具有双向认证功能的多方量子密钥分发

Abstract

Based on the entanglement feature of Greenberger-Horne-Zeilinger states, a multi-user quantum key distribution with mutual authentication is proposed. In the protocol, a semi-trusted third party, who may misbehave on its own but will conspire with none of the participants, is introduced to help arbitrary two users on a quantum network to achieve this secure task. Firstly, the third party prepares a three-particle entangled state. Then, he keeps one particle in his hand, and sends two particles to these two users respectively. Meanwhile, a keyed one-way hash function is utilized to generate an authentication message, in terms of which three parties respectively make an appropriate single-particle measurement on the particles in their hands. According to the measurement results, the third party can verify the identity of one user. It implies that one user is able to authenticate the other user with the assistance of the third party. After that, two participants use the remainder measurement results to generate a common session key. Moreover, the practical implementation of the presented protocol is discussed, which illustrates that this protocol is feasible under the current techniques. In the end, the security of the presented protocol is analyzed. It is shown that this protocol is secure in theory by proving that the presented protocol can stand against several common attacks.