摘要
Energy efficiency and network lifetime are main concerns in WSN. In order to improve these factors ZigBee plays an important role. Low cost, low data rate features of ZigBee results in low power consumption and makes it useful in wireless sensor networks, increasing life of small batteries of nodes in the network. Since tree routing in ZigBee does not require any routing tables to send the packet to the destination, it can be used in ZigBee end devices that have limited resources. Routing protocols such as AODV (Ad-hoc on demand distance vector routing), ZTR (ZigBee tree routing), and STR (Shortcut tree routing) are compared on the basis of different performance metrics (End to end delay, routing overload, throughput, packet delivery ratio). An extensive simulation in NS2 is carried out. The performance evaluation shows that STR achieves better performance as compared to other two routing protocols. But there are some limitations of the STR method. Performance of packet delivery ratio of STR is less as compared to AODV. Performance of end to end delay of STR is poor as compared to AODV. Hence ESTR is proposed. The main aim of proposed ESTR [Extended STR] is to present new ZigBee network routing protocol with goal of improving the performance of ESTR in terms of PDR and delay against STR and AODV.