软件定义网络容错控制平面的最小覆盖布局方法

Minimal Coverage Model for Fault-Tolerant Controller Placement in Software Defined Networks

容错控制平面通过将多个控制器部署在不同的网络设备上进而增强网络的可靠性,但是大量的控制器部署带来了巨大的布局成本,严重地限制了容错控制平面在实际网络中的部署与应用。为了解决上述问题,该文首先构造了容错控制平面的最小覆盖布局模型,然后设计了一种基于局部搜索策略的启发式控制器布局算法,避免搜索结果陷入局部最优解。在不同规模网络中的仿真结果表明,相对于其他算法,所提算法可以在保证网络容错需求的同时,降低网络中部署控制器的数量。

In order to deploy fault-tolerant Software-Defined Networks(SDN),many controllers must be physically distributed among different network devices.However,a large number of controllers bring huge costs,which limits severely the application of the fault-tolerant control plane to the real networks.In order to solve the above problems,the fault-tolerant control plane is analyzed and a mathematical model that covers all switches using the least number of controllers is constructed.Then,a heuristic controller placement algorithm based on the local search strategy is proposed to avoid the local optimal solution.The experimental results show that compared with other algorithms,the proposed algorithm can effectively reduce the number of required controllers while ensuring network fault tolerance requirements in different scale networks.