Implementation and topology of quantum key distribution networks

Sheila Cobourne

Jincheng Zhang

This paper investigates the optimization of topological structures within quantum key distribution (QKD) protocols. The core claim is that strategic topological optimization can significantly enhance key distribution efficiency and security. The proposed methodology leverages analytical analysis of quantum network topologies to identify optimal key distribution schemes. Specifically, we explore how the arrangement of nodes and connections within a quantum network impacts the performance of protocols like BB84 and E91. The underlying mechanism involves utilizing the inherent properties of quantum entanglement to achieve highly efficient and secure key exchange. We present a framework for evaluating different topological configurations based on metrics such as key generation rate, channel loss, and eavesdropping detection probability. The results demonstrate a clear correlation between optimized topologies and improved QKD performance. Furthermore, we address the challenges associated with implementing these optimized topologies, including considerations for quantum repeater placement and network scalability. This research contributes to the advancement of practical QKD systems by providing a rigorous approach to topological design.

Jincheng Zhang

This paper presents a novel quantum key distribution (QKD) protocol designed specifically for scalable photonic networks. The protocol leverages the inherent advantages of a multi-hop, all-topological architecture to overcome the limitations of traditional QKD systems regarding key transmission distance and rate. We propose a scheme utilizing quantum entanglement and state transformations within the network to facilitate distributed key generation and secure key distribution. The core innovation lies in the network topology itself, which allows for robust error correction and eavesdropping detection, ultimately leading to a highly secure and high-throughput quantum communication system. The theoretical analysis demonstrates the protocol's resilience to various attack scenarios and highlights its potential for practical implementation in large-scale quantum networks.

Eleftherios Moschandreou

Fabio Garzia, Roberto Cusani

The purpose of this paper is to compare the performance of four passive optical network topologies in implementing multi-user quantum key distribution, using 3 protocols proposed by quantum cryptography (B92, EPR, and SSP). The considered networks are the passive-star network, the optical-ring network based on the Signac interferometer, the wavelength-routed network, and the wavelength-addressed bus network. The quantum bit-error rate and sifted key rate for each of these topologies are analysed to determine their suitability for providing quantum key distribution-service to networks of various sizes. The efficiency of the three considered protocols is also determined.

Masahiro Takeoka