A wireless sensor network is a computer network that consists of small devices called sensor nodes. These sensor nodes have the ability to sense different environmental conditions like temperature, pressure, etc. All these sensor nodes send their data to a central node or base station. This creates a large communication overhead the energy source for these nodes is usually a battery. This gives rise to huge consumption of energy and resources. So a solution is required that overcomes the above problems. Data aggregation is one of its solutions. This method consists of aggregators that combine the data coming from the sensor nodes and then passes it to the base station. With the help of data aggregation we reduce the energy consumption by eliminating redundancy and we can enhance the life time of wireless network. The purpose of the proposed paper is to explain data aggregation in wireless sensor network, how it works, different techniques of data aggregation and the comparison among them.
Wireless Sensor Network, Energy Consumption, data aggregation
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