In this paper, we propose a secure and efficient user authentication scheme with countable and time-bound features. The countable feature is to limit the use to a certain number of times, which means that the users are able to successfully log into the system in a fixed number of times. The feature of the time-bound allows each login ticket to have a period of expiration. In other words, if a login request is overdue, it would not be available anymore. These features make our scheme more reliable for applications in the field of electronic commerce, such as on-line games, pay-TV, and so on. Since our scheme does not require any password or verification table and can avoid replay attacks, it is under firm security. Moreover, our scheme shows a lower computational overhead on the user side. Therefore, it offers an efficient and adequate alternative for the implementations in the mobile environment with limited computing capability.
['Iuon-Chang Lin', 'Chin-Chen Chang']
A countable and time-bound password-based user authentication scheme for the applications of electronic commerce