Multi-user quantum key distribution network apparatus

Abstract

The invention aims at designing a quantum key distribution network scheme that is easy to construct, enables the cost to be low, has high anti-interference capability, and is capable of realizing communication between any users and overcoming the defect caused by imperfect performances of parts of key devices. The provided scheme has the following advantages: firstly, combination of quantum channels, phase modulators, 90-degree faraday rotator mirrors is used, the birefrigent effect of the optical fiber and the optical device can be compensated automatically, the system stability is enhanced, and the anti-interference capability of the quantum key distribution system is improved; secondly, on the basis of the optical switch control, quantum key sharing between any two users in a network can be realized; thirdly, besides the master control side, each controlled side only needs one phase controller, faraday rotator mirror, and attenuator, so that the networking cost is substantially reduced; and fourthly, the master control side only serves as the auxiliary communication end in the network and will publish modulation information and detection results after communication completion, so that immunity to an attack strategy caused by the imperfect performance of the detector in the actual system can be realized.

Description

technical field [0001] The invention relates to the technical field of optical fiber transmission secure communication, in particular to an implementation scheme in multi-user quantum key distribution. 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, the classical cryptosystem is 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 based on the BB84 protocol for the first time, 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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