Determining the Secrecy of Software Encryption System based on pGSSG Generator using Shannon Entropy

This paper focuses on the application of previously proposed p-ary Generalized Self-Shrinking Generator (pGSSG). Software encryption system using keystream produced by the pGSSG is developed and analyzed. For initialization of the generator Galois Field GF(25732) and feedback polynomials are chosen. A mathematical model of the software encryption system is made. It is proved that it is not perfect but the empirical tests with calculation of entropy for input and encrypted files show that it has less than 0.0125% deviation from the perfect secrecy.