Wireless Lan Security Mechanism

As its flexibility and convenience, Wireless Local Area Network (WLAN) is widelyused in corporations, offices, airports, hospitals, and at home, or in special environment fordealing with an emergency event. However, opening wireless transmission brings somesecurity vulnerabilities into WLAN, such as data is easily eavesdropped, intercepted andmodified, as well as Denial of Sevices and masquerading attacks are easily mounted.In order to solve these security problems, upon analyzing the network features andsecurity need of WLAN, vulnerabilities are summarized and classified. In the latestinfrastructures of two main standards-IEEE 802.11i and WAPI, the infrastructures ofWAPI is analyzed mainly which is self-owned intellectual property rights in our country,and vulnerabilities and shortcomings in WAPI are pointed out, which include inefficientauthentication, sources-costly computation and DoS attacks brought up with the design ofprotocols, which influence the availability of WLAN. In WAPI, the STA is not authenticatedby AS and the key negotiation protocol is incomplete. Furthermore, DOS attacks are easilyamounted in the standard. In order to solve these problems, some improved schemes andmethod are proposed that could improve the security, availability and computationefficiency of WAPI. Authentication server (AS) system is designed and accomplished withthe introduction of multiple-threads and multiple-cache techniques. It has been verified thatthe designed AS system is effective and available through experiment and emulation.The Authentication Service Unit (ASU) in WAPI is kernel and elements, and itsprimary function is to implement the management of user certificate and the identificationof user identity. The WAI relies on the public key infrastructure——PKI service providedby ASU. In this paper the authentication service system of WAPI is designed andimplemented by using the technology of multi-thread and multi-buffer. The validity andusability of this system are proved by experimenting and simulating.