Wireless Sensor Network (WSN) refers to a group of spatially dispersed and dedicated sensors for monitoring and recording the physical conditions of the environment. A sink node (gateway) collects data from sensors through single or multi-hop communication and processes it by ensuring that end-user can access data. In WSN applications sensor nodes having limited batteries are deployed. Hence sensors lifetime is strongly restricted by the battery lifetime. So managing energy consumption is big challenge to WSN. In this paper, the author has considered various approaches for extending network Lifetime. These approaches are duty cycling, topology control, clustering, controlled mobility and mobile node rotation. Mobile node rotation approach is best overall approaches for extending network lifetime.