A class of protocols for multi-party quantum private comparison based on traveling mode

Abstract

Multi-party quantum private comparison (MQPC) enables $$n (n\ge 2)$$ parties to compare the equality of their private secrets without leaking them. In this paper, a class of MQPC protocols are proposed based on single-particle states and maximally entangled states. With the help of a semi-honest third party, our protocols can compare the equality of n parties’ private secrets. Our protocol uses single-particle states and a class of maximally entangled states as the information carriers, which means that our protocol has flexibility in the selection of quantum states compared with all previous protocols; after all, each of the previous protocols only uses a specific quantum state. In addition, our protocols adopt traveling mode, which can significantly reduce resource consumption. What is more, the qubit efficiency of each of our protocols can reach 100%, which is much higher than that of all previous MQPC protocols. We show that our protocols are secure against the outside and participant attacks.