Shepherd writeup
rfc7499-12

PROTO write-up for draft-ietf-radext-radius-fragmentation-08
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(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 document is aiming for Experimental status. This is the correct choice because it 
proposes complex changes to the RADIUS operational model to achieve transmission 
of payload sizes beyond the current maximum (4096 bytes). It aims for backward 
compatibility when being transmitted over legacy intermediate proxy systems which are
 not yet upgraded to support the requirements of this document. The real-life suitability 
of these changes needs further study; hence Experimental. There are other 
approaches to the same problem discussed in the working group, but they are not 
backwards compatible to non-upgraded proxies.

(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:

   The Remote Authentication Dial-In User Service (RADIUS) protocol is
   limited to a total packet size of 4096 octets.  Provisions exist for
   fragmenting large amounts of authentication data across multiple
   packets, via Access-Challenge.  No similar provisions exist for
   fragmenting large amounts of authorization data.  This document
   specifies how existing RADIUS mechanisms can be leveraged to provide
   that functionality.  These mechanisms are largely compatible with
   existing implementations, and are designed to be invisible to
   proxies, and "fail-safe" to legacy clients and servers.

Working Group Summary:

   The content of this document was discussed at length in the working
   group, and there are multiple other approaches to the same problem.
   The document thus got significant exposure at the experts of the
   working group. The document has a few rough edges which were the cause
   of discussions. Considering the target status of Experimental, they
   appear minor enough to carry on with the experiment. The authors have
   documented the friction points in their section 11 "Operational
   Considerations". 11.1 in particular shows a process question: is it
   appropriate for an Experimental RFC to update a Standards-track RFC?
   The document attempts to follow that course; if this is ultimately
   agreed after IESG review, the text in that section will be changed
   accordingly.

Document Quality:

   At least one implementation is known which implements this
   specification: FreeRADIUS. The sheperd has no information about plans of
   other vendors. There were no particular expert reviews outside the
   working group process; i.e. no MIB doctor review nor Media Type review
   (and no need for those two as the document contains neither MIBs nor 
   requests a Media Type). Since the document adds new transport
   capabilities, a thorough review by transport experts (e.g. TSVDIR) during
   IETF Last Call would be appreciated.

Personnel:

   The Document Shepherd is Stefan Winter <stefan.winter@restena.lu>. The 
   responsible Area Directors are Benoit Claise <​bclaise@cisco.com> and Joel
   Jaeggli <​joelja@bogus.com>.

(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 sheperd was actively reviewing the document during its entire lifecycle, back then 
as individual participant in the WG (now chair). For the PROTO write-up, he gave the 
then-latest version -06 a fresh read; which resulted in a number of minor changes 
which are now the -08 version which is ready for advancement in the publication 
process.

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

No concerns; the document was read by and commented on by a comparatively high
 number of participants.

(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.

The document addresses a very specific RADIUS shortcoming and this document's 
impact does not appear to matter from a broader perspective at first glance. However, 
the document introduces a new transport property for RADIUS (fragmentation support)
 which deserves a close look by transport area experts. There may be issues with 
traversing AAA proxies which are unaware of this document, but those issues have 
been uncovered during the WG review process and are enumerated in section 11.

(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.

The issue described in 11.1 had no final conclusive answer; i.e. is it better to a) have 
this document update a standards-track document, or b) have an IANA registry for the 
flag field assignments, or c) just do nothing. The working group consensus went for a), 
which is fine IMO, but the text in 11.1 will need to be updated with more confident 
language once it is determined if that course of action is acceptable process-wise.

From a more general point of view, the entire solution is rather bulky and not very 
elegant; but it solves an actual problem and operates despite possible presence of 
unaware proxies on the path, which is a significant plus.

(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?

During the PROTO Write-Up, the sheperd asked each author and they all confirmed 
that they have no outstanding IPR disclosures.

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

There was no IPR disclosure.

(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 is one group of individuals which was pushing for this document: the ABFAB WG 
and implementers of the corresponding specs needed this solution and so far, use 
cases beyond ABFAB have yet to surface. Naturally, these participants were most 
active and drove most of the discussions. However, more participants than just those 
were reviewing and commenting on the document, so there is solid consensus behind 
the document.

(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.)

There was one individual who expressed major disconsent during the call for adoption,
and also on various design choices before and after adoption. There was no threat of 
appeal though.

(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.

"The 'Updates: ' line in the draft header should list only the _numbers_
     of the RFCs which will be updated by this document (if approved); it
     should not include the word 'RFC' in the list."

There is a dangling reference [IANA-CONSIDERATIONS] (section pointer) which
can be fixed later in the publication process.

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

There are no MIBs, media types, or URI requests in 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?

All normative references are issued 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 procedure.

There are no downward normative references (1 x Informational, 2 x BCP, 3 x standards-track).

(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.

This document updates RFC6929. That document is mentioned in the introduction, but 
not the abstract. The reason why it is omitted in the abstract is because the relationship
 is relatively minor (a previously reserved flag is defined for use in this document) and 
because there are two dedicated sections (8 + 11.1) which explain the update 
relationship in considerable detail.

(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 document introduces two new attributes, one new value for an existing attribute, 
and a registry for an enumeration of values for one of those new attributes. The IANA 
consideration section contains all the info required by IANA to perform the reservations 
in question. Future allocations of the new registry are defined (RFC required). The 
name for the registry ('RADIUS Frag-Status "Code" registry') is reasonable.

(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.

The new registry is 'RFC required'; no experts needed.

(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 formal language constructs in the document.
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