Wireless sensors nodes are made up of small electronic devices which are capable of sensing, computing and transmitting data from harsh physical environments like a surveillance field. These sensor nodes majorly depend on batteries for energy, which get depleted at a faster rate because of the computation and communication operations they have to perform. Communication protocols can be designed to make efficient utilization of energy resources of a sensor node and to obtain real time functionality. In this paper, two classic energy-efficient protocols LEACH (low-Energy Adaptive Clustering Hierarchy) and PEGASIS (Power-Efficient Gathering in Sensor Information Systems) are analyzed, compared and discussed. LEACH introduces clustering based protocol, where sensor nodes are grouped in several clusters and have randomized rotation of cluster-heads that will transmit a data to Base Station (BS). PEGASIS is a chain-based protocol built on top of idea from LEACH, which nodes communicate only to its neighbor and takes turn to be leader to send data back to the BS. We evaluate the performances of these protocols by using C++ programming language.

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Leach Pegasis Hierarchical Clustering Sensor Nodes Wireless Sensor Network