【摘要】 在无线AdHoc网络中,由于节点的频繁移动导致的路由失效引起了网络性能的严重下降。文中提出了一种针对无线AdHoc网络按需路由协议的抢先式路由算法。该算法以链路状态分析为基础,在路由发现时尽量保证新发现路由的可靠性;若节点接收信号强度小于危险阈值,则启动链路状态分析模块预测链路失效时间,如果预测结果小于反应时间,就提前进行路由维护。仿真结果表明,该算法能以可接受的开销有效地减少路由失效数、降低分组投递延迟,提高了网络性能。更多还原

【Abstract】 Mobility of the nodes in wireless ad hoc networks causes routes to break frequently, which results in significant performance degradation of networks. An extension to ondemand ad hoc routing protocols called Preemptive Routing Algorithm is proposed in this paper. Link State Analysis is the essential part of the algorithm. The preemptive algorithm tries to ensure the reliability of the new discovered route during the route discovery. When the received signal power is below the dangerous threshold, Link State Analysis module is initiated to predict the broken time of the link. A preemptive route maintenance action is taken in advance if the predicted broken time is less than response time. The simulation result shows that Preemptive Routing Algorithm proposed in this paper significantly reduces the number of broken paths, decreases the packet delivery delay and improves the performance of networks with a small increase of protocol overhead.更多还原