Design And Implementation Of A Web-based Authentication And Accounting System For Wireless LAN

This thesis focuses on the design and implementation of a Web-based Authentication and Accounting System, which provides Internet authentication service for small area hot spots. This system, offering a good detection of abnormal disconnection, can realize user authentication, accounting, management and other functionalities with good security, high reliability, good maintainability and user-friendly interface.Firstly, the thesis analyses and compares three popular authentication technologies: PPPoE authentication, 802. lx authentication and Web authentication. By considering the characteristic of wireless LAN, the Web authentication technology was chosen for the system because of its convenience for users to access the Internet. After completing the system design, the development environment under Linux System for WEB server module and background database is adopted. Then according to the author's laboratory conditions, the background database, user interface and system management tool were designed.To guarantee the security of user authentication, a double-check authentication strategy which uses both password and check code is presented. Meanwhile, a new method, using Servlet listener with Java timer, is proposed and implemented to detect users' abnormal disconnections.A web-based system management tool is also designed and implemented, which provides a series of operations for the system administrator, such as to add, delete, modify, list or search all the information of a user. Besides, to maintain the background database, a small program is made to delete out-of-date data automatically.Based on the completion of all the system modules, a method which uses the redirection and socket communication technology is given to complete system integration. Then an integration test result was presented. Finally some remarks and suggestions on further optimization of the authentication and accounting system were summarized, and possible solutions to the existing problems were put forward.