Research On SDN-CDC Egress-Routers Load Balancing Strategy

Currently,due to the limitations in the architectural design of traditional network-based cloud data centers,it is impossible to globally control the network devices,not to mention the dynamic scheduling of network traffic,which leads to the degradation of network service quality.And the emergence of software-defined networking provides a new idea and direction to solve the load balancing problem of cloud data center.Therefore,this thesis investigates cloud data centers based on software-defined network architecture,focusing on load balancing among egress routers in cloud data centers,and proposes the SCELB strategy.The strategy aims to achieve load balancing among egress routers and improve the quality of network services in cloud data centers by optimizing packet forwarding scheduling at the egress router end.The main work of this thesis is as follows.(1)This thesis treats the cloud data center as a black box,ignores the packet forwarding process inside the link,focuses on the load situation and packet forwarding situation of each egress router,and proposes a load balancing policy SCELB among egress routers based on the software-defined network cloud data center to realize the load balancing of the software-defined network cloud data center.(2)This thesis divides the SCELB policy into two parts of LBPTM mechanism and RTSM mechanism for policy design,and then deploys the SCELB policy modularly with five modules,including network-aware module,load balancing monitoring module,LBPTM trigger module,RTSM module,and policy deployment module.(3)The feasibility of the SCELB strategy proposed in this thesis is verified through the feasibility verification experiments designed based on Matlab,and finally the performance test experiments are conducted on the strategy using the Mininet simulation platform.By analyzing the experimental results,it can be seen that,in the regular performance test experiments,for the average delay,the SCELB strategy reduces 6.2% and 15.8%,respectively,compared with ECMP and Dijkstra strategy;for the average packet loss rate,the SCELB strategy reduces 7.3% and 11.2%,respectively,compared with ECMP and Dijkstra strategy;for the average link utilization,the SCELB policy improves 8% and 14.8% compared with ECMP and Dijkstra policy,respectively.In the simulated user access experiments,for the average delay,the SCELB policy reduces 9.7% and 15.1% compared to ECMP and Dijkstra policies,respectively;for the average packet loss rate,the SCELB policy reduces 7.8% and14.5% compared to ECMP and Dijkstra policies,respectively;for the average link utilization,the SCELB policy improves the average link utilization compared to ECMP and Dijkstra policies,respectively.and Dijkstra strategy by 7.2% and 14.5%,respectively.Therefore,it is concluded that the load balancing performance of the SCELB policy is better than that of the ECMP and Dijkstra policies.