Lifetime-throughput tradeoff for elastic traffic in multi-hop hotspot networks

Multi-hop hotspot networks consist typically of one or few wireless access nodes (ANs) and many self-organizing, self-coordinating, and battery-powered portable nodes (PNs). Nodes maintain cooperative connectivity among each other without any need for a wired infrastructure. On the one hand, because PNs are power-limited, efficient use of their available energy resources is crucial to their lifetimes. On the other hand, because higher rates of elastic flows provide higher QoS, it is desirable to maximize the throughput. Unfortunately, increasing lifetime and maximizing throughput are two conflicting objectives which cannot he optimized simultaneously. In this paper, we propose an extension of our earlier-presented scheme (B. Hamdaoui et al., IEEE Press Monograph on Sensor Network Op., 2004) to support elastic traffic routing in multi-hop hotspot networks. The proposed routing scheme strikes a balance between the need to keep the nodes operational with sufficient energy resources and the desire to allocate higher throughput to elastic flows. The proposed scheme also deals systematically with both objectives of maximizing the network lifetime and minimizing the total consumed energy.