Minimizing flow initialization latency in Software Defined Networks

Software Defined Networking (SDN) has been a prevalent networking paradigm in recent years. Due to its simplicity to quickly deploy and fully manage networks, both academia and industry are interested in this technology. Nevertheless, there are still many issues to be solved. In this paper, we propose to divide flow table into two separate tables, namely path table and traffic table, to minimize flow initialization latency in SDN. We designed a SDN controller system following this concept and proposed two heuristic algorithms to calculate the two tables. The algorithms take both initialization latency and link utilization into consideration. We implement the proposed system on Ryu controller and perform experiments in a Mininet-based testbed. The experimental results show that our proposed solution outperforms the default spanning tree protocol (STP) application on Ryu controller by reducing: (i) the initialization latency up to 60%, (ii) the maximal link utilization up to 4.78%, and (iii) the average link utilization up to 1.45%.