Digital Twin of Optical Networks: A Review of Recent Advances and Future Trends

Digital twin (DT) has revolutionized optical communication networks by enabling their full life-cycle management, including planning, prediction, optimization, upgrade, and troubleshooting. The rapid development of DT applications for optical networks, from concepts and architecture to simulation and experimental validation, has been exceptional. As a real-time virtual replica of physical optical networks, the DT of optical networks can be divided into three parts: real-time monitoring, mirror modeling, and automatic control. Recent advancements in each part have individually propelled the network towards intelligence and automation. In this paper, we make a comprehensive survey on this timely topic and illustrate the principal evolutions within these three parts. This will be followed by an overview of ongoing DT research in optical communications and networking, as well as an outlook on potential future directions for further investigation.