmod-nmda-diff@ietf.org, joelja@gmail.com, netmod-chairs@ietf.org, netmod@ietf.org, rwilton@cisco.com
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (Comparison of NMDA datastores) to Proposed Standard


The IESG has received a request from the Network Modeling WG (netmod) to
consider the following document: - 'Comparison of NMDA datastores'
  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 2021-07-02. 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 an RPC operation to compare management
  datastores that comply with the NMDA architecture.




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


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

  https://datatracker.ietf.org/ipr/3084/

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?

This is a standards track document requesting the status of proposed standard.

(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 an RPC operation to compare management datastores that comply with the (NMDA) Network Management Datastore Architecture architecture.

Working Group Summary:

NMDA diff attracted as significant amount of discussion due to the utility of being able to compare two datastores. As a result of this effort we believe that the working group connesenus reflects broad support for the current draft.

Document Quality:

The Document has been fairly widely reviewed. we believe that Yang Doctor  review, to be requested at the time of publication requested will constitute additional review.

Personnel:

Joel Jaeggli is the Shepherd Robert Wilton is the responsible AD

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

The document shepherd  reviewed draft 03  at the time of WG LC, and draft 04 changes reflecting WG consensus during last call.

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

No concerns about quality of document are currently present.

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

No

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

(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 WG chair confirms that, netmod adoption and WG LC IPR solicitations have been made. The WG chair is not aware of any IPR claims that have resulted from these requests.

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

The shepherd is not aware of any IPR claims.

(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?

WG consensus is in favor of advancing this document as the facility  is necessary.

(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 appeals are currently anticipated.

(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.

Nits complains about the formatting of  one line with the yang datamodel. it's cosmetic.

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

The document is submitted to yang doctors.

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

Normative and informative references are correctly identified.

(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?

The document is ready to advance.

(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.

normative references are to proposed standard / Standard and BCP documents.

(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 does not request status changes for existing documents.

(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).

This document registers one URI in the IETF XML registry  line 621-625

621       URI: urn:ietf:params:xml:ns:yang:ietf-nmda-compare

623       Registrant Contact: The IESG.

625       XML: N/A, the requested URI is an XML namespace.

This document registers a YANG module in the YANG Module Names registry line 633-637

633       name: ietf-nmda-compare

635       namespace: urn:ietf:params:xml:ns:yang:ietf-nmda-compare

637       prefix: cp

(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.

Basic yang validation passes.

(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?

Yes

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?

This is a standards track document requesting the status of proposed standard.

(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 an RPC operation to compare management datastores that comply with the (NMDA) Network Management Datastore Architecture architecture.

Working Group Summary:

NMDA diff attracted as significant amount of discussion due to the utility of being able to compare two datastores. As a result of this effort we believe that the working group connesenus reflects broad support for the current draft.

Document Quality:

The Document has been fairly widely reviewed. we believe that Yang Doctor  review, to be requested at the time of publication requested will constitute additional review.

Personnel:

Joel Jaeggli is the Shepherd Robert Wilton is the responsible AD

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

The document shepherd  reviewed draft 03  at the time of WG LC, and draft 04 changes reflecting WG consensus during last call.

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

No concerns about quality of document are currently present.

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

No

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

(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 WG chair confirms that, netmod adoption and WG LC IPR solicitations have been made. The WG chair is not aware of any IPR claims that have resulted from these requests.

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

The shepherd is not aware of any IPR claims.

(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?

WG consensus is in favor of advancing this document as the facility  is necessary.

(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 appeals are currently anticipated.

(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.

Nits complains about the formatting of  one line with the yang datamodel. it's cosmetic.

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

The document is submitted to yang doctors.

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

Normative and informative references are correctly identified.

(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?

The document is ready to advance.

(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.

normative references are to proposed standard / Standard and BCP documents.

(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 does not request status changes for existing documents.

(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).

This document registers one URI in the IETF XML registry  line 621-625

621       URI: urn:ietf:params:xml:ns:yang:ietf-nmda-compare

623       Registrant Contact: The IESG.

625       XML: N/A, the requested URI is an XML namespace.

This document registers a YANG module in the YANG Module Names registry line 633-637

633       name: ietf-nmda-compare

635       namespace: urn:ietf:params:xml:ns:yang:ietf-nmda-compare

637       prefix: cp

(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.

Basic yang validation passes.

(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?

Yes