Optimising SDN throughput via flow-table management: a comparative study and future research outlook

Software-Defined Networking (SDN) has transformed how networks are managed by separating control from data plane, making them more flexible and programmable However, throughput performance remains constrained by controller latency and the limited size of ternary content-addressable memory (TCAM) in switches. To tackle this, Flow-Table Reduction Schemes (FTRS) offer a simple, software-driven fix. In this paper, we explore how SDN throughput optimization has evolved, compare popular controllers, and show where FTRS fits in. We share real-world results from implementing FTRS on the Ryu controller, discuss why these matters for cost and sustainability, and outline future directions like using machine learning and multi-controller setups for smarter, faster networks

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