A YANG Data Model for the Multicast Source Discovery Protocol (MSDP)
draft-ietf-pim-msdp-yang-18

[Ballot comment]
I'm assuming the sponsoring AD approved the presence of six authors on the document, exceeding our normal limit of five.

I'm a YANG newbie so for the moment I'm going to defer to those more expert at evaluating the syntax and semantics of the model described in Sections 3 and 4 while I go learn more about YANG in general.

Thus, the only feedback I have is editorial stuff in Section 5:
* "Modifying the configuration can cause MSDP default peers to be deleted or the connection to be rebuilt, and the SA's unexpected filtering." -- does that last clause mean "unexpected filtering by the SA"?
* "The key misoperation will broke the existed MSDP connection ... " -- s/broke the existed/break the existing/, right?
* "These are the subtrees and data nodes and their sensitivity/vulnerability:" followed by a list of one subtree/node.  Maybe just turn that into prose and name the singular subtree?
* "... may lead to forged connection attack, ..." -- s/to/to a/
* "... the ACL nodes uncorrected modification may lead to the filter errors." -- "nodes" should be "node's" or "nodes'"
* "The unauthorized reading function ..." -- perhaps "Unauthorized reads"?
* "... allow the unexpected peer connection rebuilding." -- maybe "allow the unexpected rebuilding of connection peers"?
* "Authentication configuration is supported ..." -- feels like this should start a new paragraph

[Ballot comment]
[ballot position under construction]

I'm assuming the sponsoring AD approved the presence of six authors on the document, exceeding our normal limit of five.

I'm a YANG newbie so for the moment I'm going to defer to those more expert at evaluating the syntax and semantics of the model described in Sections 3 and 4 while I go learn more about YANG in general.

Thus, the only feedback I have is editorial stuff in Section 5:
* "Modifying the configuration can cause MSDP default peers to be deleted or the connection to be rebuilt, and the SA's unexpected filtering." -- does that last clause mean "unexpected filtering by the SA"?
* "The key misoperation will broke the existed MSDP connection ... " -- s/broke the existed/break the existing/, right?
* "These are the subtrees and data nodes and their sensitivity/vulnerability:" followed by a list of one subtree/node.  Maybe just turn that into prose and name the singular subtree?
* "... may lead to forged connection attack, ..." -- s/to/to a/
* "... the ACL nodes uncorrected modification may lead to the filter errors." -- "nodes" should be "node's" or "nodes'"
* "The unauthorized reading function ..." -- perhaps "Unauthorized reads"?
* "... allow the unexpected peer connection rebuilding." -- maybe "allow the unexpected rebuilding of connection peers"?
* "Authentication configuration is supported ..." -- feels like this should start a new paragraph

[Ballot comment]
Thanks for the updates; they seem to address the core issues raised in my DISCUSS points.
That said, I do still have a couple additional requested changes.

With respect to authentication, I don't think we say much about how having an
authentication-type configured implies that the corresponding authentication type
is to be used at runtime (i.e., TCP-MD5 given the current state of things), and contrariwise
that the absence of a configured authentication type implies that unauthenticated TCP is used.

Also, for the leaf descriptions:

"up-time": "Indicates the duration of time since this SA entry was created in the cache. [...]"
"expire": "Indicates the duration of time until this SA entry in the cache will time out. [...]"

[Ballot comment]
I also support Ben’s DISCUSS.

Section 1.2 gives the BCP 14 boilerplate and references, but there are no BCP 14 key words in the document.  I suggest removing the boilerplate and the references.

[Ballot comment]
I only did a quick scan of this document.

I am not sure whether there are any I18N considerations for this leaf:
          case password {
            leaf key {
              type string;
              description
                "This leaf describes the authentication key.";
              reference
                "RFC 8177: YANG Data Model for Key Chains.";
            }

[Ballot discuss]
This yang modules makes use of RFC8177’s ietf-key-chain module.  Please add a reference to this draft inheriting RFC8177’s security considerations and associated considerations (see draft-ietf-ospf-yang for reusable language). 

Please also clarify the link between the password and RFC8177 per the following snippet of the YANG module in the Security Considerations.
    grouping authentication-container {
...
      container authentication {
        if-feature peer-authentication;
...
        choice authentication-type {
...
          }
          case password {

[Ballot discuss]
I don't think there's enough clarity on what authentication schemes are
supported and how the YANG configuration interacts with MSDP operation.
If I'm reading^Wsearching through RFC 3618 correctly, the only supported
authentication mechanism is TCP-MD5 (RFC 2385), and there have been no
updates to RFC 3618 that are indicated in the RFC database.  However,
RFC 2385 is obsoleted by RFC 5925 (TCP-AO).  Can TCP-AO be used with
MSDP?  What protocol elements or operation are controlled by the
"authentication" container?  What algorithms are valid for use with the
"password" case?  RFC 8177 is the sole reference for both the
"key-chain" leaf and the "password" case, but that does not seem a
sufficient reference from which to implement.

Also, there are a couple of elements in the "state-attributes" container
that say they indicate a time when something will/did happen and measure
it in seconds.  I don't see an indication of what the reference point is
for them, though -- "seconds since when?".  Further context in the
COMMENT to avoid too much quoted text here.

[Ballot comment]
This document (and the YANG module) lists six authors, which is more
than the typical five and would normally spark some discussion.  I do
see that the shepherd writeup indicates that all six members of the
design team were quite active, and presume that this indicates that it
is appropriate to have the larger author count than is typically seen.

Section 2.1

  This model can be used to configure and manage MSDP protocol.  The

nit: "the MSDP protocol".

Section 3.1

  MSDP configurations require peer configurations.  Several peers may

nit: this sentence on first read sounds like it is instantiating a
dependency loop ("my MDSP configuration depends on my peers' MSDP
configuration, which in turn depends on mine").  I suspect the intent is
to say something like "MSDP operation requires configuration information
that is distributed amongst several peers" or "MSDP operation requires
that all peers active in a given group receive identical configuration
information for that group" or similar.

Section 4

    grouping authentication-container {
          [...]
          case password {
            leaf key {
              type string;
              description
                "This leaf describes the authentication key.";
              reference

I'm not entirely sure what is being "described" -- if this is the
"password" choice (vs. key-chain), is it not the actual password itself
(versus a description thereof)?

            leaf crypto-algorithm {
              type identityref {
                base key-chain:crypto-algorithm;
              }
              description
                "Cryptographic algorithm associated with key.";

This is still in the "password" case, and I'm not entirely sure which
sorts of algorithms you're expecting to see here.  Things like
"hmad-sha-256" don't really apply directly to a password, and bare
hashes like sha-1 are cryptographically bad choices.

    grouping global-config-attributes {
        [...]
          "The default peer accepts all MSDP SA messages.
          A default peer is needed in topologies where MSDP peers
          do not coexist with BGP peers. The reverse path
          forwarding (RPF) check on SA messages can fail, and no
          SA messages are accepted. In these cases, you can configure
          the peer as a default peer and bypass RPF checks.";

nit: I think there could be a better connection between the sentences
here.  Is the need for default peer (in such topologies) due solely to
the potential for RPF failure?

        leaf peer-addr {
          type leafref {
            path "../../../peers/peer/address";

[Does this imply restrictions on where the grouping can be used in the
tree?]

      leaf mesh-group {
        type string;
        description
          "Configure this peer to be a member of a mesh group";
        reference
          "RFC 3618: Multicast Source Discovery Protocol (MSDP),
                    section 10.2.";
      }

This description leaves the reader rather unclear about what the
contents of this string-type leaf are supposed to be.

      leaf peer-as {
        [...]
          "Peer's autonomous system number (ASN). Using peer-as to
          do verification can provide more controlled ability.

nits: (1) more controlled than what?  (2) ability to do what?

          If the AS number is the same as the local AS, then the
          peer is within the same domain; otherwise, this peer is
          external to the domain. Like the definition and usage
          in BGP protocol.";

nit: "BGP protocol" is redundant.

site note: Both holdtime-interval and keepalive-interval have "must"
statements asserting that keepalive < holdtime when both are present.
Is it well-defined which one will trigger if an attempt is made to
violate the condition?  (The error message is the same for both, so this
is basically just for my personal edification.)

      leaf elapsed-time {
        type uint32;
        units seconds;
        config false;
        description "Elapsed time for being in a state.";
      }

Is this more properly a counter type than a uint32?

      leaf is-default-peer {
        type boolean;
        config false;
        description "'true' if this peer is a default peer.";

nit(?): how can there be more than one ("a") default peer?

      leaf reset-count {
        type uint32;
        config false;
        description "The reset count of this peer.";
      }

This one also sounds like it might be a counter.

      container statistics {

Please double-check for whether counter and/or gauge types might be more
appropriate than integer types.

            container state-attributes {
              description "SA cache state attributes for MSDP.";

              leaf up-time {
                type uint32;
                units seconds;
                description
                  "Indicates the time when this SA entry is created
                  in the cache. MSDP is a periodic protocol, the
                  up-time value can be used to check the state of
                  SA cache.";
              }
              leaf expire {
                type uint32;
                units seconds;
                description
                  "Indicates the time when this SA entry in the cache
                  times out. MSDP is a periodic protocol, the expire
                  value can be used to check the state of SA cache.";
              }

If these are "time" entries, that sounds like an absolute time.  If it's
measured in seconds, what is the reference point for that absolute time?

              leaf rpf-peer {
                type inet:ipv4-address;
                description
                  "The address is used to find the SA's
                  originating RP.";

"used to find" the originating RP or *is* the originating RP?  The name
would suggest the latter.

Section 5

      This subtree specifies the configuration for the MSDP attributes
      at the peer level.  The modification configuration will allow the
      unexpected MSDP peer establishment and unexpected SA information
      learning and advertisement.

nits: s/allow the unexpected/allow unexpected/; s/The modification
cofiguration/Modifying the configuration/.

      The "key" field is also a sensitive readable configuration, the
      unauthorized reading function may lead to the password leaking.
      The modification will allow the unexpected peer reconstruction.

I think it would be appropriate to mention that the key-chain choice
from RFC 8177 is designed to avoid this sort of vulnerabilities.
Also, nits: comma splice in the first sentence, and s/The
modification/Modification/.

Also^2, is this note better placed in the "readable data nodes" section
of the template?

  /rt:routing/rt:control-plane-protocols/msdp,

  Unauthorized access to any data node of the above subtree can
  disclose the operational state information of MSDP on this device.

It would be nice to go into a bit more detail about some of the
particularly important leaves under the msdp tree, and how knowing their
contents might aid an attacker.
E.g., the ACL nodes seem of particular interest (whether reading or
writing).

  Unauthorized access to any of the above action operations can
  reconstruct the MSDP peers or delete SA records on this device.

Will the reader know what "reconstruct the peer" means here (and the
operational/security impact of doing so)?

Section 9.1

It's not entirely clear to me that RFC 3688 is referenced in a normative
(as opposed to informative) manner.

Appendix A

Where does the 173.104.116.8 addrss come from?  I don't see it in RFC
5737 and it's not in the multicast range.
Likewise for 101/8.

It seems to me that the comments from the reviewers have been addressed.  I'm just waiting for the YANG Dr to confirm after the latest update.

The IETF LC concluded.  The authors are in the process of addressing some of the directorate reviews...and there are a couple more (GenArt + Ops) pending.

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

The IANA Functions Operator has completed its review of draft-ietf-pim-msdp-yang-08. If any part of this review is inaccurate, please let us know.

The IANA Services 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 single, new namespace will be registered as follows:

ID: yang:ietf-msdp
URI: urn:ietf:params:xml:ns:yang:ietf-msdp
Filename: [ TBD-at-Registration ]
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. Expert review will need to be completed before your document can be approved for publication as an RFC.

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

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

a single, new YANG module will be registered as follows:

Name: ietf-msdp
File: [ TBD-at-Registration ]
Maintained by IANA? N
Namespace: urn: urn:ietf:params:xml:ns:yang:ietf-msdp
Prefix: ietf-msdp
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 Services 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 2020-01-30):

From: The IESG
To: IETF-Announce
CC: stig@venaas.com, pim-chairs@ietf.org, aretana.ietf@gmail.com, Stig Venaas , pim@ietf.org, draft-ietf-pim-msdp-yang@ietf.org
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (A YANG Data Model for Multicast Source Discovery Protocol (MSDP)) to Proposed Standard


The IESG has received a request from the Protocols for IP Multicast WG (pim)
to consider the following document: - 'A YANG Data Model for Multicast Source
Discovery Protocol (MSDP)'
  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 2020-01-30. 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 YANG data model for the configuration and
  management of Multicast Source Discovery Protocol (MSDP) Protocol.




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

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-pim-msdp-yang/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 24 February 2012.

(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?
Standards track. The YANG model is for a widely deployed protocol. While the protocol is experimental, the model itself is not an experiment.

(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 YANG data model for the configuration and
management of the Multicast Source Discovery Protocol (MSDP) Protocol.

Working Group Summary
The WG has a YANG model design team. 6 member of the team (from a handful of vendors) have worked on this. It is based on implementations from these and other vendors. This indicates good vendor support. Aside from this, only 2 people supported the document for the WGLC, but none have raised any issues during the WGLC or in the WG otherwise.

Document Quality
A handful of vendors have worked on this and may be implementing it. 2 members of the WG have done a careful review, and a YANG doctor early review was also done.

Personnel
Stig Venaas is the shepherd, Alvaro Retana is the AD.

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

(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, except another YANG doctor review would be good.

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.
No concerns.

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.
Yes, each author has confirmed that they are not aware of any IPR, and no one else in the WG has mentioned any IPR. Also the contributors have stated that they are not aware of any IPR.

The WG was accidentally not copied when initially checking IPRs. The
responses the authors were summarized and posted in email
https://mailarchive.ietf.org/arch/msg/pim/7LBfuQAownskNm6jbX2LrgPpeq4

The 3 contributors responded, their responses were on the list in
these emails:
https://mailarchive.ietf.org/arch/msg/pim/3Arxn0ynwtA0xHL2v3htqJjlkHc
https://mailarchive.ietf.org/arch/msg/pim/fdIBYfHE7Q1_NOOdzhvw8siTtEc
https://mailarchive.ietf.org/arch/msg/pim/Pr_1Dt4N0iecqRYdKJJglJmE_VE

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.
No IPR

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 
At least 8 people are in support (6 of them authors), none are against. Wide range of vendors involved.
While we would have liked more people to review it, it is hard to get much responses to YANG models.

(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.
A few nits found by the tool, nothing major. Not aware of other nits.

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.
The early YANG doctor review only found minor issues, which should be addressed in version 06.

(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?
There are 2 normative references to YANG related documents. These will hopefully be published soon.

(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.
There are downward references to the MSDP protocol itself and the MSDP MIB. We still believe this document should be on the standards track though.

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.
No

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 8126).
The IANA considerations are clear and they are inline with other YANG models.

(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 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, etc.
No errors, but 2 warnings found by YANG validation tool.

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 24 February 2012.

(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?
Standards track. The YANG model is for a widely deployed protocol. While the protocol is experimental, the model itself is not an experiment.

(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 YANG data model for the configuration and
management of the Multicast Source Discovery Protocol (MSDP) Protocol.

Working Group Summary
The WG has a YANG model design team. 6 member of the team (from a handful of vendors) have worked on this. It is based on implementations from these and other vendors. This indicates good vendor support. Aside from this, only 2 people supported the document for the WGLC, but none have raised any issues during the WGLC or in the WG otherwise.

Document Quality
A handful of vendors have worked on this and may be implementing it. 2 members of the WG have done a careful review, and a YANG doctor early review was also done.

Personnel
Stig Venaas is the shepherd, Alvaro Retana is the AD.

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

(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, except another YANG doctor review would be good.

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.
No concerns.

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.
Yes, each author has confirmed that they are not aware of any IPR, and no one else in the WG has mentioned any IPR.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.
No IPR

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 
At least 8 people are in support (6 of them authors), none are against. Wide range of vendors involved.
While we would have liked more people to review it, it is hard to get much responses to YANG models.

(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.
A few nits found by the tool, nothing major. Not aware of other nits.

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.
The early YANG doctor review only found minor issues, which should be addressed in version 06.

(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?
There are 2 normative references to YANG related documents. These will hopefully be published soon.

(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.
There are downward references to the MSDP protocol itself and the MSDP MIB. We still believe this document should be on the standards track though.

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.
No

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 8126).
The IANA considerations are clear and they are inline with other YANG models.

(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 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, etc.
No errors, but 2 warnings found by YANG validation tool.

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 24 February 2012.

(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?
Standards track. The YANG model is for a widely deployed protocol. While the protocol is experimental, the model itself is not an experiment.

(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 YANG data model for the configuration and
management of the Multicast Source Discovery Protocol (MSDP) Protocol.

Working Group Summary
The WG has a YANG model design team. 6 member of the team (from a handful of vendors) have worked on this. It is based on implementations from these and other vendors. This indicates good vendor support. Aside from this, only 2 people supported the document for the WGLC, but none have raised any issues during the WGLC or in the WG otherwise.

Document Quality
A handful of vendors have worked on this and may be implementing it. 2 members of the WG have done a careful review, and a YANG doctor early review was also done.

Personnel
Stig Venaas is the shepherd, Alvaro Retana is the AD.

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

(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, except another YANG doctor review would be good.

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.
No concerns.

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.
Yes, each author has confirmed that they are not aware of any IPR, and no one else in the WG has mentioned any IPR.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.
No IPR

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 
At least 8 people are in support (6 of them authors), none are against. Wide range of vendors involved.
While we would have liked more people to review it, it is hard to get much responses to YANG models.

(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.
A few nits found by the tool, nothing major. Not aware of other nits.

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.
The early YANG doctor review only found minor issues, which should be addressed in version 06.

(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?
There are 2 normative references to YANG related documents. These will hopefully be published soon.

(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.
There are downward references to the MSDP protocol itself and the MSDP MIB. We still believe this document should be on the standards track though.

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.
No

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 8126).
The IANA considerations are clear and they are inline with other YANG models.

(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 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, etc.
No errors, but 2 warnings found by YANG validation tool.

Request for posting confirmation emailed to previous authors: Anish Peter , Xufeng Liu , Feng Guo , pim-chairs@ietf.org, Pete McAllister , Zheng Zhang , Mahesh Sivakumar

Request for posting confirmation emailed to previous authors: Anish Peter , Feng Guo , Xufeng Liu , pim-chairs@ietf.org, Pete McAllister , Zheng Zhang , Mahesh Sivakumar