Research On Load Balancing And Bandwidth Control Technology Based On SDN

With the development of large data,cloud computing and other technologies,network traffic shows a geometric growth.The existing network infrastructure has become difficult to meet the needs of business development,which urgently needs efficient and intelligent control of network traffic.However,the traditional IP network is still only based on RIP,OSPF and other routing protocols,which is high complexity and low accuracy.In the peak traffic period,it may lead to link congestion,unreasonable bandwidth allocation and other issues,which have a negative impact on the QoS of users.Therefore,a new network architecture is urgently needed to solve these problems.The emergence of software defined network provides a new way to solve this problem.It is different from the tight coupling of traditional network.It separates control and forwarding from one layer and handles the right of control separately to the controller.Traffic is managed by the way of downstream flow table,which makes the deployment of service faster.In the hierarchical system of SDN,the QoS of users is optimized from two aspects: load balancing and bandwidth control.On the issue of load balancing,the load balancing algorithm based on breadth first search algorithm is applied.This scheme considers both link overhead and transmission distance.In interconnected multiple links,the shortest path can be found accurately and quickly to transmit data.When the data flow increases and congestion occurs,the traffic will be dynamically allocated to another link with the equal hop.Thus,the load balancing under the optimal path is realized,and the data transmission speed is improved.On the optimization of bandwidth control,this paper proposes a bandwidth allocation scheme based on user priority from the point of view of user priority.HTB(Hierarchical Token Bucket)model is used to allocate reasonable bandwidth for users,and queues are created at the bottom virtual switch ports to make traffic by classification.In different queues,the integration and scheduling of traffic are completed when the queue is released,and the accurate allocation of bandwidth is achieved.Finally,the load balancing and bandwidth control schemes for improving user QoS are simulated experimentally,and the experimental results are compared in the SDN environment.The Simulation results show that the proposed scheme can improve network transmission speed,increase network throughput,and can reasonably allocate network resources to achieve the purpose of improving user QoS.