Quantum Secret Sharing And Quantum Authentication Research

Built on the basis of quantum calculation, quantum cryptography is a new research field combining quantum mechanics and cryptographic communication. At present, the research of quantum cryptography has aroused the widespread interest among people and has made important progress in theory and practice.The quantum secret sharing and quantum identity authentication is discussed in this paper.At first, this paper elaborated the physics basis of quantum cryptography, analyzed the distribution agreement of quantum secret key and introduced the basic theory and process of quantum teleportation.Secondly, this paper discussed the quantum secret sharing. By the GHZ state and W state of three-particle entanglement respectively, the plan of the single quantum and quantum secret sharing was completed, and the differences between the two entangled states were compared. Meanwhile, the paper analyzed how to finish the double-quantum-bit secret key sharing scheme by manipulating four and five-particle entanglement GHZ. So this paper made use of five-particle entanglement GHZ to put-through the three-particle entanglement teleportation in order to realize the three-quantum secret sharing. Compared with the program in the fifth section in third chapter, it enhanced the quantum transmission without increasing the number of particles, and formed a theoretical basis for transmitting more quanta in quantum secret sharing.At last, this paper considered the quantum identity authentication system. Based on the analysis of remote point-to-point quantum identity authentication, there are many contents were discussed, such as quantum identity programs of the use of measuring basic coding, random interlude technology and arresting interlude technology. Moreover the advantages and the disadvantages among them were presented also. In addition, the scheme of quantum identity authentication was analyzed on the basis of arresting interlude technology and distributing secret key by EPR entanglement. Furthermore, the different methods of the quantum secret key expansion were discussed, and a negation making method and an insertion method were proposed too. In addition, this chapter analyzed the quantum identity authentication technology in the network environment and brought forward a scheme of quantum identity authentication based on the swapping of the EPR entanglement and analyzed its security. Thus a scheme of sharing secret key string between two sides in the distributed network environment was presented. It made use of the entanglement swapping to authenticate the identity. Finally, the feasibility of adopting different technology to distribute EPR entanglement was analyzed.