Protocol Design Of Bidirectional Identity Authentication Based On Bipartite Entangled State

As an important branch of quantum cryptography,quantum identity authentication plays an important role in protecting the security of quantum communication.Identity authentication technology can verify the authenticity of all parties in communication and prevent malicious attackers from impersonating legitimate users.Meanwhile it can verify the integrity of the information transmitted in the communication process and the reliability of the sender of the information,which can avoid malicious attackers to forge or modify the transmitted information.With the improvement of computing power of computer,especially the development of quantum computer,the security of classical identity authentication protocol based on computing mathematical complexity is facing a severe challenge.Therefore,it is necessary to study quantum identity authentication protocol which can resist the attack of the quantum computer.After analyzing the existing quantum identity authentication protocols,two quantum identity authentication protocols based on two-particle entangled state are proposed.The main contents in this thesis are as follows:(1)Considering the difficulty in preserving entangled particles for a long time,a quantum identity authentication protocol of sharing classical information types is proposed.In the proposed protocol,we use the Bell state as the quantum resource,and there is a semi-trusted third-party who prepares the quantum resource and transmits these prepared particles to two users.The two legitimate users randomly select a particle sequence and performs the quantum unitary operation according to the secret key respectively,while the untrusted third-party doesn't need to perform any unitary operations.Then,the two users and the third-party respectively perform the Bell base measurement to realize identity authentication between the two users.Security analysis shows that the proposed protocol can not only effectively prevent various external attack methods,but also prevent the untrusted third-party from using illegal operations to steal the secret keys shared between legitimate users.(2)Most existing protocols verify one bit of classical information with one Bell state.In order to save quantum resources,we propose a quantum bidirectional authentication protocol based on Bell state.The proposed protocol can verify two bits of classical information with one Bell state,which can effectively reduce the consumption of quantum resources.Without the assistance of the third-party authentication authority,the two users can achieve two-way simultaneously identity authentication by executing the authentication process once,which is more efficient than the existing quantum authentication protocol.The two users don't need to perform the quantum unitary operation,but only performs the single particle measurement and the classical XOR operation while in authentication process,which makes the proposed protocol easier to implement.