Autonomic IPv6 Edge Prefix Management in Large-Scale Networks
draft-ietf-anima-prefix-management-07

[Ballot comment]
- On my first reading, I wondered why this was informational. It seems to seek to standardize protocol elements. The explanation in the shepherd report clarifies that; it would be helpful to include (a perhaps shortened version of) that in the draft.

-2: RFC 8174 has boilerplate to address the "only in upper case" part. Please consider using it rather than modifying the 2119 boilerplate.

-4.4: "It is therefore important to record all the prefix assignment history."
Isn’t this a local policy choice? Perhaps some operator believes in extreme log minimization, does this mean to argue they are mistaken?

[Ballot comment]
Thank you.

I did have some comments / questions.
I'd also like to draw both the authors, and AD's attention to Fred Bakers excellent thoughts in his OpsDir review - https://datatracker.ietf.org/doc/review-ietf-anima-prefix-management-06-opsdir-lc-baker-2017-10-23/

Firstly, a global concern:
This technique (and I suspect many automated prefix allocations where a device uses space, and then requests more) is likely (I think) to result in fragmentation of the address space - this will lead to more routing entries in the IGP, which may be an issue for smaller routers or "L3 switches". I think that it would be useful to note this.

I also wanted to make sure that the author of this document were aware of the CASM BoF from IETF98 - I've just checked, and see that at least Qiong Sun was associated with the work (draft-xie-ps-centralized-address-management).

I had a question -- I don't really understand what: [Page 9] "A gateway router in a hierarchical network topology normally provides prefixes for routers within its subnet, ..." is trying to say. I've seen many "hierarchical network topologies" and don't believe this to be true, nor do I really understand what "its subnet" means. In some cases a router will announce an aggregate for customers behind it, but I don't really view that as a general case. I'm guessing I'm just not understanding - can you please educate me?

[Ballot comment]
Thank you.

I did have some comments / questions.

Firstly, a global concern:
This technique (and I suspect many automated prefix allocations where a device uses space, and then requests more) is likely (I think) to result in fragmentation of the address space - this will lead to more routing entries in the IGP, which may be an issue for smaller routers or "L3 switches". I think that it would be useful to note this.

I also wanted to make sure that the author of this document were aware of the CASM BoF from IETF98 - I've just checked, and see that at least Qiong Sun was associated with the work (draft-xie-ps-centralized-address-management).

I had a question -- I don't really understand what: [Page 9] "A gateway router in a hierarchical network topology normally provides prefixes for routers within its subnet, ..." is trying to say. I've seen many "hierarchical network topologies" and don't believe this to be true, nor do I really understand what "its subnet" means. In some cases a router will announce an aggregate for customers behind it, but I don't really view that as a general case. I'm guessing I'm just not understanding - can you please educate me?

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

The IANA Services Operator has completed its review of draft-ietf-anima-prefix-management-05. If any part of this review is inaccurate, please let us know.

We understand that some of the actions requested in the IANA Considerations section of this document are dependent upon the approval of and completion of IANA Actions in another document: [ I-D:ietf-anima-grasp ]

The IANA Services Operator understands that, upon approval of this document, there is a single action which we must complete.

In the GRASP Objective Names Table registry to be created upon approval of the Internet Draft [ I-D:ietf-anima-grasp ], two new registrations are to be made as follows:

Name: PrefixManager
Reference [ RFC-to-be ]

Name: PrefixManager.Params
Reference [ RFC-to-be ]

Because this registry requires Expert Review [RFC8126] for registration, we'll contact the IESG-designated expert in a separate ticket to request approval. Expert review should be completed before your document can be approved for publication as an RFC.

The IANA Services Operator understands that this is the only action 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 only to confirm what actions will be performed.


Thank you,

Sabrina Tanamal
IANA Services Specialist

The following Last Call announcement was sent out (ends 2017-10-12):

From: The IESG
To: IETF-Announce
CC: tte+anima@cs.fau.de, anima-chairs@ietf.org, Toerless Eckert , draft-ietf-anima-prefix-management@ietf.org, anima@ietf.org, terry.manderson@icann.org
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (Autonomic IPv6 Edge Prefix Management in Large-scale Networks) to Informational RFC


The IESG has received a request from the Autonomic Networking Integrated
Model and Approach WG (anima) to consider the following document: -
'Autonomic IPv6 Edge Prefix Management in Large-scale Networks'
  as Informational RFC

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
ietf@ietf.org mailing lists by 2017-10-12. 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 describes an autonomic solution for IPv6 prefix
  management at the edge of large-scale ISP networks, with an extension
  to support IPv4 prefixes.  An important purpose of the document is to
  use it for validation of the design of various components of the
  autonomic networking infrastructure.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-anima-prefix-management/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-anima-prefix-management/ballot/

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

  https://datatracker.ietf.org/ipr/3026/
  https://datatracker.ietf.org/ipr/3027/

Version 02 of shepherd review as of 08/26/2017 against
draft-ietf-anima-prefix-managemenet-05
Toerless Eckert

| 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)?

Informational

| (1b) Why is this the proper type of RFC?

In the current ANIMA charter,

network.https://datatracker.ietf.org/doc/charter-ietf-anima/

the primary goal is to develop protocol specifications (standards track),
which have become GRASP, BRSKI and ACP.

In addition, there are two "use case validation" documents. This is one
of them:

> (from the charter)
> In addition, the WG will validate the application and reusability of the
> components to the following two use cases:
> o A solution for distributed IPv6 prefix management within a large-scale
>  network

The validation drafts are primarily meant to validate the applicability,
benefits and sufficiency of the protocol specification to build solutions.
The validation documents are not meant to establish actual standards for
these solutions. To be more precise for this document:

- This document primarily shows in detail how GRASP can be used to
  signal/negotiate with the example of address delegation negotiation.
  It also describes to rely on ACP for security and availability of flooding
  services from GRASP. This is the core purpose of the document.

- This document outlines approaches how to build an overall
  system to do this. This is not meant to establish a standard
  but is purely informational:

  - To build an overall ANIMA address prefix management solution,
    we would first need to specify expectations against ASA and
    intent. These two pieces are not yet part of the charter.
 
  - There are many ways to build such a system, and we expect that
    any acutally standardized solution for address management could
    potentially be subject to a lot more work in a working group
    focussed on such a topic.

| (1c) Is this type of RFC indicated in the | title page header?

Yes

| (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 describes an autonomic solution for IPv6 prefix
  management at the edge of large-scale ISP networks, with an extension
  to support IPv4 prefixes.  An important purpose of the document is to
  use it for validation of the design of various components of the
  autonomic networking infrastructure.

| 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-jiang-anima-prefix-management
prior to its adoption. There was consenus support for it in favor of
adoption, so this document was adopted in January 2016. There was
interest in this work posts since its adoption. There was no opposition
to this work.
 
This document went through a relevant long document development
period (15 months for individual document period,  30 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 review by multiple WG participants.
Huawei has expressed interest in implementation.
There is a prototype implementation at:
https://github.com/becarpenter/graspy/blob/master/pfxm3.pdf
https://github.com/becarpenter/graspy/blob/master/pfxm3.py

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

Toerless Eckert 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.

Shepherd review was initially performed via the following mail to the list:
https://www.ietf.org/mail-archive/web/anima/current/msg02722.html

Beside a couple of minor points, the primary area of concern of the
shepherd was more explicit illustration of the system level setup (who
talks with whom, and where are they in the network). The spherd suggested
possible text.

The ensuing discussion on the mailing lists resulted in -04 see
summary in this email:

https://www.ietf.org/mail-archive/web/anima/current/msg02786.html

The shepherd thinks this version is ready for IESG review.

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

No.

| (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.

Because this is a concept, informational document, i think that
further review by other WGs is not necessary.

| (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.

I do not think there are any outstanding issue.
The authors are going to post one more version with one
late encoding detail being fixed.

| (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.

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

https://datatracker.ietf.org/ipr/3026/
https://datatracker.ietf.org/ipr/3027/

There was discussion on the mailing list about this disclosure
(only 3027 is relevant). No concerns where raised that this IPR
claim would impac 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
participants. There where no controversies but instead ongoing
refinement through feedback (aka: very collaborative).

| (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.

No nits.
IMHO, no document issues given the intended purpose of the document as outlined above.

| (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?

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?

Yes. Those documents are (a subset) of the ANIMA protocol drafts,
specifically GRASP. These are all in process of being 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 procedure.

No downward normative references. This document is informational.

| (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 change to 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 add two names to GRASP Objective Names Table
registry defined by [I-D.ietf-anima-grasp] (registry already crated).
"PrefixManager" and "PrefixManager.Params". I did review/discuss these
names during shepherd review. I think these allocations establish
a useful precedent of making multiple objectives of one functional area
use a common prefix.

| (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.

Visual verification of the JSON and CDDL [I-D.greevenbosch-appsawg-cbor-cddl]
sections in the document. No automated tools identified.