Design Of A High-availability SDN Architecture And Its Key Technology Research

Software defined networking(SDN),as one of the key research trends of future networks,which have the separation of forwarding and control,and the virtualization features are gaining in popularity.Through centralized control,SDN can quickly achieve business deployment and make the whole network resources be used more efficiency.Although centralized control features bring about numerous advantages such as controllability,safety and rationality,etc.But with the continuous expansion of business scale and complexity of the applications,it also generates the issues of scalability and reliability.In this thesis we present a high-availability SDN architecture based on previous studies,and mostly focused on the heartbeat mechanism of control plane and virtual network mapping algorithm of data plane.Firstly,we design a high-availability SDN architecture of control plane,Which contains three modules that are Controller Cluster,Heterogeneous Redundant Heartbeat Detection and Shared Database.Secondly through the study of the controller cluster,we present an adaptive heartbeat timeout algorithm to detect the controller failure.Simulation results show that this mechanism can quickly detect failures and improve detection accuracy.Furthermore,this thesis also does researches on high-availability virtual network mapping of SDN.Firstly,a network topology pre-optimizing mechanism is proposed based on the index of node and link failure rate and failure recovery time.Secondly,we propose a high-availability mapping algorithm based on resource utilization.Simulation results show that this algorithm can effectively balance the resource utilization of each node,avoiding frequently mapping which is a heavy burden for nodes.Simulation and analysis demonstrate that the proposed method can effectively ensure high availability of virtual networks.