Link and Location Based Routing Mechanism for Energy Efficiency in   Wireless Sensor Networks
  In Wireless Sensor Networks, sensed data are reported to the sink by the available nodes in the communication range. The sensed data should be reported to the sink with the frequency expected by the sink. In order to have a communication between source and sink, Link based routing is used. Link based routing aims to achieve an energy efficient and reliable routing path. This mechanism considers the status (current energy level in terms of Joules) of each node, link condition (number of transmissions that the Cluster Head (CH)and the Gateway (GW) candidates conducts) and the transmit power (power required for transmission in terms of Joules). A metric called Predicted Transmission Count (PTX) for each node is calculated using its status, link condition and transmit power. The node which has highest PTX will have the highest priority and it will be the potential candidate to act as CH or GW. Thus the selection of proper CH or GW reduces the energy consumption, and the network lifetime is increased. 
G. Pavithra and P. Devaki
cs.NI