The University of British Columbia

In wireless sensor networks, data aggregation is used to collect local data from neighboring nodes (sources) and generate a data report. In this paper, we propose E-span, which is an energy-aware spanning tree algorithm. E-Span is a distributed protocol and facilitates the sources within an event region to perform data aggregation. In E-span, the source node which has the highest residual energy is chosen as the root. Other source nodes choose their corresponding parent node among their neighbors based on the residual energy and distance to the root. By selecting the directed diffusion [C. Intanagonwiwat et al., Aug. 2000] as the underlying routing platform, simulation results show that the lifetime of sources can be extended significantly when E-Span is used.