Model Checking of RADIUS Protocol in Wireless Networks

Authentication server based security protocols are mainly used for enhancing security of wireless networks. In this paper, we specify RADIUS security protocol in wireless networks with Casper and CSP, and then verify their security properties such as secrecy and authentication using FDR. We also show that RADIUS protocol is vulnerable to the man-in-the-middle attack. In addition, we discuss its security weakness and potential countermeasures related with RADIUS. Finally, we fix it and propose a modified RADIUS protocol against the man-in-the-middle attack.