A Modified Feistel Cipher Involving a Key as a Multiplicant on Both the Sides of the Plaintext Matrix and Supplemented with Mixing, Permutation, and Modular Arithmetic Addition

In this investigation, we have generalized the classical Feistel cipher by representing the plaintext in the form of a matrix instead of a binary string used in the case of classical Feistel cipher. In this, the plaintext matrix is divided into two matrices and one of these two is multiplied with the key matrix on both the sides. In the iteration process, involved in this cipher, we have included a pair of functions namely Mix ( ) and Permute ( ), and also utilized modular arithmetic addition. All these features are expected to strengthen the cipher. The avalanche effect and the cryptanalysis clearly show that the cipher is a potential one.