[Fwd: I-D ACTION:draft-zimmermann-avt-zrtp-02.txt]

[Alan Johnston <alan@xxxxxxxxxxxxxx>]

All,

The ZRTP I-D has been updated.  There are lots of changes in the 
document including:


- Discussion of how ZRTP compares using the criteria in 
draft-wing-rtpsec-keying-eval-01.txt

- Discovery and authentication of ZRTP through the signaling channel and 
the definitions and ABNF of three SDP attributes a=zrtp, a=zrtp-sas, 
a=zrtp-sasvalue.

- New Multistream key agreement mode allowing SRTP keys for multiple 
media streams in a session to be derived from a single  ZRTP DH exchange.

- CRC protection of ZRTP messages against transport errors using a 32 
bit CRC algorithm

- Use of RTP no-op packets instead of comfort noise packets

- Simplified shared secret comparison algorithm

- New Stay secure and Disclosure flags

- More details on caching of retained shared secrets including 
expiration intervals

- Removal of Error message - Reason field added to GoClear

- Discussion of the behavior of intermediary devices that might 
implement ZRTP


We will be discussing the changes in the ZRTP protocol in the AVT 
working group and the SDP attributes in MMUSIC.

As always, comments and feedback are most welcome.

Thanks,
Alan

-------- Original Message --------
Subject: 	I-D ACTION:draft-zimmermann-avt-zrtp-02.txt
Date: 	Tue, 24 Oct 2006 15:50:02 -0400
From: 	Internet-Drafts@xxxxxxxx
Reply-To: 	internet-drafts@xxxxxxxx
To: 	i-d-announce@xxxxxxxx



A New Internet-Draft is available from the on-line Internet-Drafts 
directories.


	Title		: ZRTP: Extensions to RTP for Diffie-Hellman Key Agreement for SRTP
	Author(s)	: P. Zimmermann, et al.
	Filename	: draft-zimmermann-avt-zrtp-02.txt
	Pages		: 52
	Date		: 2006-10-24
	
This document defines ZRTP, RTP (Real-time Transport Protocol) header
  extensions for a Diffie-Hellman exchange to agree on a session key
  and parameters for establishing Secure RTP (SRTP) sessions.  The ZRTP
  protocol is completely self-contained in RTP and does not require
  support in the signaling protocol or assume a Public Key
  Infrastructure (PKI) infrastructure.  For the media session, ZRTP
  provides confidentiality, protection against Man in the Middle (MitM)
  attacks, and, in cases where a secret is available from the signaling
  protocol, authentication.  ZRTP can utilize three Session Description
  Protocol (SDP) attributes to provide discovery and authentication
  through the signaling channel.

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