Shepherd writeup

Shepherd status: 
1) Holding on 2 IPR staements 
2) Awaiting revision -05.txt 
There are minor nits regarding the "yang tree diagrams" and the out-of-date 
references that have been sent off to authors as a revised XML. 
It is expected the authors will respond by 2/11.   

Shepherd's review required by: RFC 4858, template: 2/24/2012

(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?

Proposed standard.  Indicated on top of page header. 

(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 fabric topology in Data
   Center Network.

   Normally, a data center (DC) network is composed of single or
   multiple fabrics which are also known as PODs (Points Of Delivery).
   These fabrics may be heterogeneous due to implementation of different
   technologies when a DC network is upgraded or new techniques and
   features are enrolled.    The configuration and management of such DC networks with
   heterogeneous fabrics will result in considerable complexity,
   requiring a fair amount of sophistication.   As a basis for DC fabric management, 
   this document defines a YANG  data model [6020][7950] for fabric-based data center topology. 
   To do so, it augments the generic network and network topology data models
   defined in [I-D.ietf-i2rs-yang-network-topo] with information that is
   specific to Data Center fabric networks.

Working Group Summary

  There was solid consensus in the working group to take 
  on the work both on the list, and at IETF meetings. 
 There is an implementation of this yang data model. 

The WG LC call details can be found at:

Document Quality

  Are there existing implementations of the protocol?
  Yes - Huawei has an implementation of these protocol standards. 

  Have a significant number of vendors indicated their plan to 
  implement the specification? 

  Huawei is the vendor that has indicated implementation support. 

  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? 

 The routing directorate review by: Matthew Bocci at caused changes
 and the reviewer was satisfied with the changes: 

review (beginning of thread):

Reviewers Acks;

Yang Doctor's review by: Reshad Rahman (ready with issues) had the issues resolved.
The email track is:

No response from Reshad, but each of the issues was tracked by the shepherd. 


 Document Shepherd: Susan Hares
 AD: Alia Atlas 
 Routing QA Reviewer: Matthew Bocci
 Yang Doctors: Reshad Rahman 

(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.

Shepherd did the following: 
1) Walked through Yang reviewe guide: draft-ietf-netmod-rfc6087bis-17
2) Walk through each of the resolutions of the RTG-DIR-QA and Yang Doctors REview
3) Check the nits 
4) Check the latest yang tree diagram. 
4) Security consideration based on Yang guidelines were considered. 

The issue of the security of Data Center fabrics is dependent on the deployments. 
The data center fabrics may be utilized by tenants of a Data Center (e.g. Amazon data centers or 
 gooogle data centers), or by only private corporations with specific divisions. 
If the security ADs wish to have additional security considerations beyond the 
those of the Yang guidelines added to this document, the authors would 
welcome suggestions.   The Shepherd has flagged the Security ADs for this request. 

There are minor nits regarding the "yang tree diagrams" and the out-of-date 
references that have been sent off to authors as a revised XML. 
It is expected the authors will respond by 2/11.   

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

No, this has been cross-reviewed by TEAS and nvo03 before adoption. 
It was A reviewed by Yang Doctors and RTG-DIR QA review. 
See my comments above. 

(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.

It is a routing area YANG model, therefore it 
it will need Yang doctors, OPS-DIR, RTG-DIR review. 

(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.  The shepherd believes we have contacted all related WGs

(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.

Yan Zhuang

 Rong Gu

Hariharan Ananthakrishnan
(need IPR statement)

Danian Shi
(need IPR Statement) 

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

No 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?   

Solid active participation to adopt.  WG is closing own so the
energy in all last calls is slow. 

(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

Following nits: 
1)  overlong lines: 
     There are 16 instances of too long lines in the document, the longest
     one being 11 characters in excess of 72.
lines (245, 296, 304, 411, 433, 761, 817, 827, 1004, 1028, 1258, 1339, 1354, 1360, 1373, 1537, and 1538) - according to ID-Nits. 

2)  The NITs complains about no reference to the following documents: 
a) draft-ietf-i2rs-yang-l3-topology
b) draft-ietf-i2rs-yang-network-topo
3) draft-ietf-netmod-revised-datastores
4) draft-ietf-nvo3-vxlan-gpe

3) Yang tree diagram draft problem needs to be moved to normative. 

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

Reviewed against: 
draft-ietf-netmod-rfc6087bis - it appears to meet the guidelines to this draft. 
(note: The shepherd is not a Yang Doctor). 

(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?

 [I-D.draft-ietf-netmod-yang-tree-diagrams] - should be moved to normative.
It has past the IESG Review, and awaits a revised ID prior to heading to RFC editor. 

(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. 


(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 5226).

Yes - IANA has been reviewed per draft-ietf-netmod-rfc6087bis, and
per the IANA Guidelines RFC 8126. 

(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, etc.

Yang model checking (see draft header for results)