Physically Unclonable Function-Based Security and Privacy in RFID Systems

Abstract

Radio Frequency Identification (RFID) is an increasingly popular technology that uses radio signals for object identifi- cation. Tracking and authentication in RFID tags have raised many privacy and security concerns. On the other hand, known privacy and security cryptographic defenses are too hardware- expensive to incorporate into low-cost RFID tags. In this paper, we propose hardware-based approaches to RFID security that rely on physically unclonable functions (PUFs). These func- tions exploit the inherent variability of wire delays and par- asitic gate delays in manufactured circuits, and may be im- plemented with an order-of-magnitude reduction in gate count as compared with traditional cryptographic functions. We de- scribe protocols for privacy-preserving tag identification and secure message authentication codes. We compare PUFs to digital cryptographic functions, address other uses of PUFs to enhance RFID security and suggest interesting directions for future research. The proposed solutions are efficient, practical, and appropriate for low-cost RFID systems.