An entanglement-based quantum dialogue protocol [Phys. Lett. A 328(2004)6] is proven to be insecure: that is, in the protocol an eavesdropper can steal the secret messages without being detected provided that he/she adopts the intercept-and-resend attack strategy. We modify the protocol, i.e. in the control mode, by introducing and randomly choosing two sets of measuring basis: the intercept-and-resend attack can be accordingly detected. Hence, within the present version two users can securely and simultaneously exchange their secret messages.
- MAN Zhong-Xiao, ZHANG Zhan-Jun, LI Yong. Quantum Dialogue Revisited[J]. CPL, 2005, 22(1): 22-24.