Connected dominating set based support-tree for top-k query in wireless sensor networks

Constructing underlying logic trees can effectively reduce the large communication overhead for centralized top-k query. In this paper, an energy-balanced optimal support-tree is proposed to solve the problem of earlier death for nodes near sink in sensor networks without fixed sink. This method aggregates node energy, degree and communication overhead, and nodes with low energy cost are chosen to be dominating nodes for data processing based on connected dominating set. In each query, nodes take turns to be root by location-based ID, which effectively balances the energy cost. The simulation experiment shows that top-k query based on support-tree outperforms the existing trees by similar query time, but lower average energy cost per round and balanced consumption among all sensor nodes after continuous top-k queries, which effectively prolong the network lifetime.