A Simple Algebraic Model Based Polyalphabetic Substitution Cipher
Cryptography is considered to be a disciple of science of achieving security by converting sensitive information to an un-interpretable form such that it cannot be interpreted by anyone except the transmitter and intended recipient. An innumerable set of cryptographic schemes persist in which each of it has its own affirmative and feeble characteristics. In this paper, the authors have developed a traditional or character oriented Polyalphabetic cipher by using a simple algebraic equation. This key strengthens the cipher and it does not allow the cipher to be broken by the known plain text attack. The cryptanalysis performed clearly indicates that the cipher is a strong one..