Date Added: Mar 2012
A sensor in Wireless Sensor Networks (WSNs) periodically produces data as it monitors its vicinity. The basic operation in such a network is the systematic gathering (with or without in-network aggregation) and transmitting of sensed data to a base station for further processing. A key challenging question in WSNs is to choose best routing protocol to gather data from various sensing devices and send it to the base station (sink). Routing protocols used in various networks (homogeneous, heterogeneous and hybrid) are the same. Routing protocol which consumes less energy and produces minimum traffic is used in that particular network. This paper gives a survey of different routing protocol and a way to save energy used for data aggregation in sensor network.