Date Added: Sep 2012
Wireless Sensor Networks consist of small nodes with sensing and computation, communication capabilities. Wireless network are highly dependent on specific application and are constrained by energy, storage capacity and power. To increase the lifetime of networks, energy awareness is essential consideration if the authors analyze routing protocols. Routing protocols of sensor networks are responsible for maintaining the routs in the network. In this paper, they analyze recent routing protocols for wireless sensor network and classify in three types of approaches according to network architecture in WSN.