A distance bounding protocol enables one entity to determine an upper bound on the physical distance to the other entity as well as to authenticate the other entity. It measures the round-trip time of exchanged messages that normally consist of n rounds of a single-bit challenge and a single-bit response. Let FARMand FARDbe the false acceptance rate against mafia fraud attack and distance fraud attack, respectively. Brands and Chaum designed the first distance bounding protocol that has (FARM, FARD) = ((½)n, (½)n). Recently Yum et al. proposed a flexible distance bounding protocol, in IEEE Communications Letters, asserting that its false acceptance rate (FARM, FARD) can be chosen from ((½)n, (½)n) to ((¼)n, (3/4)n). However, we introduce a new attack that achieves a higher false accep tance rate, where (FARM, FARD) varies from ((½)n, (½)n) to ((½)n, (½)n/2).
Current quantum secure direct communication (QSDC) protocols guarantee communication security by estimating the error rates of photons in the X and Z bases. This take the reference frame calibration between communicating parties as a necessary prerequisite. However, in mobile communications scenarios, achieving continuous and accurate reference frame calibration poses significant challenges. To address this issue, this paper proposes a reference-frame-independent (RFI) QSDC protocol. This protocol only requires ensuring the calibration accuracy of one direction of the reference frame, while allowing a misalignment angle
β in the other two directions. To improve the protocol's robustness against reference frame fluctuations, we introduce a
β-independent parameter C into the security analysis framework and rederive the protocol's security bounds. Additionally, we construct a system model and optimize the pulse intensity of the signal states, enabling the protocol to achieve optimal performance under each level of channel attenuation. At an attenuation of 10 dB (corresponding to a communication distance of 25 km), the secrecy message capacities for $β= 0^{ \circ} $ and $45^{ \circ} $ are
8.765×10−6 bit/pulse and
4.150×10−6 bit/pulse, respectively. Compared with the single-photon-based QSDC, the communication distance of the protocol proposed in this paper is significantly extended. When $β= 0^{ \circ} $ and $45^{ \circ} $, the maximum transmission distances of the RFI QSDC protocol are 27.875 km and 26.750 km, which is about 155.9 % and 149.7 % of that of the single-photon-based QSDC protocol.
We present a distance bounding (DB) protocol that employs quantum-bits (qubits) in the implementation of the rapid-bit exchange (a.k.a., challenge-response) phase, instead of classical bits. This is not the first attempt at using qubits in a DB protocol, as Abidin et al. proposed a way to implement DB protocols using qubits in RFIDSec 2016 [1]. We improve upon Abidin et al.'s protocol and make it resistant to photon number splitting attacks. In addition, our new protocol eliminates the need for communication from the prover to the verifier in the last authentication phase, which is necessary in the protocol by Abidin et al.