Multi-party Quantum Key Agreement Protocol with Authentication

Utilizing the advantage of quantum entanglement swapping, a multi-party key agreement protocol with authentication is proposed. In this protocol, semi-trusted third party introduced, who prepares Bell states, and sends one particle to multiple participants respectively. After that can share Greenberger-Horne-Zeilinger state by swapping. Finally, these measure particles in their hands obtain an key. Here, classical hash function Hadamard operation are utilized authenticate identity participants. The correlations GHZ states ensure security proposed protocol. To illustrated it detailly, against common attacks analyzed, which shows secure theory.