Shepherd writeup

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)?  Why
is this the proper type of RFC?  Is this type of RFC indicated in the
title page header?

Proposed Standard. 

(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 Softwire mesh framework is a tunneling mechanism that enables
   the connectivity between islands of IPv4 networks across a single
   IPv6 backbone and vice versa.  In softwire mesh, extended
   multiprotocol-BGP (MP-BGP)is used to set up tunnels and advertise
   prefixes among address family border routers (AFBRs).  The softwire
   mesh MIB provides a method to configure and manage the softwire
   mesh objects through SNMP.

Working Group Summary

  The working group had active discussion on the draft and the current
  text of the draft is representative of the consensus of the working
  group. There were no controversial discussions regarding this

Document Quality

  The document has received adequate review. The Document Shepherd has
  no concerns about the depth or breadth of these reviews. There was a
  MIB doctor review that raised a few issues that have since been


  Suresh Krishnan 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 have reviewed several versions of this document. Earlier versions of
the document had some clear issues that needed to be fixed. So I
requested an early MIB doctor review. The issues have since been
(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.

The document needed specialized review from the MIB perspective and
the MIB doctor review by Dave Thaler provided that.

(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 MIB contained in the document produces two warnings with smilint
as described in Question 19. The MIB doctor review of this document in
version -03 did not contain any remarks about these warnings and I am
assuming this warning are benign. I just wanted to provide a heads
up to the OPS ADs.
(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


(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 consensus behind this document is pretty weak as this document was
held back until the softwire stateless transition solutions went
through the publication process. The document represents strong
concurrence of a few individuals with nobody opposed.

(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

No nits found.

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

The document has been reviewed by MIB doctors.

(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?


(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).

The document requires two IANA actions. It requires an assignment
under the SMI Numbers registry and it registers a new tunnel type.

(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.

I ran the libsmi checker on the document. It threw up two errors and
two warnings.

The two errors that come up are

mibs/SOFTWIRE-MESH-MIB:56: [2] {object-identifier-not-prefix} Object
identifier element `xxx' name only allowed as first element

mibs/SOFTWIRE-MESH-MIB:18: [2] {module-identity-registration} illegal
module identity registration

These will get fixed once IANA allocates the value xxx. I did put in
an available number to check and these errors went away.

The two warnings were also produced. Not sure what is causing these. A
look at the swmEncapsEntry and swmBGPNeighborEntry does not show any
obvious issues.

mibs/SOFTWIRE-MESH-MIB:110: [5] {index-exceeds-too-large} warning:
index of row `swmEncapsEntry' can exceed OID size limit by 136

mibs/SOFTWIRE-MESH-MIB:198: [5] {index-exceeds-too-large} warning:
index of row `swmBGPNeighborEntry' can exceed OID size limit by 135