Data caching-based query processing in multi-sink wireless sensor networks
Zhipeng Cai, Shouling Ji, Jinbao Li · International Journal of Sensor Networks · 2012
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.