Research On Routing Protection Scheme Based On Software Defined Network

With the rapid growth of network traffic,network failures are inevitable.Route protection schemes are commonly adopted in academia to deal with network failures.The existing routing protection scheme has two problems: on the one hand,the failure protection rate is low;On the other hand,when the network fails,routing loops can occur in the backup path.The emergence of Software Defined Network(SDN)provides new ideas for solving the above problems,but the widespread deployment of SDN equipment with existing technology is costly and will cause network outages,so it is impossible to upgrade all traditional devices to SDN devices in the short term,and the development of future network architecture will inevitably follow the "traditional network structure-hybrid SDN network structure-SDN network structure where traditional devices and SDN devices coexist This model.Based on this,this paper mainly studies the hybrid SDN network structure and the routing protection scheme in the SDN network structure,as follows:.For the single-node failures that may occur in hybrid SDN networks,two heuristic algorithms,GARPHSDN(Greedy Algorithm for Routing Protection based on Hybrid Software Defined Networks)and IPGARPHSDN(Improved Greedy Algorithm for Routing Protection based on Hybrid Software Defined Networks,IPGARPHSDN),are proposed in this paper,and their failure protection rates,the number of SDN nodes to deploy,and The time overhead and complexity are discussed in detail.Finally,the two algorithms are compared through simulation experiments.The results show that only a few devices in the traditional network need to be upgraded to SDN devices,and both algorithms can achieve100% failure protection rate.At the same time,the time overhead of IPGARPHSDN algorithm is much less than that of GARPHSDN algorithm,which is more suitable for actual deployment..To solve the problem of low routing availability in SDN network structure,this paper presents an RPAHFPR(Routing Protection Algorithm with High Failure Protection Ratio)algorithm,which combines the path generation algorithm,bypass priority algorithm and loop evasion algorithm,and can solve the problem of low failure protection rate and routing loops faced by existing routing protection schemes at the same time.Finally,the performance of RPAHFPR algorithm is validated in a large number of real and analog network topologies.Compared with classical NPC and U-TURN algorithms,the fault protection rate of RPAHFPR algorithm is increased by 20.85% and 11.88%,respectively,and it can reach 100% fault protection rate in 86.3% of topologies,and more than 99% in all topologies.The path stretch of RPAHFPR is close to 1,which does not introduce too much time delay.