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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