Improving Robustness and Reducing Control Overhead via Dynamic Clustering in Tactical SDN

This study presents a dynamic clustering approach to address the challenges of managing modern and dynamic tactical communication using diverse radio links in Software-Defined Tactical Networks (SDTNs). State-of-the-art conventional Software-Defined Networking (SDN) protocols, which rely on centralized controllers, are unsuitable for tactical scenarios due to their inherent demands for high-throughput, low-latency control planes, and static nodes. To enable SDTN, we propose a clustering solution designed to distribute network nodes across multiple remote controllers, thereby reducing the control message overhead created by the OpenFlow protocol. Moreover, we propose a flexible controller assignment strategy to dynamically balance the network load during runtime and improve network robustness using backup controllers. Our comparative analysis suggests a significant reduction of control overhead across heterogeneous topologies with VHF and UHF links using our clustering solution. Furthermore, we replicate a real-world scenario by emulating a convoy of military vehicles demonstrating the effective distribution of low control overhead among the controllers and maintaining robust network connectivity, even in the event of a controller failure.