A novel formation scheme for IEEE 802.15.4 WSN

This paper proposes a novel formation scheme for an IEEE 802.15.4 wireless sensor network which is organised into a tree topology. This scheme consists of the network formation initialisation algorithm and the network formation maintenance algorithm. In the initialisation algorithm, each node first calculate the lengths of routing paths reaching all other nodes in the network, and then the node with the minimum path length is elected as a root. In this way, the average length of the routing paths is reduced and accordingly the routing delay is also shortened. After the initialisation algorithm is executed, the maintenance algorithm is performed to maintain the tree topology. When the tree topology changes, the maintenance algorithm can dynamically adjust the root in order to reduce the average length of the routing paths and shorten the routing delay. This scheme employs beacons to achieve the initialisation algorithm and the maintenance algorithm, so the extra costs and delays are avoided. This scheme is analysed and evaluated, and the data results show that this scheme effectively reduces the average length of the routing paths and shortens the routing delay.