Research On Rerouting Strategy For SDN Link Failure

With the rapid development of information technology in recent years,the relatively static traditional network architecture can’t meet the ever-increasing demand for dynamic services.The complex structure of the traditional vertical integration of the network is isolated from each other,and it is impossible to abstractly solve the common problems of the emerging business of the network.The service mechanism of "delivering with the best effort" is gradually unable to meet the needs of dynamic business.Software Defined Networking(SDN),as a new network architecture,decouples the control plane and data plane,showing the possibility of efficiently processing dynamic network services.This paper introduces the SDN network architecture into the link failure rerouting strategy,which aims to solve the problems of service transmission interruption and low bandwidth utilization caused by link failures in networks,so as to ensure the quality of data transmission and improve network performance.This paper investigates and analyzes the current research work done on link failure rerouting at home and abroad,compares the existing results and existing problems,and proposes a rerouting strategy for SDN link failures.First,to solve the problem of limited memory resources of SDN switches,the Topological Loop Partition Algorithm(TLPA)is designed based on the greedy strategy to decompose the SDN network logic to generate multiple basic logic forwarding units,and use MPLS labels to forward the logic.Units are managed uniformly,which simplifies the network topology and reduces the resource requirements for flow entries.Then,in view of the bandwidth usage of the rerouting path,the rerouting path evaluation algorithm is combined with the SDN controller to quantitatively evaluate the attributes of each link in the network topology,and select the rerouting path according to the real-time state of the network,which improves the link bandwidth utilization,avoiding data congestion.Based on the above strategy modeling research and system prototype design,this paper implements an SDN rerouting path selection system,and tests the system functions in a virtual network environment built by Mininet simulation software.The test results show that the SDN rerouting path selection system can quickly select the rerouting path and restore data communication when the link fails.Compared with the flow table strategy of the active scheme and the controller strategy of the reactive scheme,it reduces the resource requirements of flow table entries,improves link bandwidth utilization,and guarantees the quality of data transmission.