Research And Design Of Multi-path Load Balancing Scheme Based On SDN

With the rapid development of new internet services(such as social networks,mobile Internet,and Internet of Thing,etc.),the user's demand for bandwidth is getting higher and higher.A important reason why it is difficult for the existing traditional network technology to meet people's demand for diversified bandwidth is that the link bandwidth resources are allocated irrationally.In the traditional networks,the network devices are independent from each other,causing that the link load balancing policies deployed are lack of flexibility and globality.This phenomenon is particularly prominent in large-scale network.SoftWare Defined Networking(SDN),as a new network architecture,changes the shortcomings of traditional network's flexibility and global poor,which brings convenience for impimplementing of global link load balancing.Based on the characteristic of centralized control of SDN technology,this paper proposes a multi-path load balancing scheme,designs and implements this scheme on RYU controller.In order to realize multi-path load balancing scheme,three modules are added on RYU controller: link monitoring module,multi-path module and flow forwarding scheduling module.The main function of the link monitoring module is periodically monitors and counts the network status information,and stores them in a specified data structure.The multi-path module has three function.First,K_SP routing algorithm based on the improved Yen's algorithm is designed.The algorithm calculates the K shortest paths of the source and destination nodes according to the simplified cost of the link.Second,a link evaluation model is designed to score the K paths.Third,The routing information(including the evaluation value,and the bandwidth load balancing determination coefficient)is stored in the specified data structure.The flow forwarding scheduling module selects the optimal forwarding path according to the bandwidth load balancing determination coefficient and the score of the K path,and dynamically formulates the forwarding strategy of the flow.All the experiments in this paper are deployed on the modified Mininet simulation platform,and the iperf command is extended on the Mininet simulation platform to implement a random traffic distribution model for generating real network traffic.The experimental results show that compared with the shortest path routing strategy,the multi-path load balancing scheme can solve the network congestion,improve the average use efficiency of the network link bandwidth,reduce the end-to-end delay,and improve the overall network performance.