Shepherd writeup

RFC1981bis Writeup

Title           : Path MTU Discovery for IP version 6
Authors         : Jack McCann <>
                  Stephen E. Deering <>
                  Jeffrey Mogul <>
                  Robert M. Hinden, Editor
Filename        : draft-ietf-6man-rfc1981bis-03.txt
Pages           : 17
Date            : 2016-10-04

(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

   Internet Standard

   RFC1981 is currently at Draft Standard, the 6MAN working group has
   reached a consensus that it’s time to elevate the Path MTU Discovery
   for IP version 6 specification to Internet Standard.

   The header indicates “Standards Track”.

(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 describes Path MTU Discovery for IP version 6.  It is
   largely derived from RFC 1191, which describes Path MTU Discovery for
   IP version 4.  It obsoletes RFC1981.

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?

   The 6MAN working started working on advancing the IPv6 core
   specifications to Internet Standard at IETF93 July 2015.  See: The
   working group identified three RFCs to update (RFC2460, RFC4291, and
   RFC1981) by incorporating updates from other RFCs and Errata, and
   three to advance in place RFC4443, RFC3596, and RFC4941.  After
   further analysis, the w.g. decided to not reclassify RFC4941 at this
   The working followed the requirements in RFC6410 for advancing a Draft
   Standard to Internet Standard.  While RFC6410 describes how to handle
   Errata, it doesn't say anything about Updated-By RFCs.  The working
   group, with the advice of our AD, incorporated the changes from the
   the Updated-By RFC and verified there was interoperability of the

   All of the Updated-By and errata were brought into the new draft in
   small steps to allow thorough review of all of the changes.  A summary
   and link to diff from the previous version was sent to the mailing
   list.  All of the changes to each draft were also discussed in detail
   at IETF94, IETF95, IETF96, and IETF97.  All of the changes from
   RFC1981 are summarized in Appendix B and are ordered by the Internet
   Draft that brought the change in.

   This document is an update to RFC1981 that was published prior to
   RFC2119 being published.  Consequently while it does use "should/must"
   style language in upper and lower case, the document does not cite the
   RFC2119 definitions.  Since the changes in this update were very
   limited, the w.g. concluded to not change any of this language.
   A working group last call for moving this and the other two documents
   to Internet Standard was started on 30 May 2016.  Reviews were also
   requested.  Issues found during the last call and reviews were entered
   into the 6MAN ticket system.  These are now closed.

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?

   IPv6 is implemented on most platforms (hosts, routers, servers, etc.),
   including proprietary and open source.  A list of products that have
   received the IPV6 Ready logo can be found at:

   Most major ISP now support IPv6, as well as many mobile

   Google’s IPv6 stats at show they are
   seeing now about 15% of their overall user traffic is IPv6. Country
   adoption is 29% in the US, Germany 27%, Finland 12%, Japan 14%, Brazil
   11%.  IPv6 users per AS can be found at

   The University of New Hampshire InterOperability Laboratory (UNH)
   analyzed the incorporated updates to insure they were implemented and
   interoperable.  No problems were found.  Their report can be found at:

   No MIB, Media, or other expert reviews are required.


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

   Document Shepherd: Ole Trøan
   Responsible AD: Suresh Krishnan

(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

   The document was reviewed by the Document Shepherd and believes it is
   ready for publication.

(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


(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?


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

   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?

   The document has had extensive review in the 6MAN working group and
   there is broad support to this version of the IPv6 specification as an
   Internet Standard.

(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 appeals have been threatened. 

(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

   Nothing serious.  A few miscellaneous warning about line spacing and
   notice that the reference to draft-ietf-6man-rfc2460bis is a down
   reference. Draft-ietf-6man-rfc2460bis will be submitted for Internet
   Standard with this draft.  Also, this document uses capitalized MUST,
   SHOULD, etc. language, but doesn't reference RFC2119 because it was
   originally written prior to RFC2119.

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


(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?

   The only normative reference this is not an RFC, is a reference to
   draft-ietf-6man-rfc2460bis. This draft is also being submitted to the
   IESG for Internet standard around the same time as this document.

(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.

   Nothing other than draft-ietf-6man-rfc2460bis discussed in the
   previous section.

(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 obsoletes RFC1981. This is indicated in the header and

(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).

    This document does not make any new assignments.

(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.