Research And Implementation Of SDN Failure Monitoring And Recovery Technology

With the continuous development of social economy,Software Defined Networking(SDN),as new network architecture,has been attracting people's attention.SDN has a high degree of network abstraction,novel centralized intelligence and good programmability.However,SDN network can not yet avoid network failure phenomenon occurred in the traditional network.The crash or failure of the SDN controller,as the control and management center of the whole network,can easily lead toservice disruption and other adverse effects in the whole network.Therefore,it is of great practical value to study failure monitoring and failure recovery technology of the SDN network.This thesis analyzes the SDN network architecture,studies the workflow of the controller and SDN switch,clarifies the security factors threating the SDN network,summarizes the SDN network failure range and determines the failure type.Combined with the OpenFlow message type,from the SDN network data plane and the control plane two angles,it summed up the failure monitoring method for different types of failures.Analyzing the advantages and disadvantages of two methods,namely data plane active mode and passive mode.A failure recovery method for multiple logical SDN controllers combined with the active and passive modes is proposed.This thesis analyzes the requirements of multi-controller system and OpenFlow protocol for multi-controller.Based on the active and standby controller model,the failure recovery method for multiple logical SDN controllers is realized.This thesis uses Big Switch Networks' core enterprise-level Floodlight controller and OpenvSwitch software switch,combines with Wireshark and Iperf test tools and uses the physical test equipment and simulation software Mininet to test and verify SDN network failure monitoring and recovery.Test results show that the relevant functional modules can realize the functions of monitoring and recovering these failures.