Multi-party Quantum Secure Direct Communication

A protocol for three-party quantum secure direct communication using entanglement states is proposed. In this protocol, three participants simultaneously exchange their messages. The protocol is shown to stand against the intercept-and-resend attack, the intercept-and-measure attack, the intercept-and-entangle auxiliary attack and the denial-of-service attack. It can be generalized to N-party case that is feasible.