On Wireless Rogue Access Detection Using Clock Skew Method

Rogue Access Point (RAP) is an access point that has been installed on a secure network without explicit authorization from a system administrator. The major security thread for the Wireless Networks is a presence of Rough access points. If this kind of network threats are not detected and mitigated on time, those will lead to the serious network damage and data loss. Finding and avoiding rogue wireless access points is a main issued for every organization. We use clock skew as a parameter of a wireless access point (AP) to detect unauthorized AP's. Using clock skews method to detect Rogue access point in wireless LAN network overcomes the limitations of existing solutions. We calculate the clock skew of an AP from the IEEE 802.11 Time Synchronization Function (TSF) time stamps sent out in the beacon/probe response frames. We use leastsquare fit method for this purpose. Our results indicate that the use of clock skews appears to be an effective and robust method for detecting fake AP's in wireless local area networks.