基于链路权重的SDN组播链路恢复机制

Link recovery mechanism of software-defined-network multicast based on link weight

基于软件定义网络(SDN)的组播树在数据传输时,若链路出现故障,交换机需通过备份路径或通知控制器更新流表以恢复传输。但现有方法主要考虑减少恢复延迟和丢包,忽略流表项的资源消耗问题。因此,为尽可能平衡备份表项的资源开销和恢复路径的时间开销,提出基于链路权重的SDN组播链路故障恢复机制。针对两类不同链路提供相应的恢复策略,在保证可靠传输的基础上,考虑采用较少的备份流表项解决链路故障,恢复组播树数据的接收。仿真结果表明,该方案在备份流表项占比和路径恢复时间上有明显优势,在保证时延要求的同时,减少了资源消耗。

In the process of data transmission of multicast tree based on Software Defined Network(SDN),if the link fails,the switch should update the flow table through the backup path or inform the controller to repair the fault.However,the existing methods mainly consider reducing the recovery delay and packet loss and ignore the resource consumption of flow table entries.Therefore,in order to balance the resource cost of backup table entries and the time cost of recovery path as much as possible,a link weight-based SDN multicast link fault recovery mechanism is proposed.The corresponding recovery strategy is provided for the two types of different links.On the basis of ensuring reliable transmission,it is considered to adopt fewer backup flow table items to resolve link failures and restore the reception of multicast tree data.The simulation results show that this scheme has obvious advantages in terms of the proportion of backup flow table entries and path recovery time,and reduces the resource consumption while ensuring the requirement of delay.