Enhanced 16x16 playfair techniques for secure key exchange using RSA algorithm
Pawan Tiwari, Dr. Sunil Gupta, Dr. Deepak Choudhary
In the time of internet when we are sending and receiving the information over the network in the presence of the third party then it is very necessary to protect our data from the attacker’s, in the series to protect the data we are using the cryptography algorithms. According to the key the encryption algorithm are of two types. First is symmetric key algorithm and second is asymmetric key algorithms. The proposed work is an example of the symmetric key with asymmetric key together. In the work I done the improvement in the play fair matrix technique. I used the all the rules of the basic play fair algorithm with some changes (changes in matrix).. The objective of this work is to securing the key of extended play fair technique of size16x16 using RSA algorithm (which is an Asymmetric key algorithm). It is a two stage algorithm. In the first stage existing methods of playfair cipher modified by increasing in the size of matrix, so that restrictions of earlier works of playfair (PF) cipher using 5×5 matrix were overcome in the proposed work. In this proposed method use a 16×16 matrix which contains all the alphabetic, numeric and special character use in the keyboard as input. This work is an enhancement to existing algorithms that uses 5×5 matrix to pick cipher characters. It makes use of alphabets both lower case and upper case characters, number and special characters for constructing the contents of the matrix and after this we use the rotation factor to rotate the matrix. In the second stage, the RSA public key encryption technique is used for sending key of the playfair ciphers securely and by this key we make the playfair matrix at the receiver end and we use the rotation factor to rotate the matrix after fill the key. By this matrix we can decrypt the cipher text and get the plain text finally, the security strength of the whole system has been analyzed and tried to fulfill requirement of security. At the last, thesis presents the scope for further work and concludes the thesis.