Communication equipment, communications system and method therefor

The invention provides a communication device, a communication system for extended authentication part encryption scheme based on two dispute arbitration modes and a method. In the format of the single receiver, a sender can send the partial encrypted message to the receiver and only the receiver can decrypt and verify the message. The secret rescission mode or secret keeping mode can be set so as to determine whether to expose the secret message in the dispute arbitration. In the format of multiple receivers, a security forwarding center is used for forwarding the message received from the sender to multiple receivers, and the sender only needs to encrypt and sign single sent message. The message consists of different messages corresponding to different receivers. The security forwardingcenter decrypts and verifies the message received from the sender and forwards the message to each specified receiver according to the forwarding strategy.