A novel tree-based routing protocol in ZigBee wireless networks

In ZigBee networks, ZigBee Tree Routing (ZTR) is the simplest routing protocol with low overhead in which only parent-child links shall be used for packet transfer. However, there exist hop redundancy and traffic concentration in ZTR due to the limitation of tree topology. In this paper, we propose a novel tree-based routing algorithm, which is called Improved Shortcut Tree Routing (ISTR), to decrease hop count and ease congestion in ZigBee networks by using the enhanced beacon frames and extended neighbor tables. ISTR suggests forwarding the packet to the appropriate neighbor node if it can ease network congestion and reduce the routing cost to the destination. The simulation results show that ISTR significantly improves the packet delivery ratio and reduces 20%∼30% of the end-to-end delay compared to ZTR.