The ZRTP Internet Draft

ZRTP: Media Path Key Agreement for Secure RTP

A proposal for a public standard

Phil Zimmermann, Alan Johnston, and Jon Callas have submitted an Internet Draft to the IETF for the ZRTP protocol, which is used by Zfone to set up the cryptographic key agreement. Alan co-authored RFC 3261 which defines the SIP standard, and Jon is CTO at PGP Corp.

Here's what we last submitted to the IETF

The ZRTP Internet Draft as last submitted on the IETF web site:

http://tools.ietf.org/html/draft-zimmermann-avt-zrtp
This link also contains older obsolete drafts that can be individually selected at the top of the page, and colorful tools to review the changes between drafts.

On our own web site, the submitted draft is also available:

HTML - Nicely formatted and easier to read than the format used on the IETF web site.

SDK for developers to implement the ZRTP protocol

We also have a software development kit to help you implement ZRTP in your VoIP application. Click here to see the Zfone libZRTP SDK documentation.

Ethereal (Wireshark) ZRTP packet dissector

If you are developing VoIP applications that use the ZRTP protocol, you may want to use the popular open source Wireshark protocol analyzer (formerly known as Ethereal) to inspect ZRTP packets. To make Wireshark recognize and dissect ZRTP packets, check out our nifty ZRTP packet dissector patch for Wireshark.