An Efficient Quantum Private Comparison Protocol Based on Conjugate Coding

Abstract

Quantum private comparison (QPC) allows at least two participants who do not trust each other to compare whether their secret data are the same while maintaining data privacy. In order to improve the qubit efficiency and avoid using entangled state, we propose an efficient quantum private comparison based on conjugate coding. Our protocol only uses a set of qubits which are X-basis or Z-basis, as the information carrier. Participants use conjugate coding rules to encode their information into these qubits, which is to make the qubit efficiency of the protocol reach 100%. And these qubits transmitted through a circular path, which can effectively reduce resource consumption. Moreover, decoy photon technology and quantum key distribution (QKD) are used to ensure the security of information, making both external and internal attacks invalid.