A Modified Feistel Cipher involving a key as a multiplicant on both the sides of the Plaintext matrix and supplemented with Mixing Permutation and XOR Operation

In this paper, we have developed a block cipher by offering a modification to the classical Feistel cipher. Unlike in the case of the classical Feistel cipher wherein we have a binary string as a plaintext, here we have taken the plaintext as a matrix, which is divided into a pair of matrices. One of these matrices is multiplied with the key matrix on both the sides. The process of encryption is supplemented with a pair of functions called Mix ( ) and Permute ( ). In addition to these two, we have used XOR operation. The avalanche effect and the cryptanalysis indicate that cipher is a strong one.