Abstract
Due to its convenience and simplicity, the mobile application in the mobile devices has been widely used as necessary. As an essential way to provide secured communication between mobile users and servers, the authentication protocol for user devices has stirred active study. However, because mobile devices are limited on computing capability and energy, it still remains a difficult problem for designing a secure and efficient authentication and key agreement protocol for mobile devices. In this paper, we propose a new efficient and secure Identity-based authentication and key agreement protocol using elliptic curve cryptosystem for mobile devices. Security analysis and complexity comparisons show our proposed protocol can fulfill all of security requirements while has lower computation and communication costs than similar protocols for mobile devices.