Involutory, Permuted and Reiterative Key Matrix Generation Methods for Hill Cipher System
Bibhudendra Acharya, Sarat Kumar Patra, Ganapati Panda · 2009
Abstract—The Hill matrix algorithm is known for being the first purely algebraic cryptographic system and for starting the entire field of algebraic cryptology. Hill cipher's susceptibility to cryptanalysis has rendered it unusable in practice; it still serves an important pedagogical role in both cryptology and linear algebra. Hill cipher requires inverse of the key matrix while decryption. In fact that not all the matrices have an inverse and therefore they will not be eligible as key matrices in the Hill cipher scheme. Furthermore, due to its linear nature, the basic Hill cipher succumbs to known-plaintext attacks. In order to repair these flaws of the original Hill cipher, in this paper we proposed Involutory, Permuted and Reiterative key matrix generation method for Hill Cipher system. Involutory matrix generation method solves the key matrix inversion problem. Permuted and Reiterative key matrix generation method enhancement increases the Hill system's security considerably