A hybrid routing protocol for wireless sensor networks

The ZigBee standard which has been widely adopted for wireless sensor networks specifies two routing protocols. One is a path search protocol which finds the best path by flooding whole or part of the network with path search messages costing significant amount of energy and bandwidth. The other is a simple tree routing protocol which eliminates path search by solely following the parent-child links and, therefore, conserves energy and bandwidth but generates inferior routes. We propose a hybrid routing protocol which improves the efficiency of tree routing with minimum additional storage and computational cost. Particularly, in addition to the parent-child links, the proposed protocol also uses links to other one-hop neighbors if they are identified to be able to provide a route shorter than the tree path. The address assignment scheme of ZigBee networks is exploited to make such identification possible. Simulation results confirm the performance of the proposed protocol.