NSA develops secure Android phones

The US National Security Agency has developed and published details of an encrypted VoIP communications system using commercial off-the-shelf components and an Android operating system.

A hundred US government employees participated in a pilot of Motorola hardware running hardened VoIP (PDF) called 'Project Fishbowl', NSA Information Assurance Directorate technical director Margaret Salter told the RSA Conference in San Francisco on Wednesday.

"The beauty of our strategy is that we looked at all of the components, and took stuff out of the operating system we didn't need," said Salter. "This makes the attack surface very small."

The open-source nature of Android gave the NSA the 'freedom' to develop in a way that wasn't possible with Apple's proprietary iOS operating system, said Salter.

The NSA encrypted the VoIP communication, and used encrypted VPN tunnelling as a second security layer. The handsets were password protected, and authenticated to other handsets using certificates.

Calls using the handsets did have "a little bit of delay" said Salter. The US Defence Information Systems Agency, which is part of the Department of Defence, may now test the architecture.