FMS-AMS: Secure Proximity-based Authentication for Wireless Access in Internet of Things

Jeongyoon Heo, Yongjae Yoo, Jihwan Suh, Woojin Park, Jeongyeup Paek, and Saewoong Bahk



Abstract :Proximity-based authentication enables wireless accesspoints (AP) to allow connection only to devices within a certain authenticationrange. This would be very convenient for allowing networkaccess only to those within a physical boundary. However, anattacker not within the authentication range may deceive the APinto authenticating its proximity by eavesdropping with higher receivergain and increasing its transmit power. This can be doneeasily using an amplifier or a directional antenna. To address thischallenge, we propose ‘Fixed MCS SNR (FMS)’ filtering schemebased on the intuition that high MCS requires high SNR, and amplifyingthe received signal strength does not necessarily improveSNR. We experimentally show that this is true in reality, and ourreal-world evaluation in various environments (14 locations) showsthat FMS scheme prevents ‘amplifier attacks’ in all cases. To furthercounter the false positives of FMS against ‘directional antennaattacks’ (avg. 35.7%), we also propose ‘Authentication Motionwith Signal strength gap (AMS)’ filtering scheme which defendsagainst both attacks in all cases at the cost of requiring the user tomake a simple motion. FMS or AMS scheme can be selected accordingto the application requirement to enhance the security ofproximity-based authentication in upcoming IoT​ 

Index terms :IEEE 802.11n, proximity-based authentication, security, wireless, authentication