ONOS-Based Hierarchical Multi-Domain High-Performance Control System

SDN is a novel paradigm for future networking which seperate control plane from datapane.The dataplane is responsible for data forwarding while the logical centralized control plane handles the network events according to network view and status,which provides a feasible network management mechanism.In the early days of SDN,when the size of network was limited,the performance of the control plane was enough to meet the control requirements of the network.However,as the scale of deployment of SDN networks continues to expand,the centralized control plane becomes a bottleneck that restricts the expansion of the SDN network.In this this thesis,the SDN scalability problems are studied in depth.The main contributions of this thesis are as follows:(1)With the study to main multi-controller scalability control plane solutions,a hierarchical multi-domain high-performance control system is designed and implemented based on the open source controller ONOS using the highly scalable hierarchical multi-controller architecture.The system separates the control plane and partition the network,which can effectively reduce the communication overhead of the control plane and improve the scalability of the SDN network.The experiment results verify the availability and efficiency of the system.(2)In order to solve the problem of controller deployment in hierarchical control architecture and to find the optimal controller deployment strategy,aiming at minimizing the average delay of switch requests,a controller deployment algorithm based on clustering and genetic algorithm is proposed.The algorithm can solve the optimal controller deployment strategy for a limited time,including the location of the controller and the network area under control.Comparison of simulation results show that the proposed controller deployment algorithm can effectively reduce the average request delay of switches and can be used to optimize the deployment of controller resources.(3)To meet the deployment requirement of large-scale network control plane,a control plane in-band networking scheme is proposed,which enables the control plane of the hierarchical multi-domain control system to be deployed in and shares data plane network when no dedicated control plane network is provided.The experimental results verify the availability of the in-band networking scheme.This scheme can be applied to the hierarchical multi-domain control plane of large-scale SDN networks where no dedicated control plane network is provided.