Towards Practical Identification of HF RFID Devices

Abstract

The deployment of RFID poses a number of security and privacy threats such as cloning, unauthorized tracking, etc. Although the literature contains many investigations of these issues on the logical level, few works have explored the security implications of the physical communication layer. Recently, related studies have shown the feasibility of identifying RFID-enabled devices based on physical-layer fingerprints. In this work, we leverage on these findings and demonstrate that physical-layer identification of HF RFID devices is also practical, that is, can achieve high accuracy and stability. We propose an improved hardware setup and enhanced techniques for fingerprint extraction and matching. Our new system enables device identification with an Equal Error Rate as low as 0.005 (0.5%) on a set 50 HF RFID smart cards of the same manufacturer and type. We further investigate the fingerprint stability over an extended period of time and across different acquisition setups. In the latter case, we propose a solution based on channel equalization that preserves the fingerprint quality across setups. Our results strengthen the practical use of physical-layer identification of RFID devices in product and document anti-counterfeiting solutions.