Our GSM encryption software is designed to encrypt your mobile phone calls on the fly, protecting you from eavesdropping and call interceptions. Secure Voice GSM is a full duplex real time voice encryption solution, which allows you to talk and listen at the same time. The software is compatible with many Nokia handsets. No hardware modifications required! Call authentication is made using an unbreakable RSA encryption based on 1024 bit asymmetric key algorithm using a random key. The voice encryption is based on ultra strong ARC4 algorithm and made using the RSA start session key. Your calls can never be violated by any third party and that is guaranteed! Our software successfully passed highly advanced security tests performed by government experts and received a security certificate of Israeli Ministry of Defense. Secure Voice GSM is fully compatible with the following Nokia mobile phones: N70, N71, N72, N73, N73 Music Edition, N75, N76, N77, N93, N93i, N80, N90, N91, N91 8GB, E70, E61, E62, E60, E50, 6630, 6680, 6681.