Measurement-device-independent quantum dialogue protocol with bidirectional identity authentication

Quantum dialogue (QD) realizes the real-time secure bidirectional quantum communication. Measurement-device-independent (MDI) QD can resist all possible attacks focusing on the imperfect measurement devices and enhance QD’s practical security. However, in practical applications, any secure communication requires identity authentication as a prerequisite. In this paper, we propose an MDI QD protocol with bidirectional identity authentication. The practical communication parties can first authenticate the identity of each other simultaneously before the message exchange. In theory, our MDI QD protocol has unconditional security and the communication parties can exchange 1.5 bits of messages in each communication round with linear optical Bell state measurement. We numerically simulate the secrecy message capacity of our MDI QD protocol. Our protocol has two advantages. First, it can effectively resist the impersonation attack and enhance MDI QD’s practical security. Second, it does not require keys to assist the message exchange and has relatively high efficiency. Our protocol has application potential in the future quantum communication field.