Optical fibre networks are advancing rapidly to meet growing traffic demands. Security issues, including attack management, have become increasingly important for optical communication networks because of the vulnerabilities associated with tapping light from optical fibre links. Physical layer security often requires restricting access to channels and periodic inspections of link performance. In this paper, we report how quantum communication techniques can be utilized to detect a physical layer attack. We present an efficient method for monitoring the physical layer security of a high-data-rate classical optical communication network using a modulated continuous-variable quantum signal. We describe the theoretical and experimental underpinnings of this monitoring system and the monitoring accuracy for different monitored parameters. We analyse its performance for both unamplified and amplified optical links. The technique represents a novel approach for applying quantum signal processing to practical optical communication networks and compares well with classical monitoring methods. We conclude by discussing the challenges facing its practical application, its differences with respect to existing quantum key distribution methods, and its usage in future secure optical transport network planning.

光纤网络正在迅速发展，以满足不断增长的流量需求。由于与从光纤链路分接光相关的漏洞，包括攻击管理在内的安全问题对于光通信网络变得越来越重要。物理层安全通常需要限制对通道的访问并定期检查链路性能。在本文中，我们报告了如何利用量子通信技术来检测物理层攻击。我们提出了一种使用调制的连续可变量子信号来监控高数据速率经典光通信网络的物理层安全的有效方法。我们描述了该监测系统的理论和实验基础以及不同监测参数的监测精度。我们分析了其未放大和放大光链路的性能。该技术代表了一种将量子信号处理应用于实际光通信网络的新颖方法，并且与经典的监测方法相媲美。最后，我们讨论了其实际应用所面临的挑战、其与现有量子密钥分配方法的差异以及其在未来安全光传输网络规划中的使用。