Quantum Key Distribution (QKD) is a foundational cryptographic protocol that ensures information-theoretic security. However, classical protocols such as BB84, though favored for their simplicity, offer limited resistance to eavesdropping, and perform poorly under realistic noise conditions. Recent research has explored the use of discrete-time Quantum Walks (QWs) to enhance QKD schemes. In this work, we specifically focus on a one-way QKD protocol, where security depends exclusively on the underlying Quantum Walk (QW) topology, rather than the details of the protocol itself. Our paper introduces a novel protocol based on QWs over a hypercube topology and demonstrates that, under identical parameters, it provides significantly enhanced security and noise resistance compared to the circular topology (i.e., state-of-the-art), thereby strengthening protection against eavesdropping. Furthermore, we introduce an efficient and extensible simulation framework for one-way QKD protocols based on QWs, supporting both circular and hypercube topologies. Implemented with IBM's software development kit for quantum computing (i.e., Qiskit), our toolkit enables noise-aware analysis under realistic noise models. To support reproducibility and future developments, we release our entire simulation framework as open-source. This contribution establishes a foundation for the design of topology-aware QKD protocols that combine enhanced noise tolerance with topologically driven security.

翻译：量子密钥分发（QKD）是一种确保信息论安全的基础密码协议。然而，经典协议如BB84虽然因其简洁性而备受青睐，但其抗窃听能力有限，且在现实噪声条件下表现不佳。近期研究探索了利用离散时间量子行走（QWs）来增强QKD方案。本文专门研究一种单向QKD协议，其安全性完全依赖于底层量子行走（QW）的拓扑结构，而非协议本身的细节。我们提出了一种基于超立方体拓扑的量子行走新协议，并证明在相同参数下，该协议相比环形拓扑（即当前最优方案）能显著提升安全性与抗噪性，从而增强对窃听攻击的防护。此外，我们为基于量子行走的单向QKD协议引入了一个高效且可扩展的仿真框架，支持环形与超立方体两种拓扑结构。该工具包基于IBM量子计算软件开发套件（即Qiskit）实现，能够在现实噪声模型下进行噪声感知分析。为支持可重复性与未来研究，我们将完整的仿真框架开源发布。此项工作为设计兼具增强抗噪能力与拓扑驱动安全性的拓扑感知QKD协议奠定了基础。