An energy efficient and QoS aware multipath routing protocol for wireless sensor networks

Enabling real time applications in Wireless Sensor Networks (WSNs) demands certain delay and bandwidth requirements which pose more challenges in the design of networking protocols. Therefore, enabling such applications in this type of networks requires energy and Quality of Service (QoS) awareness in different layers of the protocol stack. In many of these applications (such as multimedia applications, or real time and mission critical applications), the network traffic is mixed of delay sensitive and reliability demanding data. Hence, QoS routing becomes an important issue. In this paper, we propose an Energy Efficient and QoS aware multipath routing protocol (we name it shortly as EQSR) that maximizes the network lifetime through balancing energy consumption across multiple nodes, uses the concept of service differentiation to allow high important traffic (or delay sensitive traffic) to reach the sink node within an acceptable delay, reduces the end to end delay through spreading out the traffic across multiple paths, and increases the throughput through introducing data redundancy. EQSR uses the residual energy, node available buffer size, and Signal-to-Noise Ratio (SNR) to predict the best next hop through the paths construction phase. Based on the concept of service differentiation the EQSR protocol employs a queuing model to handle both real time and non-real time traffic. By means of computer simulations, we evaluated and studied the performance of our routing protocol and compared it with another protocol. Simulation results have shown that our protocol achieves lower average delay and higher packet delivery ratio than the other protocol.