A Block Cipher using Feistal's Approach Involving Permutation and Mixing of the Plaintext and the Additive Inverse of Key Matrix

Abstract

In this research, we have developed a block cipher for a block of size 112 bits by using an iterative method involving a permutation of the plaintext and the subkeys generated in each iteration. Here we have represented the plaintext as a matrix of f size 14×8, comprising binary bits. In the process of encryption, we have used a key matrix (K), which also consists of binary bits and generated subkeys from K for each iteration. For decryption, we have used the Additive inverse (K'i)⁻¹ of the subkeys. In this, we have discussed the cryptanalysis and have shown that the cipher cannot be broken by any cryptanalytic attack.