The conventional routing protocols in ad hoc networks are not well suited for the present communication networks and associated applications. The energy consumption of each mobile node is increasing drastically because of varieties of applications. Also, the mobility of nodes is increasing because of infrastructural changes in the world and density of mobile node is also increasing endlessly. The lack of response to these changes in the network of conventional routing protocol keeps them out from the operations. Furthermore, saving energy is a key parameter in designing a new routing protocol for ad hoc networks. Many a times mobile nodes have limited battery power and power consuming applications of nodes reduce energy of a node continuously which affects lifetime of node and thus, the overall network lifetime. The new route discovery process is required in all single path routing protocols exists in literature whenever the link is failed. This increases the delay and depletion of the resources. Reducing the frequencies of route discovery is the solution to decrease the delay and wastage of resources to increase the lifetime of node and hence the multi path routing is the better approach to use. In this paper, an energy conserving routing protocol is proposed which conserves the residual energy of nodes by appropriate selection of metric to improve the network lifetime. To realize this objective, we used the statistical approach to select the best path using priority. Using three metrics, residual energy of nodes, mobility of nodes and path length, we defined node reliability factor for individual path and total node reliability factor from all existing installed paths in routing table. The multipath selection mechanism uses overall node reliability factor. Higher the total node reliability factor, better is the path. These node reliability factors are the keys to save energy of the nodes by selecting the nodes whose energy is highest, mobility is lowest and path length is shortest. This proposed protocol improves the performance of multipath routing protocols of mobile ad hoc networks by elongating the lifetime of the network. We compared our proposed protocol with other protocols: ad hoc on-demand multipath distance vector (AOMDV) and its variants like ZD-AOMDV and AOMR-LM. The network lifetime, energy consumption and end-to-end delay are the performance parameters evaluated using simulations.

mobile ad hoc network, routing protocol, energy efficient, multipath.