Online energy aware routing in wireless networks

Online energy aware routing in wireless networks is the problem of finding energy efficient routes that maximize the network lifetime without the knowledge of future message flows. To maximize network lifetime, the paths for message flows are chosen in such a way that the total energy consumed along the path is minimized while avoiding energy depleted nodes. Finding paths which consume minimum energy and finding paths which do not use energy depleted nodes lead to conflicting objectives. In this paper, we propose two-phased energy aware routing strategies that balance these two conflicting objectives by transforming the routing problem into a multi-metric widest path problem. We find that the proposed approaches outperform the best-known algorithms in the literature. We also demonstrate a simple but insightful relationship between the total energy required along a path and the minimum remaining energy of a node along the path. We further exploit this relationship to show that staying within the solution space of paths with high residual energy and low total energy provides much improved lifetimes in general.