Power Aware Differentiated Routing (PADR) in wireless sensor networks

Abstract

Wireless sensor networks are now being used as an effective way of monitoring remote or inhospitable physical environments. But since the nodes in Wireless Sensor Networks are typically very small in size and are powered by irreplaceable battery, one of the major challenge in the design and deployment of such a network lies in the constrained energy and limited computational resource available to sensor nodes. The energy consumption of a sensor node is dominated by the hardware and the communication protocols. This energy depends on whether a sensor node has to perform RT or NRT event detection and traffic forwarding. Therefore wireless sensor network applications must try to resolve the inherent conflict between energy efficient communication and the need to achieve desired quality of service. This report presents a new WSN routing protocol called Power Aware Differentiated Routing (PADR) for routing of RT and NRT traffic in WSN. We modeled PADR Network as RT and NRT Networks superimposed on-top of each other which collaborate to prolong the otherwise shorter RT Network lifetime. We also developed a route selection algorithm that manages swapping of routing responsibilities between RT forwarding nodes and NRT forwarding nodes. In the event that power level of a RT forwarding node falls below minimum threshold value required to perform successful reception and transmission of RT traffic, PADR algorithm ensures that NRT Network nodes provides back-up routing support to the RT network. Results based on the properties of MICA2 radio model show rapid power depletion by RT forwarding nodes as compared to NRT forwarding nodes. Consequently a shorter network lifetime for RT network which forwards more critical data. Results obtained for PADR Network using similar values from the properties of MICA2 shows a remarkable improvement in RT traffic forwarding lifetime under PADR Network deployment.