关键词: 密码学, 认证, 协议, 椭圆曲线离散对数问题, 智能卡, 口令

Abstract:  A smart card based remote user authentication scheme is more secure than a password-based authentication scheme. In 2011, Chen et al. proposed an improvement on Hsiang et al. ’s remote user authentication scheme, and claimed their scheme was more secure than Hsiang et al. ’s scheme. However, their scheme is still vulnerable to insider attack, lost smart card attack, replay attack, and impersonation attack. To overcome the dictionary attack against lost smart card, a user authentication scheme based on smart card and elliptic curve discrete logarithm problem is proposed. This scheme is proved to be secure agaisnt various attacks and needs only one elliptic curve scale multiplication in the login and authentication phases.

Key words: cryptography, authentication, protocol, Elliptic Curve Discrete Logarithm Problem（ECDLP）, smart card, password