Power Aware Differentiated Routing (PADR) in Wireless Sensor Networks

We analyze routing algorithm for wireless sensor networks called power aware differentiated routing (PADR), which is proposed for collaborative routing of real-time (RT) and non-real time (NRT) traffic in a sensor field in order to prolong the otherwise shorter life time of RT sensor network. PADR uses nodes in the non-real time network as backup for routing RT traffic. It involves swapping a forwarding node for RT traffic from a node with critical minimum power level to the node with the best power level (often from a node in RT network to a node in NRT network). We derive analytical expressions for life time of RT and NRT networks under PADR routing protocol. The numerical results show that the performance of PADR depends on the remaining power of sensor nodes during route swapping. The results also show that PADR can increase the life time of RT network by up to 50%, and that similar reduction level of life time is incurred to NRT network.