The Design And Implementation Of802.1X Authencation System Based On Centralized WLAN Architecture

With the advances in wireless communications technology, large-scale deployment ofWireless Local-Area Network has become possible. Traditional WLAN deployment requiresthe administrator to configure access points one by one, as the scale of network grows, its lowefficiency and error-prone defects revealed gradually. Therefore, scholars proposed acentralized WLAN architecture that uses "thin access point" access mode, all the management,configuration and other work was done by the access controller, which reduces deploymentand operational costs, while also provide a centralized management model for operator.In the centralized WLAN architecture, the access controller is the core of the network, itmanagements and controls a large number of thin access points and stations, its performanceis related to the quality of the entire network directly, so the design of access controller isparticularly critical. Access controller uses RadiSys ATCA-7220packet processing blade asits hardware platform, and adopts ICE to achieve the system’s message mechanisms.The article thorough analyses the structure of authentication and propose the protocolsystem of802.1X,software architecture,primary function process,four step handshake processand timer solution in centralized WLAN architecture.At last,we analyse the process bycollecting data packets.