Transport Layer Security (TLS) Cached Information Extension
draft-ietf-tls-cached-info-23

[Ballot comment]
Just a quick comment, sorry for asking this late and I won't hold up on it either, just want to raise the question without quite enough time to research it all.

I see the SHA-256 truncation is just 32 bits.  In other applications, about half is what is typically recommended.  I know you are trying to cut on space, but will problems arise from this shorter value?

[Ballot comment]
-section 4, paragraph 4:
It might be helpful to have a little more guidance to clients for multi-tenant server environments. For example, the fact that it might want to cache different certs from the same server in the first place. Also, when might it be reasonable to violate the RECOMMENDED?

- 4.1:
Should the reference for 7250 be normative?

[Ballot comment]
I have two comments about Section 8.2:

1. The Standards Action range starts at 0, and you've assigned 1 and 2, but not 0.  Is it intended that 0 should remain reserved and unassigned?  If so, you should say that.

2. For the Specification Required range, is there any guidance you can/should give to the designated expert?  What do you expect the DE to look for when evaluating requests?  Why might the DE not approve a request?

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

IANA has completed its review of draft-ietf-tls-cached-info-20.txt. If any part of this review is inaccurate, please let us know.

IANA has a question about one of the actions requested in the IANA Considerations section of this document.

IANA understands that, upon approval of this document, there are two actions which IANA must complete.

First, in the ExtensionType Values subregistry of the Transport Layer Security (TLS) Extensions registry located at:

http://www.iana.org/assignments/tls-extensiontype-values/

a single new value will be registered as follows:

Value: [ TBD-at-registration ]
Extension name: cached_info
Reference: [ RFC-to-be ]

Second, a new registry is to be created called the TLS CachedInformationType values registry.

IANA QUESTION -> Where should this new registry be located? Is it a néw registry on the IANA Matrix or is it a subregistry of an existing registry? If it is a subregistry of an existing registry, in which registry will it be contained?

IANA understands that the registry maintenance rules for the new registry are as follows:

0-63 (decimal): Standards Action
64-223 (decimal): Specification Required
224-255 (decimal): reserved for Private Use

There are initial registrations in the new registry as follows:

Value: 1
Information Type: cert
Reference: [ RFC-to-be ]

Value: 2
Information Type: cert_req
Reference: [ RFC-to-be ]

IANA understands that these two actions are the only ones required to be completed upon approval of this document.

IANA will not be able to complete the registry actions for this document until these issues have been resolved.

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 Specialist
ICANN

The following Last Call announcement was sent out:

From: The IESG
To: "IETF-Announce"
CC: draft-ietf-tls-cached-info@ietf.org, joe@salowey.net, tls-chairs@ietf.org, tls@ietf.org, stephen.farrell@cs.tcd.ie
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (Transport Layer Security (TLS) Cached Information Extension) to Proposed Standard


The IESG has received a request from the Transport Layer Security WG
(tls) to consider the following document:
- 'Transport Layer Security (TLS) Cached Information Extension'
  as Proposed Standard

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 2015-12-04. 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


  Transport Layer Security (TLS) handshakes often include fairly static
  information, such as the server certificate and a list of trusted
  certification authorities (CAs).  This information can be of
  considerable size, particularly if the server certificate is bundled
  with a complete certificate chain (i.e., the certificates of
  intermediate CAs up to the root CA).

  This document defines an extension that allows a TLS client to inform
  a server of cached information, allowing the server to omit already
  available information.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-tls-cached-info/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-tls-cached-info/ballot/


No IPR declarations have been submitted directly on this I-D.

RFC 4634 has been obsoleted by RFC 6234. We'll fix the reference
later.

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?

This document is requested in standards track.  The extension defined in the document is of general use.  The document is identified as 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 defines an extension that allows a TLS client to inform
  a server of cached information, allowing the server to omit already
  available information.


Working Group Summary

This document has gone through a long working group process and many revisions.  We believe the document has had sufficient review and is ready for publication.  The TLS working group consensus around the document is not strong, as the main body of interest for this work is in the DICE group. 

Document Quality

This document has had extensive review over a long period of time in the TLS working group.  The document is a dependency of the DICE working group.

Personnel

Joseph Salowey is the document shepherd.  The responsible AD is Stephen Farrell.

(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 document shepherd has reviewed the document and believe 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?

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.

The document is about a security protocol.  The TLS working group has reviewed it for security.  In particular the way hashing of objects is done has been reviewed by the working group. 

(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 particular 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.

No IPR is known or has been disclosed.

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

No declaration has been filed.

(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? 

Much of the working group is not deeply interested in the document, however it has received significant review from key members of the working group.  There is consensus to move the document forward. 

(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.

NA

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

NA

(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?

NA

(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

(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.

It does not change 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).

New registries are defined and named appropriately

(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.

Part of the "CachedInformationType" registry has the specification required policy.  The guidance for this review:

- document does not define a cached-info type that already exists. 
- document is well defined specification that allows for interoperability that is compatible with the usage of the extensions defined in this document
- document provides guidance for an security considerations introduced by the new type


(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.

NA