The Use of Timed Efficient Stream Loss-Tolerant Authentication (TESLA) in the Secure Real-time Transport Protocol (SRTP)
draft-ietf-msec-srtp-tesla-05

Approval announcement
Draft of message to be sent after approval:

Announcement

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: Internet Architecture Board <iab@iab.org>,
    RFC Editor <rfc-editor@rfc-editor.org>, 
    msec mailing list <msec@ietf.org>, 
    msec chair <msec-chairs@tools.ietf.org>
Subject: Protocol Action: 'The Use of TESLA in SRTP' to Proposed 
         Standard 

The IESG has approved the following document:

- 'The Use of TESLA in SRTP '
   <draft-ietf-msec-srtp-tesla-06.txt> as a Proposed Standard

This document is the product of the Multicast Security Working Group. 

The IESG contact persons are Russ Housley and Tim Polk.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-msec-srtp-tesla-06.txt

Ballot Text

Technical Summary
 
  For broadcast or multicast use of SRTP, for instance in
  group conferencing, symmetric key based (group key based)
  message integrity is not sufficient.  For data origin
  authentication, some type of digital signature based
  technique is typically necessary. TESLA is a MAC-based data
  origin authentication algorithm that uses delayed key
  disclosure to amortize the cost of digital signatures, and
  can also work without using signatures.  This document
  specifies the use of TESLA with the SRTP protocol.
 
Working Group Summary
 
  Historically, there have been arguments in the MSEC WG
  (and in SMuG RG) around the TESLA loose time synchronization
  requirement.  The MSEC WG determined that this requirement was
  acceptable.  The loose time synchronization in TESLA comes with
  strict requirements on packet integrity verification.  In that
  context, there was a contentious discussion around whether to
  drop packets arriving too late (w.r.t. time synchronization
  requirement).  The discussion was around "MUST" vs. "MAY", and
  the WG finally settled on "SHOULD." 
 
Protocol Quality

  TESLA has generally received a fairly thorough review within
  the MSEC WG, and there is at least one implementation.  TESLA-SRTP
  has been reviewed thoroughly by the MSEC WG, and positive feedback
  was received after a review by the AVT WG.   There are no known
  implementations of TESLA-SRTP.

  This document was reviewed by Russ Housley for the IESG.

RFC Editor Note