An Enhanced Polyalphabetic Cipher using Extended Vigenere Table

Abstract

The objective of this investigation is to find the competent and most extensively used cryptographic algorithms form the history,
identifying one of its merits and demerits which have not been modified so far. A proposal will be given to overcome the problems in the
investigated algorithms to meet the current requirements. Observation of cryptography, its techniques such as transposition & substitution were
discussed. Our main focus is on the Poly alphabetic Cipher, its advantages and disadvantages. Finally we have proposed a method to enhance the
Poly alphabetic cipher for more secure and efficient cryptography.

Keywords: Security; Algorithm; Cipher;Cryptography;Encryption;Decryption;Substitution;Transposition;Vigenere Table;