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Shepherd writeup

Document Writeup, template from IESG area on, dated January 19, 2017.

draft-ietf-anima-autonomic-control-plane-13 write-up

(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 document defines a so-call "Autonomic Control Plane", 
   with the primary use as a control plane for autonomic functions. It is 
   self-managing and zero configuration for basic scenarios.
(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 defines a so-call "Autonomic Control Plane",  with the primary 
   use as a control plane for autonomic functions. It is  self-managing and zero
   configuration for basic scenarios.

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? 

  This document was called draft-behringer-anima-autonomic-control-plane  prior 
  to its adoption. There was unanimous support for it in favor of adoption and 
  none against, so this document was adopted in August 2015. There was 
  interest in this work posts since its adoption. There was never any 
  opposition for this work.

  This document went through a relevant long document development
  period (10 months for individual document period, 29 month for WG 
  document period). It has been reviewed well.

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, 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? 

  This document went through multiple reviews by multiple participants.
  There are multiple implementations of ACP. There is a commercial 
  implementation by Cisco, and said it was (no information for the latest
  status) available on a wide range of Cisco IOS router platforms. However, 
  It may not be fully compatible with the current ACP document, given that 
  the implementation was started far early than the long process of ACP
  standard document reached the final stage. Huawei had some an 
  experiment implementation with linux ACP. It has done by a 
  collaboration project with an university. It is mainly a prototype that 
  has proved the functionalities of ACP.  It is not planned to be open source. 
  One more  prototype implementation is still in ongoing process by 
  Michael Richardson.

 Please see attached information provided by the ACP authors to the 
 shepherd about experience with one of the existing pre-standard 


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

  Sheng Jiang is the document shepherd.
  Terry Manderson 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.

  I reviewed this document thorough once for -09 versions (and had
  other minor comments from time to time):  
  The issues raised in my reviews were promptly addressed by authors
  in -09 and -10 version along with the comments from other ANIMA WG members.  
  This document -13 version is ready for publication in my opinion.
(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.

  There are no outstanding issues.

(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. The authors, Michael H. Behringer, Steinthor Bjarnason and Toerless Eckert 
  have confirmed in writing that they are not aware of any IPR, and that any and
  all appropriate IPR disclosures required for full conformance with the provisions 
  of BCP 78 and BCP 79 have already been filed.
(8) Has an IPR disclosure been filed that references this document? If so,
summarize any WG discussion and conclusion regarding the IPR disclosures.

  The working group chair, document shephred too, did notify the WG the existing 
  of this IPR disclosure multi-times, including the WGLC. No concerns where raised
  that this IPR claim would impact the ability to proceed adopting the mechanisms
   described in this document.
(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?

  There was broad support for this document. It was reviewed by active WG 
(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. There was unanimous support for this work and nobody raised any objections.
(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.

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

  No MIB Doctor, media type, URI type or similar apply to this document.
(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?

  No. All normative references are published RFCs.
(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


(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. This document does not update any existing RFCs.

(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).

  The IANA is requested to register the value AN_ACP and SRV.est to the GRASP 
  Objectives Names Table in the GRASP Parameter Registry.

  The IANA is requested to create an ACP Parameter Registry with currently one 
  registry table: the "ACP Address Type" Table (without quotes). In the "ACP 
  Address Type" Table, 2 intial values are assigned for "ACP Zone Addressing 
  Sub-Scheme" and "ACP Vlong Addressing Sub-Scheme" (without quotes).

  All the necessary information is in the IANA considerations document. It is
  clear enough that the IANA will be able to implement it.
(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 such registry is requested in this document.
(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.

  There are no such parts to the document.

Experience with a prototype implementation of GRASP confirms that a 
simple interface with the ACP, based on standard UDP and TCP sockets 
connected to the network interfaces provided by the ACP VRF, is necessary and sufficient.

The following information about use and deployment experience of the ACP
design was provided to the shepherd by the ACP authors:

The ACP specification draws a lot of experience and confidence in the
feasibility and value of the design from commercial implementations of
pre-standard implementations and their deployment.  It also draws experience
from open source implementations and design of components, for example 
the SNBI project in OpenDaylight, which also inherits some of the work done 
for one of the commercial implementations.

One series of commercial implementations specifically supports all the core aspects
of the ACP such as auto-configuration of the ACP as a separate VRF
protected from operator configuration, relying on a bootstrap provisioned domain
certificate to provide mutual authentication and authorization and domain name
derived ULA addressing for the ACP node itself. Also the RPL routing protocol
and its profile, and connectivity to non-ACP components via ACP connect interfaces.

Several aspects of the ACP did evolve from improving upon these pre-standard
experiences. This includes primarily the use of GRASP for neighbor discovery and
service/objective discovery across the ACP as opposed to a vendor proprietary
protocol and multi-hop DNS-SD inside the ACP. The GRASP and ACP authors think that
the choice of GRASP provides simplification, generalization and better mechanisms
for flooding densely used service information. This was backed by experiences with 
GRASP  reference implementations, also open source (see also shepherd writeup for GRASP).

The described certificate management for the ACP including the concept of registrar
likewise is based on implementation and large-scale ACP planning with customers and 
their CA infrastructure (often up to three layers).  Commercial implementations used 
where relying on the older SCEP enrollment protocol instead of the IETF standard EST 
(RFC7030) chosen for ACP certificate renewal.

Some enhancements over commercially available implementations where introduced
through the WG work, review and requirements raised. This includes address
auto-configuration of ACP interfaces, better structured/extensible encoding of
ACP attributes into the domain certificate and more addressing choices for the
ACP to better support various use-cases (large networks with multiple zones...
networks with ACP nodes that require many addresses inside the ACP).