Using El Gamal Cryptosystem in Message Feedback Mode for Computing Cost Reduction

This paper discuses comparatively more efficient and cost effective scheme of El Gamal Cryptosystem by introducing the concept of using the established cryptosystems into message feedback mode. The idea behind this is, “an established cryptographic scheme can be used to initiate any communication, and further users may switch to some lightweight process so that the degree of secrecy is maintained by means of the public key cryptosystem and the performance is achieved by using some other lightweight process. Approach discussed in this paper is of using message itself as One Time Pad (OTP), because any automation can‟t produce any random pad than a human being, and their messages posses same property. The length of Key used in El Gamal encryption and size of OTP determines the level of secrecy offered by the proposed system. Further a discussion is made upon the other dimensions of degree of security provided in such implementation. So as a result an applied approach is presented to design a data security mechanism for which users will use message itself as a One Time Pad and El Gamal Cryptosystem to initiate the operations and subsequent steps will involve simple XOR operations for cryptographic purpose. General Terms Cryptography, Network Security, Public Key Cryptosystem, El-Gamal Algorithm