El gamal encryption using lucas, Elliptic curve and SRZ model

Abstract

In cryptography, the security is depending on the way in which it produces different ciphertexts for the same plaintext so that the eavesdropper is not able to recover the plaintext from the ciphertext. Though, several block cipher modes viz., CBC, CFB and OFB exist, they take more time for producing different ciphertext blocks for the same plaintext block. To avoid this, an encoding is performed at the plaintext level. There are several encoding schemes like ASCII, Magic Square, and Magic Rectangle based encoding exist in the literature. But, in this paper, a novel encoding technique based on Elliptic Curve, Lucas number, Spiral Clockwise Rotation and Zigzag transformations called ECLUSRZ has been proposed. As, the original form of plaintext is completely altered using this proposed encoding scheme, the eavesdropper may not easily recover the plaintext from the ciphertext. Once, the encoding is performed, the encoded numeral called intermediate plaintext is then used for any one of the public key cryptosystems like ElGamal and the security level produced by ElGamal encryption with ASCII based and the proposed ECLUSRZ based encoding is analyzed.