Authors: Zhipeng Cai; Shouling Ji; Jinbao Li
Addresses: Department of Computer Science, Georgia State University, Atlanta, GA 30303, USA. ' Department of Computer Science, Georgia State University, Atlanta, GA 30303, USA. ' School of Computer Science and Technology, Key Laboratory of Database and Parallel Computing of Heilongjiang Province, Heilongjiang University, Harbin, Heilongjiang 150080, China
Abstract: In multi-sink Wireless Sensor Networks (WSNs), different sinks may issue same queries and therefore they can share some common query results. As a classical data-sharing method, data caching is employed widely in traditional databases and it can also bring benefits in WSNs thanks to the emergence of sensors with Flash Memory. Therefore, a query-processing method based on common subtree (CS) caching in multi-sink WSNs is proposed. We first construct CSs and then cache the results of processed queries at the roots of CSs. Subsequently, later common queries can obtain their expected results from the common roots. Furthermore, in order to achieve a higher degree of data sharing, we propose a loop-removing algorithm. Extensive simulations indicate that the proposed method can reduce the energy consumption and the query response time significantly for WSNs.
Keywords: multi-sink WSNs; wireless sensor networks; data management; query processing; data caching; data sharing; flash memory; simulation; energy consumption; query response time.
International Journal of Sensor Networks, 2012 Vol.11 No.2, pp.109 - 125
Received: 10 Nov 2010
Accepted: 13 Jul 2011
Published online: 19 Mar 2012 *