Lifetime improvement of LEACH protocol for Wireless Sensor Network

The job of developing a generic protocol framework for Wireless Sensor Networks (WSN) is challenging because, limited processing capabilities, memory and power supply of sensor node make it difficult to cater requirements of versatile applications of these networks. This has forced researchers to dissect the traditional layered protocol design approach. As a result cross layer protocols and architectures that attempt to exploit richer interaction among communication layers to achieve performance gains with limited resources have emerged. From among the cross layer protocols proposed in the literature Low Energy Adaptive Clustering Hierarchy (LEACH), is well referred protocol architecture for WSN. This paper simulates using Network Simulator NS2, analyzes and identifies the shortcomings of LEACH protocol. LEACH does not take into account residual energy and distance of node from the Base Station (BS) for the Cluster Head (CH) selection. We propose Improved-LEACH, in which residual energy and distance of node from BS are used as parameters for CH selection. To save energy, we further propose to start the steady state operation of a node only if the value sensed by a node is greater than the set threshold value. The threshold value will be set by the end user at the application layer. Improved-LEACH is then qualitatively and quantitatively analyzed. The quantitative and qualitative metrics presented for comparison framework can be used to analyze tradeoffs produced by different WSN protocols. They can also be design guidelines for new WSN protocols.