Large-scale Cyber-Physical Systems (CPS) represent the new frontier for distributed computing and, in particular, Cloud computing. In such systems, there is a tight need for effective and efficient distributed query processing tasks, which may be implemented within the core layer of conventional middleware. In particular, autonomous embedded devices (also known as motes) and wireless sensor networks appear to be the most convenient computational infrastructures to implement and deploy CPS effectively and efficiently. Within this so-delineated research context, in this paper we propose architecture and functionalities of StreamOperation (StreamOp), a middleware for supporting distributed query processing via a novel paradigm that lies on the autonomous database management metaphor to be implemented on each mote of the system. We also provide experimental analysis and assessment which clearly validate our research even from a performance-oriented point of view, beyond the conceptual point of view ensured by our main contributions.
