Clock synchronization algorithms for networked systems

Abstract

Clock synchronization is a classical topic in the field of networked systems. Real-time industrial Ethernet and wireless sensor networks are two typical kinds of networked systems that have important applications in modern industry. In industrial Ethernet, people usually adopt the IEEE 1588 clock synchronization mechanism, and in wireless sensor networks, people often employ a distributed synchronization algorithm due to limited resources, unreliable communication links, and dynamic network topologies. In recent years, along with the development of a theoretical framework of distributed multi-agent consensus, there are an increasing number of scholars in the control community who are shifting their focus to the distributed clock synchronization algorithm and its applications, and there have been key breakthroughs in the algorithm convergence theorems. Owing to their robustness, flexibility, and ease of implementation, distributed consensus clock synchronization protocols have good prospects; however, many challenging scientific problems remain. In this paper, we summarize the latest research trends on hierarchical and distributed clock synchronization algorithms, especially highlighting the representative clock synchronization algorithms based on consensus control that were proposed in the last five years, and discuss the future directions that aim at providing valuable academic references for researchers working in relevant fields.