Abstract: RSA algorithm is applied widely because of its security and usability, but the contradiction between the length of key and operating speed become an obstacle to the algorithm’s further development. This article analyzes and studies the traditional RSA algorithm, and according to the defects on speed, it puts forward an improved N-tuple RSA algorithm. The experimental results show that the improved algorithm is of higher efficiency and has certain value of application and popularization.

Key words: encryption, RSA algorithm, N-tuple RSA algorithm