Modified Trail Division for Implementation of RSA Algorithm with Large Integers

The RSA cryptosystem, invented by Ron Rivest, Adi Shamir and Len Adleman was first published in the August 1978 issue of ACM. The cryptosystem is most commonly used for providing priva cy and ensuring authenticity of digital data. The security level of this algorithm depends on chooing two large prime numbers. But, to handle large prime in personal computer is huge time consuming. Further, each and every compiler has a maximum limit to integer handling capability. In this paper, an approach has been made to modify trial division technique for implementation of RSA algorithm for large numbers beyond the range of a compiler that has been used to implement it. The time complexity of this modified trial division method has been calculated using personal computer, at the end for large integer.