An efficient approach using domain knowledge for evaluating aggregate queries in WSN

In this paper, we study the problem of evaluating aggregate queries over a set of observations made by nodes in a wireless sensor network. The novelty of our solution is to use domain knowledge about the possible values of observations in order to reduce the number of observations required to evaluate the query. Reducing the number of observations required is important, because it reduces the energy cost and latency of answering the query. Two protocols for partial and opportunistic aggregate performance are presented. Opportunistic use of domain knowledge provides the best performance. Both protocols are more efficient than standard aggregate protocols because they allow earlier query completion.