An Energy-Efficient Hybrid Routing Method for Wireless Sensor Networks with Mobile Sink

In wireless sensor networks (WSN), nodes usually use multi-hop communication to transmit sensed data to the base station. Consequently, sensors near the sink deplete their energy quickly and the sink will be isolated from the network. Moving the sink all around the network can alleviate this problem. Yet, sink mobility causes some challenging issues in WSNs which makes it almost impossible to use the classic routing protocols of WSNs with static sink. Therefore, it is required to develop new routing protocols or extend the existing ones. This paper presents an energy-efficient hybrid routing method for WSNs with mobile sink that combines proactive and reactive schemes. Our model is also applicable to the battlefield with a vehicle as the mobile sink. The primary objective of the proposed method is to increase the lifetime of sensor networks by reducing control messages and average hop counts, different traffic patterns flexibility and the protocol usability for most applications. The proposed method suggests several new algorithms to fulfill its purposes. Simulation results confirm that the proposed method extends the network lifetime from 5 to 9 % compared to the existing techniques. A distinguishing attribute of this method is the decreased amount of control message overhead compared with similar approaches.