Research On Quantum Dialogue Protocols

Quantum dialogue is two-way quantum secure direct communication; itsimplementation is built on the relevant physics knowledge. It has a lot of advantagesand higher security compared with the traditional cryptography whose establishment isthe mathematical problems, such as large integer factoring and discrete logarithm. Inthis paper, based on the study of quantum cryptographic protocols and relatedtechnology, we analyzed the quantum secure direct communication and quantumdialogue and the implementation of them. This paper focuses on the quantum dialogue.The main points of this paper are as follows:(1) By analyzing the existing quantum cryptographic protocols and theirimplementation process, we improve the protocol that has the problem of informationleakage (Quasi-secure quantum dialogue using single photons. Sci. China-Phys. Mech.Astron. Oct. 2007. Vol. 50. 558-562), and improve its security and increase theutilization of the particles through the method of quantum encryption. Moreover thismethod can be applied to the protocols that are realized similarly.(2) Based on the analysis of the principles and techniques in the quantum keydistribution and quantum secret sharing protocols with the Bell states, we propose a newmethod to implement quantum dialogue. With this method a secure and efficientquantum dialogue protocol can be realized by using entangled photons and reordertechnology.(3) Based on the study of quantum dialogue protocols with the Bell states, wegeneralized the method of using entangled photons and reorder technology to the caseof using three dimensional Bell states, i.e. two-qutrit entangled states. Both theprotocols are resistant to the typical attacks that can be taken by the eavesdropper. Thetypical attacks including the intercept/resend attack, Trojan horse attacks andentanglement attacks. Both the protocols are easy to be achieved within the existingtechnology.