An efficient decryption method for RSA cryptosystem

• Published in: 19th International Conference on Advanced Information Networking and Applications (AINA'05) Volume 1 (AINA papers) Vol. 1; pp. 585 - 590 vol.1
• Main Authors: Ren-Junn Hwang, Feng-Fu Su, Yi-Shiung Yeh, Chia-Yao Chen
• Format: Conference Proceeding
• Language: English
• Published: IEEE 2005
• Subjects: Application software; Cathode ray tubes; Computational efficiency; Computer science; Electronic commerce; Information security; National security; Protocols; Public key; Public key cryptography
• ISBN: 9780769522494; 0769522491
• ISSN: 1550-445X; 2332-5658
• DOI: 10.1109/AINA.2005.97

This paper proposes an efficient method to implement RSA decryption algorithm. RSA cryptosystem is the most attractive and popular security technique for many applications, such as electronic commerce and secure Internet access. It has to perform modular exponentiation with large exponent and modulus for security consideration. The RSA cryptosystem takes great computational cost. In many RSA applications, user uses a small public key to speed up the encryption operation. However, the decryption operation has to take more computational cost to perform modular exponentiation by this case. This paper proposes an efficient decryption method not only based on Chinese remainder theorem (CRT) but also the strong prime of RSA criterion. The proposed decryption method only takes 10% computational costs of the traditional decryption method. It also reduces 66% computational costs than that of decryption methods based on CRT only. In a word, the speed of our proposed method is almost 2.9 times faster than the decryption method based on CRT only. The proposed method enhances the performance of the RSA decryption operation.