Enables the encryption of the voice communication through the mobile phone in the gsm network. Aes algorithm with a 256-bit key for voice encryption. Alternatively proprietary algorithm or other user defined encryption algorithm. One-time encryption keys - there are always new keys created with every new phone call. The key used with the current phone call will automatically be destroyed after the completion of the communication. The diffie-hellman algorithm provides an exchange of the one-time keys. The rsa algorithm authenticates the phone call. Can be used in any gsm network 900/1800/1900 mhz which supports the data call (csd). Supports roaming - the call encryption works also abroad depending on the operator. The voice quality is the same as with the regular phone call - amr voice compression. The contact list is stored in an encrypted form in the mobile phone. You can choose a mobile phone from the list of symbian compatible mobile phones. All mobile phone functions are accessible without any restrictions. User communicates via headset (any standard). Connection with the mobile phone is via bluetooth. Bluetooth connection is additionally encrypted with aes 256 (over original bluetooth encryption). Authentication. The key management.