Event Processing Architectures leading to an EPTS Reference Architecture Adrian Paschke Freie Universität Berlin Paul Vincent Tibco Software Inc., UK Catherine Moxey IBM, UK Themis Palpanas University of Trento Brian Connell WestGlobal Alex Alves Oracle ABSTRACT We introduce a reference architecture for event processing, as defined by the EPTS reference architecture (RA) working group. An event processing reference architecture allows users to quickly create event processing solutions that adhere to known stakeholder requirements and architectural qualities, such as performance, scalability, and application coverage. The common EPTS reference architecture description is supported by the contributed event processing "architectures" from EPTS working group members, including multiple vendors and researchers. Categories and Subject Descriptors C.0; D.2.11 General Terms System architectures; Domain-specific architectures Keywords Event Processing, Complex Event Processing, Reference Architecture, Event-Driven Architecture 1. INTRODUCTION Event Processing (EP) is considered a new paradigm, or view, on information systems, and is realized in different vendor products and solutions. These incorporate various software technologies that provide an event-oriented view of systems, providing continuous and stateful views of incoming events. The use of multiple software techniques in high performance stateful event processing has resulted in associated specialized software and system architectures. To this end the Event Processing Technical Society (EPTS) set up a Reference Architecture group to provide a common Reference Architecture for event processing (EP). The goal is to define product- and system-independent abstractions and stakeholder views on current EP architectures and architectural practices. 2. TERMINOLOGY AND METHODOLOGY The EPTS Reference Architecture description follows the ISO/IEC 42010:2007 standard methodology for architectural descriptions of software intensive systems. [1] This methodology defines an architectural description as a collection of documentations of the architecture addressing different views on the system for different stakeholders. The six important terminological elements are: Architecture The fundamental organization of a system embodied in its components, their relationships to each other, and to the environment, and the principles guiding ist design and evolution. Architectural Description A collection of products that document the architecture. System A collection of components organized to accomplish a specific function or set of functions. System Stakeholder A system stakeholder is an individual, team, or organization (or classes thereof) with interests in, or concerns relative to, a system. View A representation of the whole system from the perspective of a related set of concerns. Viewpoint A specification of the conventions for constructing and using a view - a pattern or template which to develop individual views by establishing the purposes and audience for a view and the techniques for its creation and analysis. For further information on the underlying conceptual reference model and reference methodology we refer to [2]. For the terminology of event processing concepts and components used in the EPTS RA description we also refer to the EPTS Glossary. [3] For the EPTS Reference Architecture description we have currently defined two views – a functional view and a logical view – which address typical stakeholders such as the business analyst, the IT operations manager, the software architect / designer. 3. ARCHITECTURES The EPTS RA group have combined "architectural diagrams" (representing product and system specific architecture information) from multiple sources - including vendors with customers using their technologies in everyday use - to derive some common architectural definitions. Some of these input architectures are based on implemented system architectures while others are a generic representation of possible specific architectures. At the time of writing two main architectural views have been described: logical and functional architectures.