OPEGASIS: Opportunistic Power Efficient GAthering in Sensor Information Systems

Sensor network consists of nodes with limited battery power and these nodes are used in order to collect useful information from the web. Gathering usually required information in an power efficient manner is critical to operate the sensor network for a long period of time. In [4] a data collection problem is defined where a network scenario is defined, each sensor node has a packet to be sent to the distant base station. If all the nodes transmit their data directly to the base station then it will make the system power dissipative. The LEACH protocol presented in [4] is a brilliant solution where clusters are formed to fuse data before transmitting to the base station. By randomizing the cluster heads chosen to transmit to the base station, LEACH achieves a high factor of improvement as compared to direct transmissions, AODV, DSDV as measured in terms of when nodes die. PEGASIS [1], a near optimal chain-based protocol is developed as an improvement over LEACH, in which each node communicates only with a close neighbor and takes turns transmitting to the base station, thus reducing the amount of energy spent per round. But the throughput in PEGASIS can still be increased. This paper provides an improvement to PEGASIS, by introducing OPEGASIS (Opportunistic Power Efficient GAthering in Sensor Information Systems) as by increasing the throughput by communicating the nodes with an opportunistic behavior. Nodes transmit the data to the nearby node as well as far distant nodes in the direction of base station through opportunistic behavior.