Enhancing Network Availability by Tolerance Control in Multi-Sink Wireless Sensor Network

The limited energy in wireless sensor network has always been a key topic. Most previous studies usually regulate the network loading by periodically directing the data flow to different sinks in order to extend the overall life-time of network and enhance the network availability or data delivery. However, the time and place that an event occurred can not be estimated, thus regular information flow switching may not be able to balance the actual loading of network. Another, multiple paths to sinks for each node are established in the tolerance area defined by a pre-defined difference between the cost, i.e. hop counts away from sinks, of paths to different sinks such that each node in-between multiple sinks can distribute the forwarding burden among the paths to different sinks. Since sending data to a farther sink consumes much more overall energy of network, the gain of data delivery should be evaluated at the sacrifice of energy consumption. In this paper, a quantized model is proposed to evaluate the tradeoff between energy consumption and data delivery under non-uniformly events triggering in network. The tradeoff between network availability and energy consumption would be analyzed and the corresponding simulation results would be included.