Performance Assessments for SDN Control Plane into Distinct Network Topologies

The Software Defined Network (SDN) concept has changed the traditional network architecture to achieve higher flexibility, the programmability of the network, the abstraction based on a logically centralized control plane, and the data (forwarding) plane decoupling. The SDN control centralization raises scalability issues. This work focuses on the scalability concerns of the Ryu SDN controller in various scenarios with distinct network topologies like tree and datacenter. Throughout this paper, we assess the consequences of distributing subscriber data requests over the controller performance into different network topologies also using a different number of subscribers. The performance of the Ryu is tested by observing the throughput of the controller. The assessment was accomplished by employing an Iperf traffic generator and Mininet. The paper studies two matters that impact the Ryu throughput: the exponential increase of the number of nodes in tree topology and the adoption of the same condition over a datacenter topology. The experiments involve the two types of topologies mentioned and a topologies size range from 200 to 2000 nodes and assessing the controller performance using the throughput as the performance criterion. The results of this research will be used in a research project oriented to 5G slicing, where the control plane is based on SDN.