A modern avatar of Julius Ceasar and Vigenere cipher

Julius Caesar and Vigenere ciphers are ancient methods of determining the cipher text for any given plain text message, They are very elementary and simple methods. But with the advent of powerful computers these methods weaken against the onslaught of cryptanalysis. Therefore by using the rigorous mathematical tools this paper proposes to rejuvenate Julius Caesar and Vigenere ciphers to make them difficult to decrypt. It involves a prime factor, its primitive roots and their generator. The basic philosophy of Julius Caesar and Vigenere are preserved, but the shifts and substitutions are non-uniform following a scientific procedure. This make cryptanalysis of the proposed algorithm a very difficult task.