Romanian Cyber Security Journal / Spring 2025, No. 1, Vol. 7

Quantum Networks with Entanglement-Based Quantum Key Distribution. Implications in Cyber Security

Sorin SOVIANY, Cristina-Gabriela GHEORGHE, Maria GHEORGHE-MOISII

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Abstract

The paper addresses the development of quantum networks (QNs) with entanglementbased Quantum Key Distribution (QKD) protocols. The entanglement (the correlation among the quantum states of several particles) is an essential principle of quantum mechanics. This property has a major impact on the fields of application of QKD systems, the secured cryptographic key exchange and passive attack detection, while it can also be applied in quantum teleportation. Starting from the existing achievements in Europe (a QN for connecting several cities in Randstad, one of the main metropolitan regions in the Netherlands), a case study for a simulated entanglement-based QN is presented, including an ideal scenario (with noiseless QKD) and a nonideal one (with noisy QKD). The experimental settings are differentiated through the link and node fidelity. The simulation process produces general statistics, sender statistics, receiver statistics, the QBER (Quantum Bit Error Rate) and also the raw keys as generated by the entanglement-based protocol. No post-processing (non-quantic) phase is considered for the analyzed setting. Such simulations are useful for properly adjusting the design of a QN while taking into account its expected performance with respect to the non-ideal use-cases with errors that could be caused by an imperfect hardware or by potential eavesdropping actions.

Keywords

Quantum networks, Quantum Key Distribution, Cyber Security, Entanglement