Date Added: Feb 2011
The essential aspect of secured communications is secret key cryptography. The key selection mechanism and the encoding methodology determine the efficiency of the cipher text generated. In this paper, RSU algorithm is proposed which encodes the message by using reversible Boolean functions and combinatorics. In this method, same keys are used for both encryption and decryption. The plaintext and secret keys are modified before encryption. This increases the complexity of deciphering the cipher text by intruders. Thereby it provides extremely better security for data.