Pervasive Systems Research Group, Department of Computer Science, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.
Sensors (Basel). 2011;11(12):11415-46. doi: 10.3390/s111211415. Epub 2011 Dec 1.
In order to efficiently deal with location dependent messages in multi-sink wireless sensor networks (WSNs), it is key that the network informs sinks what geographical area is covered by which sink. The sinks are then able to efficiently route messages which are only valid in particular regions of the deployment. In our previous work (see the 5th and 6th cited documents), we proposed a combined coverage area reporting and geographical routing protocol for location dependent messages, for example, queries that are injected by sinks. In this paper, we study the case where we have static sinks and mobile sensor nodes in the network. To provide up-to-date coverage areas to sinks, we focus on handling node mobility in the network. We discuss what is a better method for updating the routing structure (i.e., routing trees and coverage areas) to handle mobility efficiently: periodic global updates initiated from sinks or local updates triggered by mobile sensors. Simulation results show that local updating perform very well in terms of query delivery ratio. Local updating has a better scalability to increasing network size. It is also more energy efficient than our previously proposed approach, where global updating in networks have medium mobility rate and speed.
为了有效地处理多Sink 无线传感器网络（WSNs）中与位置相关的消息，网络告知 Sink 哪些地理区域由哪个 Sink 覆盖是关键。然后，Sink 能够有效地路由仅在部署的特定区域内有效的消息。在我们之前的工作中（请参阅第 5 项和第 6 项引用的文档），我们为与位置相关的消息（例如，由 Sink 注入的查询）提出了一种组合的覆盖区域报告和地理路由协议。在本文中，我们研究了网络中存在静态 Sink 和移动传感器节点的情况。为了向 Sink 提供最新的覆盖区域，我们专注于处理网络中的节点移动性。我们讨论了更有效地处理移动性的更新路由结构（即路由树和覆盖区域）的更好方法：由 Sink 发起的周期性全局更新或由移动传感器触发的本地更新。仿真结果表明，本地更新在查询交付率方面表现非常出色。本地更新对于增加网络规模具有更好的可扩展性。与我们之前提出的方法相比，它也更节能，其中网络中的全局更新具有中等的移动速度和速率。
