On the Reliability of Wireless Fingerprinting Using Clock Skews
Determining whether a client station should trust an access point is a known problem in wireless security. Traditional approaches to solving this problem resort to cryptography. But cryptographic exchange protocols are complex and therefore induce potential vulnerabilities in themselves. The authors show that measurement of clock skews of access points in an 802.11 network can be useful in this regard, since it provides fingerprints of the devices. Such fingerprints can be used to establish the first point of trust for client stations wishing to connect to an access point.