Analysis of unilateral distance bounding protocol with mixed predefined and bidirectional challenges over a noisy communication channel

Distance bounding protocols have been proposed to prevent a relay attack on RFID systems. In a distance bounding protocol, an upper bound for the physical distance between two communication parties executing the protocol (a verifier and a prover) is computed by the verifier. Recently, Park et al proposed a distance bounding protocol (we call PNKYL) which utilizes mixed predefined and bidirectional challenges. It is well known that PNKYL provides the best security level for distance bounding protocols without a final confirmation message. Since distance bounding protocols and RFID systems are highly sensitive to noise, in this paper, PNKYL is analyzed to obtain the rejection probability of a valid prover due to channel errors. The simulation and analysis results show that increasing the probability of erroneous transmission has a great effect on increasing the rejection probability of a valid prover. To address this problem, we add two parameters (T₁ and T₂) to the protocol as the number of acceptable errors by the prover and the verifier respectively. The analytical results demonstrate, with the proper selection of these two parameters, PNKYL can provide an appropriate performance in a known noisy environment.