Efficient load sharing routing algorithm to increase lifetime of Wireless Sensor Networks

Wireless Sensor Networks (WSN) are low power networks which have many small nodes. The nodes are low power sensors interconnected to each other to receive and transmit data from source to sink. By the transferring of data, the power of these nodes reduces and eventually the system dies. In this paper we introduce an efficient load sharing routing technique to increase the life time of all the nodes in a way to get maximum efficiency from the network. The routing algorithms such as link state which are used for wireless sensor networks prefer to choose a low cost path to decrease the transmission time but they do not consider the power of nodes for transmission which sometimes result in reduction of a lifetime of a network. We modify the previous method by saving the power of each node. A critical power is defined for a network and a node with power less than critical value is operated in power saving mode and is used only if there is no other substitute path available. A node in power saving mode set the cost of all the connected links to a very large value. When link state algorithm is applied on modified network, it is highly unlikely to get a low cost path with inclusion of such node unless a destination has only one path that includes this low power node. A computer simulation is performed to evaluate the performance of proposed algorithm. Our result clearly indicates an increase in lifetime of a network.