Method and device for countering fingerprint forgery attacks in a communication system

摘要

A method and a fingerprinting device (400) for countering fingerprint forgery in a communication system (100; 200). The fingerprinting device (400) obtains and stores (310) a reference fingerprint for a client device (120), generates and transmits (320) decoy traffic (141 B) that appears to originate from the client device (120), the decoy traffic having different fingerprinting properties than real traffic from the client device (210), generates (330) a fingerprint for non-decoy traffic (141A; 141C) purportedly from the client device (210), and compares (340) the generated fingerprint with a reference fingerprint. A forged fingerprint is detected if there is a mismatch. The decoy traffic (141 B) preferably comprises frames to which no response is needed. The invention is particularly suited for 802.11 using fingerprints based on duration fields of received frames and the decoy traffic is then preferably probe request frames and null data frames.