Optimization of in-network data reduction

We consider the in-network computation of approximate “big picture” summaries in bandwidth-constrained sensor networks. First we review early work on computing the Haar wavelet decomposition as a User-Defined Aggregate in a sensor query engine. We argue that this technique can be significantly improved by choosing a function-specific network topology. We generalize this discussion to a loose definition of a 2-level optimization problem that maps from a function to what we call a support graph for the function, and from there to an aggregation tree that is chosen from possible subgraphs of the physical network connectivity. This work is frankly quite preliminary: we raise a number of questions but provide relatively few answers. The intent of the paper is to lay groundwork for discussion and further research.

• Type: Conference
• Year: 2004
• Where: DMSN
• Authors: Joseph M. Hellerstein, Wei Wang
• Keywords: Bandwidth-constrained Sensor Networks, DMSN 2004, Haar Wavelet Decomposition, Sensor Query Engine