Quantum Multi-party Private Comparison Protocol using d-dimensional Bell States

In this paper, we present a quantum private comparison(QPC) protocol for n parties. N parties can compare whether their information are equal or not in one execution of our protocol. With the help of a semi-honest third party (TP), the quantum multi-party private comparison protocol uses the d-dimensional Bell states as the information carriers and uses a special property of the d-dimensional Bell states to perform the equality comparison. Various kinds of outside attacks and participant attacks are discussed in detail. One party cannot learn any information about the others’ private information except the comparison result. The TP cannot learn any information about the private information except the comparison result.