Information Management II / ERP: Microsoft Dynamics NAV 2009 Page 1 of 5 PART 3: MODELLING BUSINESS PROCESSES EVENT-DRIVEN PROCESS CHAINS (EPC) Event-driven Process Chains are, in simple terms, some kind of flowchart a diagram to visualize business process workflows. They can be used to set up ERPs and for business process improvement. 1 Introduction An Event-driven Process Chain is a semiformal, graphical modelling technique which was developed by G. Keller, M. Nüttgens, and A.-W. Scheer in 1992 for a research project of the SAP AG but widely accepted and used by many companies for modelling, analyzing, and redesigning business processes today. An EPC is supported by business modelling tools like ARIS-Toolset, ADONIS of BOC Group, Mavim Rules of Mavim BV, Business Process Visual ARCHITECT of Visual Paradigm, Visio of Microsoft Corp., Semtalk of Semtation GmbH, or Bonapart by Pikos GmbH and directly used in SAP R/3, Bonapart, and others. 2 Modelling Elements and Rules of EPC Modelling The EPC consists of different elements to graphically display process flows which are briefly explained in the following: Function Event Connector Functions are active elements (processes) and describe a task or activity within the company. They transform input to output data from an initial state to a resulting state. Furthermore, they can be refined into other EPCs down to elementary functions. They are labelled by [verb in infinitive]+[topic/object], e.g. Order the material Events are passive elements and represent occurred economical or technical states. They trigger functions and describe under which circumstances a function works or which state the function results in. There are two kinds of events: Activating event, labelled by [topic/object]+ is to be +[past participle], e.g. The material is to be ordered Final event, labelled by [topic/object]+( was +)[past participle], e.g. Material (was) ordered In linear processes events and functions are connected by arrows directing the control flow. However, since processes do not only take place in linear fashion, the basic elements in an EPC can also be connected by three different kinds of logical connectors to split and synchronize paths:
Information Management II / ERP: Microsoft Dynamics NAV 2009 Page 2 of 5 Conjunction AND Adjunction OR Disjunction EXCLUSIVE OR If business processes become more complex, hierarchies within control flows can be built by using these elements: Process interface/connector They show the connection from or to other processes in the business process model. Process refinement This symbol indicates that the function shown incorporates the entirety of another process which is depicted in more detail in a separate graph.! All EPCs begin with one or more activating events and end with one or more final events, never with functions.! Only functions, not events, can make decisions which means that an event cannot be connected upstream of an adjunction (OR) or a disjunction (XOR). The following matrix of possible connectors illustrates this relationship for better understanding:
Information Management II / ERP: Microsoft Dynamics NAV 2009 Page 3 of 5 3 EPC in Examples These templates are supposed to assist the definitions of the forgone part and to demonstrate their functionality: Dividing events Parallel flows Alternative flows
Information Management II / ERP: Microsoft Dynamics NAV 2009 Page 4 of 5 Process interface: Reference to another chain in order to illustrate the part Procurement of the business process more detailed. Process refinement: Refinement of a function in a second process chain.
Information Management II / ERP: Microsoft Dynamics NAV 2009 Page 5 of 5 4 Extended EPCs (eepc) An EPC can be extended in order to describe not only single business processes but also their entire organization. Here, functions are connected with additional elements information objects such as input, output, system resources, and organization units in order to access, create, or change data. 5 Literature Primary sources for lecture (also in Engl. available): Scheer ARIS - Vom Geschäftsprozess zum Anwendungssystem, 2002 Scheer ARIS - modellingsmethoden, Metamodelle, Anwendungen, 2001 Rosemann, M. (1996): Komplexitätsmanagement in Prozessmodellen: Methodenspezifische Gestaltungsempfehlungen für die Informationsmodelling. Wiesbaden. Schmelzer, Sesselmann: Geschäftsprozessmanagement in der Praxis, Hanser- Verlag, 2004, ISBN 3-446-22876-4 For a first overview: Wikipedia: http://en.wikipedia.org/wiki/event-driven_process_chain