摘要
针对SDN多控制器负载均衡过程中,控制器选取僵化和交换机迁移冲突问题,提出了一种基于分布式决策的控制器负载均衡机制,分为三个阶段进行实施:首先通过周期性收集网络信息,结合控制器负载状况构建分布式迁移决策域;然后在域中依据选取概率确定迁移交换机,综合权衡数据收集、交换机迁移和状态同步三种代价选择目标控制器;最后建立迁移时钟模型,完成交换机迁移和控制器角色转换.仿真结果表明,与现有的负载均衡机制相比,降低了网络的通信开销,流建立时间平均缩短0. 14s,控制器资源利用率提高了21. 7%.
In the process of SDN multi-controller load balancing,controller selecting is rigid and switch migration is conflicting. This paper proposes a controller load balancing mechanism based on distributed policy,which is divided into three phases. Firstly,through collecting network information periodically,distributed migration decision domains are structured according to controller load conditions. Then the switches are migrated according to selecting probability. By balancing three costs included data collection,switch migration and state synchronization,the target controllers are determined. Finally,this mechanism sets the migration countdown to complete the switch migration and controller role conversion. Results showthat,compared with the existing load balancing mechanism,this method could reduce the total network communication overhead,flowestablishment time is shortened 0. 14 s averagely,controller resource utilization has been increased by 21. 7%.
引文
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