A Congestion-Aware Routing Protocol for Voluminous Data Collection in Wireless Sensor Networks

In an event-based Wireless Sensor Network (WSN), a sensor node generates data on occurrence of an event. The generated data packets may be voluminous and the data need to be delivered at the destination with minimal delay for applications like intrusion detection in the battle-field, monitoring chemical plants, nuclear plants, health of bridges and issuing tsunami alerts. Wireless sensor networks are limited in resources, such as energy, storage, processing power and bandwidth. A huge amount of data and limited bandwidth may result in packet collisions, which leads to packet drops. To achieve the data transmission reliability, retransmission of the lost packets need to be done. However, retransmissions increase packet delivery delay and energy consumption. In this paper, a data forwarding (routing) mechanism has been proposed to control the congestion for voluminous data collection in Wireless Sensor Networks. Further, a M/M/1/B queueing model has been adopted to determine the probability of occurrence of buffer overflow at a node. In the proposed mechanism, every node chooses the best node to route the data based on the level of congestion and available buffer space at upstream neighbour nodes. Simulation has been performed and results are compared with AODV (ad hoc on-demand distance vector) routing algorithm to show the virtue of the proposed mechanism in terms of packet drop, average packet delay and packet delivery ratio.