Research Of The Failure Detection And Recovery Based On SDN

As the computer network architecture is becoming more and more complex and increasing types of businesses need to be supported,the traditional Internet architecture based on TCP/IP is more and more powerless.Depending on the advantages of SDN(Software Defined Networking),this thesis introduces SDN architecture into the strategy design of network failure detection and recovery to solve problems that businesses are interrupted and the bandwidth requirement cannot be satisfied during link failure in the traditional network,and improve the reliability of the network.Based on the research of network failure detection and recovery techniques home and abroad in recent years,this thesis compares the advantages of existing achievements and disadvantages of different methods,and proposes a kind of failure detection and recovery method based on SDN.Aiming at the slow response to the link failure in the traditional network architecture currently,this thesis firstly combines the fast failover of the Open Flow group tables and BFD(Bidirectional Forwarding Detection)based on existing research achievements to detect the operation status of current links.Secondly,this thesis divides the whole network into multiple domains,calculates all loops in the network using UGLA(Undirected Graph Loop Algorithm),and centrally manages these domains by MPLS(Multi-Protocol Label Switching)tags to save storage resources for switches and improve the efficiency of matching flow tables.Finally,this thesis proposes a kind of link evaluation method to ensure that businesses can operate normally and smoothly during network failure.This link evaluation method selects the optimal path between two domains to forward the data traffic using UGLA algorithm,thus meets the bandwidth requirement and guarantees the quality of service.On the basis of the above methods,this thesis designs and implements the failure detection and recovery system based on SDN in the Floodlight controller,and verifies the functions and performance of the system in the network environment build by Open v Switch.The experiment results indicate that the failure detection and recovery system based on SDN can monitor the operation status of links in the network in real-timely.If one or more links are broken,the system can quickly detect the failure and restore the service to avoid interruption of the communication,and also satisfy the transmission bandwidth need of businesses to improve the efficiency of network management and the reliability of the network.