An approximation algorithm for data storage placement in sensor networks

Data storage has become an important issue in sensor networks as a large amount of collected data needs to be archived for future information retrieval. This paper proposes to introduce storage nodes that can store data collected from the sensors in their proximities. The storage nodes alleviate the heavy load of transmitting all the data to a central place for archiving and reduce the communication cost induced by the network query. This paper considers the storage node placement problem to minimize the total power consumption for data funneling to the storage nodes and data query. We formulate it as an integer linear programming problem and present an approximation algorithm based on a rounding technique. Our simulation shows that our approximation algorithm performs well in practice.