Secure and Efficient Two-Factor Authentication Protocol Using RSA Signature for Multi-server Environments

To avoid multiple number of registrations using multiple passwords and smart-cards, many two-factor multi-server authentication protocols based on RSA have been proposed. However, most of the existing RSA-based multi-server authentication protocols are susceptible to various security attacks, and have high computation complexities. Recently, Amin et al. proposed a two-factor RSA-based robust authentication system for multi-server environments. However, we found that Amin et al.'s protocol cannot resist common modulus attack. To enhance the security, we propose a secure two-factor RSA-based authentication protocol for multi-server environments. The performance and security features of our scheme are also compared with that of the similar existing schemes. The performance and security analysis show that our protocol achieves more security features and has lower computation complexity in comparison with the latest related schemes.