Online Monitoring Performance For Sdn Controller

Software Defined Networking(SDN) is a new type networking paradigm, which separates control and forwarding, centralize logical control and provides programmable interfaces for applications. It promises to dramatically simplify network management, to reduce network operation cost and promote network innovation, however with network scale and traffic growing up, performance of SDN controller can probably be bottleneck because of it centralize logical control. Nowadays, most research on controller performance is just benchmarking its performance in simple scenarios, lacking controller performance monitor research based on complex scenarios. Besides, most of studies use average response delay to measure controller latency performance; however, it can’t reflect the distribution of response delay and may not characterize latency performance exactly.In order to still obtain controller exact latency performance status in variety of complex scenarios, a universal controller performance metrics index and a scalable controller performance online monitor system framework are designed. The metrics monitors controller performance information directly in controller; therefore it can be applied for different network scenarios. The metrics can reflect controller performance exactly for it is computed in the aspect of statistical distribution and user experience. The online monitor is acted as a function module in controller; it can be applied for variety controllers. The framework, acting as an online monitor module, can reflect the state of controller performance online by monitor designed performance metrics.According to the prototype of online performance monitor implemented in a common controller, feasibilities of designed controller performance metrics and online monitor system are verified. Meanwhile, the controller performance status variation cases are discussed when controller is on dynamic workload, with different threads and on different network scales. It is of great significance to exactly monitor controller real-time latency performance status online for feedback control improving controller performance and diagnosis controller performance problems.