On the Use of m-Ary Challenges for RFID Distance Bounding Protocol

Abstract

In this paper, we propose an RFID distance bounding protocol that uses m-ary challenges. Recently, Kim and Avoine proposed two distance bounding protocols with mixed challenges that are pre-determined or random. We generalize the first scheme of Kim and Avoine's random scheme as a distance bounding protocol with m-ary challenges. The generalized formula for success probabilities for mafia fraud and distance fraud attacks is derived. Our scheme using m-ary challenges reduces the mafia fraud success probability from (3/4)ⁿ for m=2 to (7/16)ⁿ for m=4 and the distance fraud success probability from $(1-\frac 1 4 \cdot P_r)^n$ for m=2 to $(1 - \frac {189}{256} \cdot P_r)^n$ for m=4, where P_r is the probability that a challenge is random.