Node failure is one of the most severe problems that wireless sensor and actuator networks(WSANs) have to deal with. The failure of actuator nodes, in particular, may result in substantial consequences such as network partitioning, incorrect and incomplete decision execution for WSANs. This paper proposes an efficient localized scheme, called LANTR, to repair the damaged topology of inter-actuator network while single actuator node paralyzes. For the failure of an ordinary actuator node, LANTR can rapidly repair the topology through relocating only one-hop neighbors of the failure node, meanwhile, keep the original topology structure as much as possible. Given the magnitude of cut vertex actuators playing on the connectivity, LANTR designs a novel method for each cut vertex to select out a specific guardian node with the minimum degree or minimum cumulative degree from its neighbors, which can reduce the repair influence on the original topology and effectively reduce the coverage loss rate. The performance of the proposed scheme is evaluated and compared with several existing representative topology repair schemes, and the results indicate that LANTR can more effectively and efficiently repair the topology of inter-actuator networks.
在无线传感器网络中,骨干网可方便地实现数据聚合,有利于达到能量高效的数据收集,但是其面临着骨干节点能量消耗过快,易出现因节点能量耗尽而导致骨干网连接中断的问题。为了保证网络能够持续高效的运行,一种基于虚拟骨干网的移动能量补充策略VBMERS(Mobile Energy Replenishment Strategy with Virtual Backbone)被提出来解决网络中骨干节点的能耗过快问题,同时也兼顾对非骨干节点的能量补充。VBMERS策略根据待充电传感器节点当前的通信量计算其优先级,始终选择优先级最大的节点作为充电候选节点以尽量给负载大的节点优先充电,从而避免节点快速进入能量饥饿状态。仿真结果显示,VBMERS策略能有效的解决节点的能量饥饿问题,降低了节点的失效率,进而延长了传感器网络的生存周期。
