Quantum key distribution (QKD) offers an approach for secure communication over quantum channels, based on the principles of quantum mechanics. However, the inevitable imperfections in QKD systems can introduce critical vulnerabilities, posing significant challenges to the deployment of QKD in terms of both practical security and performance. In this work, we present a comprehensive security analysis of QKD in the practical scenarios involving imperfections in modulation spaces. Specifically, our analysis focuses on the imperfections related to encoding, intensity modulation, and their characterization. We provide a unified framework based on the operator dominance method to overcome these issues and achieve a tight estimation of the secret key rate (SKR). The simulation results show that the SKR in practical scenarios, with parameters characterized from commercial QKD systems, closely matches the SKR under ideal conditions. In the finite case, the maximum transmission distance can reach up to 250 km with total pulse number $N=10^{12}$ and the SKR closely approaches the asymptotic limit up to 250 km with $N=10^{14}$ . This validates the robustness of our method against imperfections in state preparation and characterization. Furthermore, the feasibility and robustness of method in measurement-device-independent (MDI) QKD have also been demonstrated. Our analysis not only promotes advancements in enhancing practical security and performance but also highlights the feasibility of deploying QKD for actual applications.Quantum key distribution (QKD) offers an approach for secure communication over quantum channels, based on the principles of quantum mechanics. However, the inevitable imperfections in QKD systems can introduce critical vulnerabilities, posing significant challenges to the deployment of QKD in terms of both practical security and performance. In this work, we present a comprehensive security analysis of QKD in the practical scenarios involving imperfections in modulation spaces. Specifically, our analysis focuses on the imperfections related to encoding, intensity modulation, and their characterization. We provide a unified framework based on the operator dominance method to overcome these issues and achieve a tight estimation of the secret key rate (SKR). The simulation results show that the SKR in practical scenarios, with parameters characterized from commercial QKD systems, closely matches the SKR under ideal conditions. In the finite case, the maximum transmission distance can reach up to 250 km with total pulse number $N=10^{12}$ and the SKR closely approaches the asymptotic limit up to 250 km with $N=10^{14}$. This validates the robustness of our method against imperfections in state preparation and characterization. Furthermore, the feasibility and robustness of method in measurement-device-independent (MDI) QKD have also been demonstrated. Our analysis not only promotes advancements in enhancing practical security and performance but also highlights the feasibility of deploying QKD for actual applications.

quant-pharXiv:2610.11438Physical Review AOct 9, 20260 citations

Secure Multi-Party Computation Protocol Based on Quantum Key Distribution

Jincheng Zhang

This paper presents a novel protocol for secure multi-party computation (MPC) leveraging the security of quantum key distribution (QKD). The core claim is to design a protocol that guarantees secure computation among multiple participants. The proposed mechanism utilizes the inherent security of QKD to construct a framework for secure multi-party computation. This approach addresses the limitations of traditional MPC protocols that often rely on computationally intensive assumptions, offering a potentially more robust solution in the face of evolving cryptographic threats. The protocol details the steps involved in generating a shared secret key through QKD, followed by the secure computation process based on the key. We outline the mathematical foundations and formalize the protocol's components, demonstrating its feasibility and potential advantages. The protocol is designed to be adaptable and scalable, offering a viable route toward secure distributed computing in quantum-enhanced environments.This paper presents a novel protocol for secure multi-party computation (MPC) leveraging the security of quantum key distribution (QKD). The core claim is to design a protocol that guarantees secure computation among multiple participants. The proposed mechanism utilizes the inherent security of QKD to construct a framework for secure multi-party computation. This approach addresses the limitations of traditional MPC protocols that often rely on computationally intensive assumptions, offering a potentially more robust solution in the face of evolving cryptographic threats. The protocol details the steps involved in generating a shared secret key through QKD, followed by the secure computation process based on the key. We outline the mathematical foundations and formalize the protocol's components, demonstrating its feasibility and potential advantages. The protocol is designed to be adaptable and scalable, offering a viable route toward secure distributed computing in quantum-enhanced environments.

Aug 28, 20260 citations

On the security and the performance of quantum key distribution

Víctor Zapatero

Feb 11, 20220 citations

Distributed Bayesian Inference via Quantum Key Distribution

Jincheng Zhang

This paper proposes a novel approach to distributed Bayesian inference leveraging the principles of Quantum Key Distribution (QKD). The core idea is to utilize QKD for secure distribution of random numbers across nodes in a distributed Bayesian network, thereby facilitating joint inference while maintaining data privacy. We outline a framework where QKD ensures the confidentiality of the random number generation process, crucial for the accurate construction of probability distributions necessary for Bayesian inference. The resulting system addresses the challenges of secure data aggregation and inference in distributed environments, offering a potentially scalable and robust solution. This research explores the theoretical foundations and potential benefits of integrating QKD with Bayesian methods, paving the way for new paradigms in secure distributed data analysis. The key mathematical components and operational principles are presented, demonstrating the feasibility of this approach.This paper proposes a novel approach to distributed Bayesian inference leveraging the principles of Quantum Key Distribution (QKD). The core idea is to utilize QKD for secure distribution of random numbers across nodes in a distributed Bayesian network, thereby facilitating joint inference while maintaining data privacy. We outline a framework where QKD ensures the confidentiality of the random number generation process, crucial for the accurate construction of probability distributions necessary for Bayesian inference. The resulting system addresses the challenges of secure data aggregation and inference in distributed environments, offering a potentially scalable and robust solution. This research explores the theoretical foundations and potential benefits of integrating QKD with Bayesian methods, paving the way for new paradigms in secure distributed data analysis. The key mathematical components and operational principles are presented, demonstrating the feasibility of this approach.

Sep 7, 20260 citations

Quantum Key Distribution: from Principles to Practicalities

Dagmar Bruß, Norbert Lütkenhaus

arXiv:quant-ph/9901061Applicable Algebra in Engineering Communication and ComputingMay 1, 200029 citations

N=10^{12}

and the SKR closely approaches the asymptotic limit up to 250 km with

N=10^{14}

. This validates the robustness of our method against imperfections in state preparation and characterization. Furthermore, the feasibility and robustness of method in measurement-device-independent (MDI) QKD have also been demonstrated. Our analysis not only promotes advancements in enhancing practical security and performance but also highlights the feasibility of deploying QKD for actual applications.