An Efficient Mechanism to Improve Convergecast Traffic in Cluster-tree Wireless Sensor Networks Based on IEEE 802.15.4

The IEEE 802.15.4 and ZigBee applications are widely used specifications for the design of Wireless Sensor Networks (WSNs), Among the different available network topologies, cluster-tree networks are pointed out as the most suitable to implement large-scale WSNs, becoming an attractive solution for monitoring applications. However, cluster-tree networks may suffer from high end-to-end communication delay and also from network congestion. Thus, the selection of efficient network formation schemes and the definition of adequate communication structures are relevant research issues. In this context, this paper proposes an efficient mechanism to improve convergecast traffic in large-scale cluster-tree wireless sensor networks. The main idea combines a network formation process driven by the data generation characteristics of individual nodes and an efficient allocation scheme of the active periods, in order to improve typical convergecast message streams generated by the sensor nodes. Simulation results show that efficient network configuration approaches can significantly reduce end-to-end communication delays and decrease the overall network congestion.