A Fuzzy Logic-Based Framework for Multi-Objective Controller Placement in Software Defined Networks

Software Defined Networking (SDN) has been hailed as a revolutionary development in network management, with the potential to transform the landscape of the industry. The core principle behind SDN is the decoupling of the control plane from the data plane, a move that has been widely regarded as a significant step towards more centralized control. Nevertheless, determining the optimal placement of controllers, known as the Controller Placement Problem (CPP), remains a significant challenge due to conflicting objectives such as latency, resilience, and load balancing. This paper proposes a novel approach leveraging fuzzy logic to address the CPP. Distinct from heuristic or optimization algorithms, this approach employs fuzzy set theory to manage imprecise and dynamic network parameters while optimising multiple objectives, including latency, inter-controller communication, and load balancing. The proposed method provides a flexible, adaptable framework for CPP across varying network topologies. Experimental results validate the effectiveness of this approach in achieving balanced trade-offs among objectives, ensuring efficient and scalable SDN management, with a 18.7% reduction in maximum node-to-controller latency and a 22% improvement in load imbalance compared to state-of-the-art methods.