Research And Application Of Security Of Quantum Key Distribution Decoy BB84 Protocol

In traditional cryptography,whether it is a symmetric cryptosystem or an asymmetric cryptosystem,its security depends on mathematically complex and difficult problems.If the computing resources required to crack the cryptographic system far exceed the computing resources possessed by the current computer,the cryptographic system can be considered to have computational security.In the case of quantum computers and quantum algorithms,encryption algorithms based on computational complexity of traditional cryptography will no longer be safe.However,with the development of quantum technology,the advent of quantum computers has gradually become possible.At the same time,various efficient quantum algorithms based on quantum computers will also be realized.The "One-TimePad" cryptosystem is currently the only classic cryptosystem proven to guarantee absolute security.However,the "One-Time-Pad" cryptosystem requires the two parties to exchange long enough and truly random key information,the traditional key distribution system cannot satisfy the above two conditions.Faced with the threat of quantum computers,we urgently need a cryptographic system that does not depend on computational security.Quantum secret communication was born in this situation.Quantum key distribution technology can realize the distribution of a large number of random keys between the two parties in communication.Its security depends on the basic principles of quantum physics,so it has theoretical unconditional security.Combining the quantum key distribution technology with the " OneTime-Pad " cryptosystem,unconditionally secure quantum secret communication can be achieved,but in the practical application of the quantum key distribution technology,due to factors such as the imperfection of the device,its security will be affected.This article first introduces the research status and basic theory of quantum key distribution,and then does the following research on quantum key distribution technology:(1)If there is an eavesdropper in the BB84 protocol to carry out an attack,it will cause a significant change in the bit error rate.When the bit error rate exceeds a certain threshold,it can be considered that there is an eavesdropper.However,in practice,the bit error rate deviates from the theoretical value.Judging whether there is an eavesdropper based on the theoretical threshold will cause security problems.In this situation,we analyzed the theoretical standards of the BB84 protocol and the decoy BB84 protocol for the detection and measurement forwarding attack and the photon number split attack.Combining the statistical fluctuation problems in practice,we proposed two protocols for the attack in practical applications Detection method,combined with relevant data for calculation.(2)The ideal quantum key distribution system requires that every component in the system is unconditionally safe,which requires that the identity authentication protocol of the quantum key distribution system is also unconditionally safe.The key generated by the quantum key distribution has true randomness.Combining the key with true randomness and the hash function can realize an unconditionally safe identity authentication protocol.We combine the identity authentication algorithm based on the Toeplitz matrix with the traditional Kerberos protocol,and propose a quantum key-based Kerberos protocol,and show that it has theoretical unconditional security.