In-building intruder detection for WLAN access

In recent years wireless local area network (WLAN) has become a popular choice for local area networking in both enterprise and home networking. Increased data rate and price reduction in IEEE 802.11b-g devices has made WLANs even more attractive in these markets. User mobility has opened a new market for location aware, and pervasive computing applications. As a service to these new applications, security and user authentication plays a more important role in a wireless environment compared to the conventional wired systems. In the corporate WLAN environment, since a mobile wireless networks intruder can access the network without physical presence inside the buildings, the solutions for intruder detection has attracted considerable attention by the research community. In this paper we first provide an overview of the traditional location sensing and intruder detection algorithms that are using the existing IEEE 802.11 infrastructure. Then we introduce a new algorithm targeted for intruder detection and authentication in a WLAN network. The new algorithm uses indoor radio propagation modeling to reduce complexity of the calibration process used in the existing algorithms. The performance of the existing and the new algorithm in the first floor of the Atwater Kent Laboratory at the Worcester Polytechnic Institute is used as a basis to compare the performances.