A Query Service for Raw Sensor Data

摘要

Sensor networks generate a compact form of data in order to efficiently use the available power of the device. Query engines require a richer form of this data in order that users can express meaningful and useful queries. This enrichment of the sensor stream leads to an inevitable increase in the volume of data transported across the network. If this data is enriched and stored in a database on the same server and used only for offline queries, matters such as enrichment time and increased data volumes can usually be managed quite efficiently. However, when there is a requirement to query sensor output in real time, the time required to enrich data and increased data volumes lead to slow query response times. In this research, we present the liveSensor system which offers the benefits of an enriched sensor stream, providing a high level query interface to the user. However, it delays the enrichment of sensor data until after query results have been generated and thus, maintains a high level of performance by processing raw sensor streams.