FreeSWITCH Now Supports ZRTP!

The development team is pleased to announce that preliminary support for ZRTP as been added to the Linux, Unix, and Mac OS X versions of FreeSWITCH. Windows support will be added shortly.
 
ZRTP is a key agreement protocol for establishing SRTP streams. ZRTP is not limited to a specific signaling protocol because the key exchange is done within the RTP stream, therefore ZRTP works with SIP and H.323. ZRTP is opportunistic: if ZRTP is available at both ends of a call then an SRTP connection is automatically negotiated, otherwise a standard RTP stream is used.
 
ZRTP is part of the Zfone project, designed by Philip Zimmermann, the orignal creator of PGP. It was designed with the goal of being a better architecture for protecting VoIP calls. ZRTP offers very good security with low CPU overhead.
 
To use ZRTP you will need to update to the latest version of FreeSWITCH from the SVN trunk. You will also need to download the Zfone libZRTP Software Development Kit. Complete instructions are available on the FreeSWITCH wiki.
 
Right now virtually any softphone can be used with ZRTP. The Zfone project has a plug-in that can be downloaded here. Many softphones have been tested, including x-lite, Gizmo, SJPhone, and others.