Research On Data Reconciliation And Software Design In Quantum Key Distribution System

Shannon’s information theory shows that G.Vernam’s one-time-one-pad scheme can guarantee secure communication. And from this scheme we can see that the key should be discarded once used, therefore sufficient keys are needed for data encryption or decryption. Quantum Key Distribution (QKD) system can achieve safe and effective distribution of a large number of keys, thus protecting the data security and privacy combining with the one-time-one-pad scheme. The research in this paper is about the coordination of data and system software which have closely related with quantum key distribution. This paper provides valuable reference for practical quantum key distribution technology and guarantees the security of data transmission.First, this paper introduces the basic steps of classic data coordination algorithms, including the dichotomy, cascading and hamming error correction coding. We simulate dichotomy performance to verify the efficiency of dichotomy when the QBER of packet is not same:the lower bit error rate is, the higher the effectiveness of coordination is; but when the error rate is high, since the keys are recursively grouped and compared, discarded data and traffic increase, therefore the coordination efficiency decreases.Secondly, based on the classical data reconciliation algorithm, this paper introduces a data reconciliation algorithm base on Low-density Parity-Check (LDPC) codes with higher efficiency and better performance of error correction. When it comes to the data reconciliation algorithm base on LDPC codes, this paper focuses on the basic steps of the algorithm and R-U code. Then, after the software modules of data reconciliation based on LDPC have been achieved, the performance has been simulated. From the simulation results, we can see that the algorithm is feasible and effective for correcting errors, and it is better than coordination of dichotomous data algorithm, so it can provide better guarantee for security in subsequent data transmission.Third, this paper designs new modular about the software part of quantum key distribution system. Quantum key distribution system is composed of management modules, application modules and module QKD, and management module mainly completes some related scheduling between key pool, QKD modules and application modules, and as an interface between the quantum network server and the entire system for interactive information. This design workflow for each module and the information transmission mechanisms between modules, and according to information transfer case between modules, each module’s processes are designed and interprocess communication has been described.Finally, this paper summarize the full text. On the basis of this paper and development direction of quantum key distribution, this paper prospect the next step of work.