QStream: Deterministic Querying of Data Streams

Current developments in processing data streams are based on the best-effort principle and therefore not adequate for many application areas. When sensor data is gathered by interface hardware and is used for triggering data-dependent actions, the data has to be queried and processed not only in an efficient but also in a deterministic way. Our streaming system prototype embodies novel data processing techniques. It is based on an operator component model and runs on top of a real-time capable environment. This enables us to provide real Quality-of-Service for data stream queries.