MicroCEP: Complex Event Processing on the Edge

The Internet of Things (IoT) has experienced rapid growth, taking advantage of advanced data processing. While complex event processing (CEP) engines have positioned themselves as a good solution for cloud and fog data processing, there are no CEP solutions designed to run on microcontrollers (MCUs) at the edge. This paper presents MicroCEP, a software architecture for MCUs that enables real-time filtering and correlation of sensor data, both locally obtained and received through message queues at the edge. MicroCEP provides (i) a lightweight CEP architecture for MCUs, (ii) a pattern language to specify complex event patterns, (iii) a REST API for dynamic threshold updates, and (iv) a methodology for designing and deploying MicroCEP-based systems. The solution facilitates the detection of situations of interest and the triggering of actions directly from the MCUs, enabling autonomous decision-making close to the sensors. A proof of concept implementation using RISC-V MCUs provides evidence that MicroCEP can deliver CEP capabilities at the edge on resource.constrained devices.