MANET中一种新的路由发现机制

为了避免无线广播风暴，DSR和AODV的洪泛路由发现机制中引入了一种方法RRD（Random Rebroadcast Delay）。然而RRD方法产生了下一跳路由竞争（Next-hopracing）现象，提出了一种基于下一跳节点的位置属性来确定延迟时间（Positional Attribute based Next hop Determination Delay）的方法来解决问题。PANDD方法将根据位置的属性例如相对距离，计算出链路生存期（link lifetime），传输能量消耗，然后一个中间节点将会计算出自己是否适合作为下一跳节点，然后决定相应的重播延迟。相比较RRD方法，采用PANDD方法，使得路由协议在路由优化，端到端传输延迟，能量消耗方面都有显著的提高。

New route discovery mechanism in MANET

The route discovery mechanism in DSR and AODV was introduced the Random Rebroadcast Delay approach in order to avoid the problem of wireless broadcast storm.But RRD approach arose Next-hop racing phenomena.So the paper propose a new Positional Attribute based Next hop Determination Delay(PANDD) approach to address this problem.PANDD base on positional attributes such as the relative distance,estimated link lifetime,transmission power consumption,an intermediate node will identify itself as good or bad candidate for the next-hop node and use different rebroadcast delay accordingly.Compared with RRD approach,using PANDD ap-proach,improve path optimality,and end-to-end delay,reduce transmission power consumption.