Quantum key distribution network device and method of master-slave structure

Abstract

The invention discloses a quantum key distribution network device and method of a master-slave structure. A master optical path of the quantum key distribution network device is composed of a single photon source, a polarization controller PC, an optical circulator, a coupler / beam splitter, a four-port optical polarization beam splitter / combiner, an optical switch and a quantum channel. A master control party and a slave control party of the network are connected through a quantum channel formed by an optical switch and an optical fiber, and an optical circulator reflection output end of the master control party and an output end of a coupler / beam splitter are respectively connected with a single-photon detector; one output light port of the coupler / beam splitter is connected with one phase controller to form an information loading part; two output ports of the coupler / beam splitter are respectively connected with two input ports of the optical switch to form a network control part; and the slave control party forms an information loading part by an attenuator, a phase modulator and a 90-degree rotating Faraday reflector which are sequentially connected with the quantum channel. Parallel polarization and vertical polarization of signal pulses are utilized to realize communication three-party quantum key distribution among different levels.

Description

technical field [0001] The invention relates to the technical field of optical fiber transmission secure communication, in particular to a master-slave quantum key distribution network device and method. Background technique [0002] Classical cryptography is based on mathematical problems such as prime factorization of large numbers. With the advancement of computer computing speed, especially the emergence of quantum computers, classical cryptosystems are no longer unbreakable. Quantum cryptography communication is based on quantum mechanics, and is currently the only option recognized by the scientific community to achieve absolutely secure communication in the future. [0003] The research of quantum cryptography communication mainly focuses on quantum key distribution. Since 1989, Bennett et al. successfully completed a demonstration experiment in free space for the first time based on the BB84 protocol, thus setting off a climax of quantum key distribution experiment...

AI Technical Summary

Problems solved by technology

With the development of point-to-point communication systems, although quantum key distribution is theoretically absolutely safe, in actual systems, due to some errors between the used devices and ideal devices, this will lead to the existence of problems in the actual point-to-point quantum cryptography communication system. Dangerous loopholes in information leakage. Since 2007, many international groups have successfully stolen the keys of commercial point-to-point quantum communication systems (mainly the clavis2 system of IDQ Company) by using the loopholes in the actual quantum communication system. It is found that these attack methods on point-to-point quantum communication research will also affect the security of existing quantum communication networks

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