Multi-party quantum private comparison protocol with n-level entangled states

In this paper, two multi-party quantum private comparison (MQPC) protocols are proposed in distributed mode and traveling mode, respectively. Compared with the first MQPC protocol, which pays attention to compare between arbitrary two participants, our protocols focus on the comparison of equality for (n) participants with a more reasonable assumption of the third party. Through executing our protocols once, it is easy to get if (n) participants’ secrets are same or not. In addition, our protocols are proved to be secure against the attacks from both outside attackers and dishonest participants.