Deriving a unified fault taxonomy for event-based systems

Dependability and fault-tolerance, which are key requirements for business- or safety-critical applications, require explicit knowledge of potential faults that may occur within a system. In contrast to other major research directions, the emerging field of distributed event-based systems is yet lacking a common understanding of faults. In this paper we take a step forward and study potential origins and effects of faults in such systems. Our work on a unified fault taxonomy follows a rigorous methodology. We first identify five core sub-areas in the broader field of event-based systems, and discuss commonalities and differences among them. Then we derive from the existing literature a coherent domain model, which accurately captures the specifics of the different areas. The domain model provides a holistic view and covers both structural and procedural aspects of event-based systems. Based on this model, we elaborate a detailed taxonomy of faults, in line with well-established fault dimensions from dependable and secure computing. The fault taxonomy forms the basis for a comprehensive discussion of fault instances across the five sub-areas of event processing.