一种基于多SDN控制器的交换机迁移机制

摘要

为了解决SDN(软件定义联网)控制平面的扩展性问题,业界提出了逻辑上集中、物理上分布的多SDN控制器架构,但是该架构中SDN控制器和SDN交换机之间是静态的映射关系,无法动态适应网络中流量的变化,造成了控制器负载不平衡.为了有效解决多SDN控制器部署方案中控制器之间负载不平衡的问题,需要实时监控和共享SDN控制器之间的负载情况,提出一种基于多SDN控制器的交换机动态迁移机制.该机制在控制器失效或控制器负载过大时能够将SDN交换机无缝迁移到其他正常的或负载较轻的控制器,避免了控制器单点失效或者负载过大.实施原型系统基于Floodlight控制器.实验结果表明,该方法能够很好地实现控制器之间的负载均衡,减少控制器对Packet-in消息的响应时间,提高系统的整体性能.%In order to solve the issue of scalability in SDN (Software Defined Networking) control plane,the multiple SDN-controllers architecture with logical centralization and physical distribution is put forward in the industry. However,it cannot dynamically adapt to the change of traffic in the network and causes a load-imbalance among SDN-controllers due to the statically configured mapping between a SDN-controller and a SDN-switch. In order to solve the problem above,the load is needed to be monitoring and sharing between SDN controllers,and a dynamic migration mechanism based on multiple SDN controllers is proposed which can seamlessly migrate a SDN-switch to a normal SDN-controller or that with less load,avoiding the single point faulure or high load of controller during the event of controller failure or overload. A prototype system based on Floodlight is built. Experimental results show that the proposed method a-chieves a better load balancing between controllers,reduces the response time of the Packet-in message,and improves the performance of the whole system.