Scalable network joining mechanism in wireless sensor networks

It is of great concern to employ an efficient network joining mechanism to construct a large scale wireless sensor network (WSN). For example, ZigBee can construct a cluster-tree based WSN with the use of a simple network joining, addressing and routing mechanism. However, when applied to a large scale WSN, it may not provide desirable node connectivity mainly due to the waste of network depth and networking bias. In this paper, we consider the design of network joining algorithms that can construct a large scale cluster-tree structured WSN with maximal node connectivity. A new node willing to join as a router selects its parent node among neighbor routers which are closer to the network coordinator than itself, reducing the waste of network depth. The parent node selects isolated nodes first as its child routers, alleviating the networking bias problem. Finally, the performance of the proposed networking mechanism is verified by computer simulation, showing remarkable performance improvement over conventional ZigBee in a large scale WSN¹.