Single-state semiquantum private comparison based on Bell states

Abstract

In this paper, a novel semiquantum private comparison (SQPC) protocol based on single kind of Bell states is proposed, which allows two classical parties to judge the equality of their private inputs securely and correctly under the help of a semi-honest third party (TP) who possesses complete quantum capabilities. TP is allowed to misbehave on her own but cannot conspire with anyone else. Our protocol needs none of unitary operations, quantum entanglement swapping or the reordering operations. Moreover, our protocol only needs to prepare single kind of Bell states as initial quantum resource. Detailed security analysis turns out that our protocol is secure against various outside and participant attacks. Compared with most of the existing SQPC protocols based on Bell states, our protocol is more feasible in practice.