An Approach to Query Decomposition for Reader Level Filtering in RFID Middleware

In RFID systems, middleware is used to filter enormous streaming data gathered continuously from readers to process application requests. The high volume of data makes middleware often in a highly overloaded situation. Nowadays, readers are becoming smart and provide filtering functionality. The reader filtering capability can be used to reduce data volume as well as middleware work-load. However, if middleware dispatches query conditions to reader without any adjustment, it may generate huge amount of duplicate data which imposes considerable load on the middleware. So, the appropriate schema of data volume reduction is required. In this paper, we propose a query decomposition technique to divide queries into sub-queries for middleware and reader level execution. This new approach of query execution resolves the problem of duplicate data generation. Our experiments show that the proposed approach considerably improves the performance of middleware by reducing the query processing time and the network traffic between reader and middleware.