Subject: [AVT] Document writeup for draft-ietf-avt-srtp-big-aes-05

From: "DRAGE, Keith (Keith)" <[email-masked]>
Date: Tue, 30 Nov 2010 01:04:15 +0100

I have just requested publication of draft-ietf-avt-srtp-big-aes-05 as proposed standard.

The document writeup follows this message

regards

Keith

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Shepherd writeup for draft-ietf-avt-srtp-big-aes-05 "The use of AES-192 
and AES-256 in Secure RTP" as proposed standard.

  (1.a) Who is the Document Shepherd for this document? Has the
        Document Shepherd personally reviewed this version of the 
        document and, in particular, does he or she believe this 
        version is ready for forwarding to the IESG for publication? 

The document shepherd for this document is Keith Drage.

The document shepherd has reviewed the document and believes it is ready for 
forwarding to the IESG for publication.

Document history:

-	draft-mcgrew-avt-srtp-big-aes-00 was submitted 26th April 2006 
and expired 28th October 2006;
-	draft-mcgrew-avt-srtp-big-aes-01 was submitted 5th March 2009 
and expired 6th September 2009;
[-	draft-ietf-avt-srtp-big-aes-00 was submitted 24th August 2006 
and expired 15th February 2007];
-	draft-ietf-avt-srtp-big-aes-01 was submitted 6th July 2009 and 
expired 7th February 2010;
-	draft-ietf-avt-srtp-big-aes-02 was submitted 25th October 2009 
and expired 28th April 2010;
-	draft-ietf-avt-srtp-big-aes-03 was submitted 8th March 2010 and 
expired 9th September 2010;
-	draft-ietf-avt-srtp-big-aes-04 was submitted 15th September 2010 
and expires 19th March 2011.
-	draft-ietf-avt-srtp-big-aes-05 was submitted 29th September 2010 
and expires 2nd June 2011.

Call for adoption of baseline as WG item was made 10th March 2009.

Working group last calls were held on the document as follows:
-	15th June 2010 to complete 29th June 2010 on -03 version as 
proposed standard. Reviews were received from Jonathan Lennox, Glen 
Zorn and Cullen Jennings.

Prior to WGLC the document was reviewed by John Mattsson

  (1.b) Has the document had adequate review both from key WG members 
        and from key non-WG members? Does the Document Shepherd have 
        any concerns about the depth or breadth of the reviews that 
        have been performed?  

The document has been adequately reviewed (see 1a above)

  (1.c) Does the Document Shepherd have concerns that the document 
        needs more review from a particular or broader perspective, 
        e.g., security, operational complexity, someone familiar with 
        AAA, internationalization or XML? 

The document has not yet had a full security directorate review.

  (1.d) Does the Document Shepherd have any specific concerns or 
        issues 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. Has an IPR disclosure related to this document 
        been filed? If so, please include a reference to the 
        disclosure and summarize the WG discussion and conclusion on 
        this issue. 

There are no concerns from the document shepherd perspective with the document.

The AD has asked questions concerning the use case for these extended values. 
This has been responded to on the mailing list, essentially identifying that 
while existing SRTP mechanisms are considered secure, many contracts are now 
calling for the availability of extended keys.

No IPR disclosures have been made against this document.

  (1.e) 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 interest in this document has been relatively small, but it has been well 
reviewed by experts (and implementation experience has been applied to the 
document as well). Note that the document itself contains few implementable 
requirements directly, but does need to be taken into account in implementing 
the extended keys.

  (1.f) 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 
        entered into the ID Tracker.) 

No appeals or areas of conflict or discontent have been identified.

  (1.g) Has the Document Shepherd personally verified that the 
        document satisfies all ID nits? (See the Internet-Drafts Checklist 
        and http://tools.ietf.org/tools/idnits/). Boilerplate checks are 
        not enough; this check needs to be thorough. Has the document 
        met all formal review criteria it needs to, such as the MIB 
        Doctor, media type and URI type reviews? 

Version 2.12.05 of ID nits identifies no issues.

As a security related document, documents of this scope would normally merit a 
security review before publication request. No such review has yet been 
performed, although it is believed the document is simple enough to not be 
contentious.

  (1.h) Has the document split its references into normative and 
        informative? 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 
        strategy for their completion? Are there normative references 
        that are downward references, as described in [RFC3967]? If 
        so, list these downward references to support the Area 
        Director in the Last Call procedure for them [RFC3967]. 

The document does split normative and informative references. All the normative 
references have been reviewed and are correctly allocated as normative 
references. None of these normative references constitute a down reference.

  (1.i) Has the Document Shepherd verified that the document IANA 
        consideration section exists and is consistent with the body 
        of the document? If the document specifies protocol 
        extensions, are reservations requested in appropriate IANA 
        registries? Are the IANA registries clearly identified? If 
        the document creates a new registry, does it define the 
        proposed initial contents of the registry and an allocation 
        procedure for future registrations? Does it suggest a 
        reasonable name for the new registry? See [RFC5226]. If the 
        document describes an Expert Review process has Shepherd 
        conferred with the Responsible Area Director so that the IESG 
        can appoint the needed Expert during the IESG Evaluation? 

An IANA considerations section is included and the 

  (1.j) Has the Document Shepherd verified that sections of the 
        document that are written in a formal language, such as XML 
        code, BNF rules, MIB definitions, etc., validate correctly in 
        an automated checker? 

The only formal language is contained in the test cases. 

The test cases were generated in a semi-automated way, using some hand- 
generated inputs and a command-line application that does AES and XOR 
operations.  Most importantly, these cases were checked by John 
Mattsson of Ericsson, who used completely independent software and a  
different, more automated methodology.

  (1.k) 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. 
     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? 
     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 describes the use of the Advanced Encryption Standard 
(AES) with 192 and 256 bit keys within the Secure RTP protocol.  It 
details Counter Mode encryption for SRTP and SRTCP and a new SRTP Key 
Derivation Function (KDF) for AES-192 and AES-256.

The document achieved consensus in the AVT working group.

David McGrew, Jonathan Lennox (in the the open-source libsrtp project) and 
Philip Zimmermann (in libZRTP) have indicated implementations of this 
internet-draft.