ViBES: virtual backbone for energy saving in wireless sensor networks

Prolonged lifetime, robustness and scalability are important requirements in wireless sensor networks (WSNs). In this paper we show that via the energy-efficient construction of a connected backbone and a simple stateless routing over the backbone, it is possible to achieve these desired goals. We present a ns2 simulation-based comparison between data dissemination in WSNs when a) each sensor routes the sensed data to the sinks directly (flat network organization), and b) a backbone is constructed on top of the flat network topology and only a few nodes are in charge of data delivery to the sinks (hierarchical organization, here termed ViBES: virtual backbone for energy saving). Multiple targets (i.e., moving nodes) are allowed to roam throughout the network of static sensors. Simulations are performed on networks of increasing densities where up to 3 targets are identified and reported to up to 3 sinks. Our results show that routing through the backbone increases the network lifetime up to seven times over the flat network organization where network lifetime is defined as a) the time till the first node dies because of energy depletion, b) the time required for a given percentage of the network nodes to die, and c) the time required for the network to get disconnected.