DefinePK

Abstract

In modern cryptography, the P-Boxes and S-boxes are used to make the relation between the plaintext and the cipher text difficult to realize. P-Box is a tool that changes the order of the input bits and they appear in the output. In this case, the key is order transmission of input bits in output bits. An S-box is a basic component which performs substitution. In this paper, a new method for the production of P-Box with the help of modular computing is introduced in a way that the order of the input bit transfer in output is the function of the encryption key. Next, development of this algorithm is used to make S-box structure. And also if the current symmetric encryption methods used, the P-Box and S-Box keys are derived from the key encryption method. In general, there is no need to increase the length of current key to use the P-Box and S-Box recommended.