Zfone, encrypted VoIP from the makers of PGP
an article by Carlo, author of SpaghettiTech, March 2006
Philip Zimmerman, well known amongst the security savvy users for the renowned encryption software PGP (Pretty Good Privacy), just released a public beta version (currently for Mac OS X and Linux: the XP version will be released in April) of Zfone, a VoIP software based on a new protocol called ZRTP, which has some nice cryptographic features lacking in many other approaches to VoIP encryption ...
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