PGP for VoIP

Philip Zimmermann is in hot water again. The author of the PGP encryption program has just released Zfone, which encrypts voice-over-IP phone calls. This is sure to prompt debate about the use of encryption for personal and business communication.

Unlike PGP, Zfone does not require exchanging public keys. It exchanges keys inside the voice channel as the call is being set up. Zfone does not work with Skype, one of the most popular VoIP programs, which uses its own encryption scheme. But the NYT reports that Skype’s encryption has been broken by the German government.

At a conference last week in Cyprus, German officials said they had technology for intercepting and decrypting Skype phone calls, according to Anthony M. Rutkowski, vice president for regulatory affairs and standards for VeriSign.