Query Processing in Multi-User Scenario for Wireless Sensor Networks

In wireless sensor networks (WSNs) how to judiciously utilize the limited energy capacity of sensor nodes is very important, especially in multi-user application scenarios. In this paper data query processing strategies are discussed and the multi-user scenario is defined. In this scenario, there is a large-scale monitored region with a large number of original queries requested from thousands of users. Such a huge number of query requests to sensornets are a heavy load for traditional query processing methods. To mitigate this problem, a novel query processing strategy, NER-MQ (Network Event Report based Multi-user Query), is proposed for these applications. In NER, queries from users can be processed at a Base Station (BS), and then sent to the exact event regions based on the information reported by the event reporting mechanism which is employed in NER. In order to restrict the distribution of queries within the event regions, a special subnet, termed as the embedded network (EN), is employed. Simulation results show that a significant performance improvement is gained with the proposed NER-MQ algorithm in the multi-user scenario of WSNs.