Multiparty Quantum Private Comparison of Size Relation Based on Single-Particle States

In order to reduce resource consumption and improve transmission efficiency, in this paper, using single-particle states, a multiparty quantum privacy comparison size relationship (QPCSR) protocol is proposed. Without leaking the compared private message, the blinded secret integer is encoded into the relative phase of single-particle by performing unitary operation. After each of the transformed quantum states has been measured, respectively, the comparison result of n participants' secret integers is obtained. Security analysis shows that this protocol not only resists outside attack and participant attack, but also resists the semi-honest third-party (TP) attack. Compared with the other similar quantum privacy comparison equal relationship (QPCER) protocols, the proposed protocol has better flexibility and universality; compared with the other similar QPCSR protocols, it has lower resource consumption and higher communication efficiency.