Implementation of Information Security System with Proposed Substitution Cipher Model Using Cryptography Tools and Methods

This paper shows the possibility of exploiting the features of substitutions cipher with ASCII values of the given text and then applying conversion, transposition and shows some unreadable form. In substitution ciphers the plaintext letters are enciphered differently depending upon their placement in the text. As the name polyalphabetic suggests this is achieved by using several two, three keys and random keys combinations instead of just one, as is the case in most of the simpler crypto systems. Using two keys, we take 2 keys e1, e2 and let the ASCII values of e1 be 1 and e2 be 2 and take the text, add ASCII values of e1 to first character and ASCII values of e2 to second character. Alternatively add the value of e1 and e2 to consecutive characters. Here we introduced security layer that is user can select their security level based on their communication over Internet.