Designing and Enacting Cross-organisational Business Processes: A Model-driven, Ontology-based Approach Stephan Roser Dissertation Programming Distributed Systems Department of Computer Science University of Augsburg ii Supervisor: Prof. Dr. Bernhard Bauer (University of Augsburg) Advisors: Prof. Dr. Jörg P. Müller (Clausthal University of Technology) Prof. Dr. Wolfgang Reif (University of Augsburg) Day of defense: 9th May 2008 Copyright © Stephan Roser, Augsburg, March 2008 Abstract Under the pressure of globalization, companies are urged to constantly adapt to new market situations and competitors innovations. Focusing on their core business and core competencies, they engage in Cross-organisational Business Processes (CBPs) with new partners all over the world in ever changing constellations. Companies are organized into global networks and outsource those activities that can be performed more quickly and effectively or at lower costs, by others. These developments create new challenges for enterprise Information and Communication Technology (ICT), requiring ICT sys- tems to support constantly changing enterprise collaboration relationships and to create application systems that support or automate business process enactment starting from business level descriptions and models of CBPs. Model Driven Software Development (MDSD) provides techniques to realize and automate the propagation of changes at the business level to the technical level. MDSD can be used to provide end-to-end support for the realization of business processes, from the business level (users’ view) down to deployed applications (ICT view) on specific platforms via well-defined, largely automated model transformations and refinements. However, there still exist several problems that prevent MDSD from being practically applicable for efficient and effective CBP enactment. This thesis provides contributions that enable MDSD projects to improve their pos- sible impact on software development and the way ICT systems support business. It develops solutions to three main problems, namely for the areas of CBP modelling and enactment infrastructure, ICT architecture selection, and model and transformation evo- lution. The contributions of this thesis are as follows: 1. We develop architecture patterns, a code generation framework, and model trans- formations that facilitate the generation of executable code from high-level, do- main-specific models. These artifacts help to bridge the semantic gap between domain-specific, high-level business process descriptions and the technologies used to implement them in service-oriented ICT systems. Domain and IT ex- perts benefit since our contribution provides a set of sensible and customizable transformations they can reuse to improve the development of their ICT systems. 2. We investigate new evaluation and decision methods as well as guidelines for the selection of appropriate ICT architectures. We develop a model for decision sup- port that helps IT architects to derive an appropriate architecture paradigm for a given use case or application domain. The decision model combines the Analytic Hierarchy Process (AHP) with scenario-based architecture evaluation techniques. Further, we describe how contingencies influence ICT system coordination archi- tecture. Our decision method, the scenario descriptions, and a set of guidelines iv help IT architects to select and reuse appropriate ICT system coordination archi- tectures for CBP enactment in a timely manner. This helps to gain productivity wins by reducing the development time and improving the quality of development with existing and tested solutions. 3. We develop the Ontology-based Model Transformation (OntMT) approach that fa- cilitates the exchange of models between different enterprises as well as the reuse and evolution of model transformations. OntMT helps to overcome differences in syntax and semantics of modelling formalisms with as little effort as possible. Therefore, we apply semantic and reasoning technology to the domain of MDSD. We develop a higher-order model transformation language that allows to modify model transformations. Organisations and modellers benefit from OntMT since it allows them to exchange, customize, and evolve models and model transforma- tions more efficiently. Acknowledgements I would like to thank all people that supported me in writing my thesis: • First of all, I am deeply grateful to my supervisor Prof. Dr. Bernhard Bauer for giving me the opportunity to conduct research in the field of Model Driven Soft- ware Development. His guidance, support, and motivation were the basis for the successful completion of this thesis. • I am also indebted to Prof. Dr. Jörg P. Müller for his support in the ATHENA IP project as well as for his feedback and contribution to joint research and publica- tions. He also volunteered to be advisor of my thesis. • I want to thank Prof. Dr. Wolfgang Reif who accepted to be advisor of my thesis. • Special thanks go to my colleagues from the Programming Distributed Systems group (in alphabetical ordering) Wolf Fischer, Holger Kasinger, Florian Lauten- bacher, Raphael Romeikat, and Viviane Schöbel, who created a friendly and cheer- ful working atmosphere that I enjoyed a lot. Each of them contributed in his own way to this thesis, e.g. by working together in projects, discussing joint research, or sharing everyday work with me. • I want to thank all students that helped me to save time with their implementations and to improve the results of my work with their valuable feedback. • Especially, I want to thank all other people, who directly or indirectly influenced this thesis. The fruitful discussions with them at workshops and conferences as well as in research and industrial projects were an important source of inspiration. • I gratefully thank all my friends who shared their leisure with me. Their informal support and encouragement had positive influence on this thesis. • Finally, I want to thank my parents Hannelore and Hans-Dieter Roser. They have always supported and encouraged me to do my best in all matters of life. Contents 1 Introduction 1 1.1 Problems and Challenges ......................... 3 1.2 Objectives, Approach, and Contributions ................. 5 1.3 Outline .................................. 7 2 Basics 11 2.1 Service-oriented Paradigm ........................ 11 2.2 Process Modelling and Execution .................... 14 2.2.1 Orchestration & Choreography .................. 18 2.2.2 Process Modelling ........................ 18 2.2.3 Cross-organisational Business Processes ............. 19 2.3 Architecture Evaluation and Decision Methods ............. 21 2.3.1 Architecture Evaluation ..................... 21 2.3.2 Analytic Hierarchy Process .................... 23 2.3.3 Contingency Theory ....................... 24 2.4 Semantic Technologies and Technological Spaces ............ 25 2.4.1 Technological Spaces ....................... 25 2.4.2 Ontology ............................. 27 2.4.3 Syntax, Semantics, and Ontology ................ 29 2.5 Summary ................................. 30 3 Model Driven Software Development 31 3.1 MDE Approaches to Software Development ............... 32 3.1.1 MDA ............................... 32 3.1.2 Software Factories ........................ 35 3.1.3 Benefits of Model Driven Engineering .............. 35 3.1.4 MDE Tool Suites and Initiatives ................. 36 3.2 Models .................................. 38 3.2.1 MegaModel for MDE ...................... 38 3.2.2 Metamodelling Hierarchy .................... 40 3.2.3 UML vs. Domain Specific Languages .............. 41 3.2.4 Types of Models ......................... 42 3.2.5 Models as Assets of Organisations ................ 44 3.3 Model Transformation and Code Generation ............... 44 3.3.1 Features of Model Transformations ............... 48 3.3.2 Classification of Model Transformation Approaches ...... 50 3.3.3 OMG Standard: Query/View/Transformation .......... 53 3.4 Summary ................................. 59 viii CONTENTS 4 Enacting Cross-organisational Business Processes with MDSD 61 4.1 Transforming CIM to PIM ........................ 62 4.1.1 Problem Description ....................... 62 4.1.2 Software Architectures for ICT System Coordination ...... 63 4.1.3 Case Study ............................ 66 4.1.4 Implementation and Execution CIM to PIM Model Transforma- tions ................................ 68 4.1.5 Discussion ............................ 73 4.2 Transforming PIM to PSM ........................ 73 4.2.1 Context and Example ....................... 74 4.2.2 Problem Description ....................... 75 4.2.3 Model and Code Generation Framework ............. 79 4.2.4 Case Study ............................ 81 4.2.5 Discussion ............................ 84 4.3 Conclusions ................................ 85 5 ICT Architectures for CBP Enactment: Applicability Criteria and Evalua- tion 87 5.1 Example and Problem Description .................... 88 5.2 A Method for Evaluation of ICT Architecture Applicability ....... 89 5.2.1 Methodological Issues ...................... 89 5.2.2 Multi-criteria Evaluation and Decision Model .......... 90 5.2.3 Measuring Qualitative Factors .................. 92 5.2.4 Measuring Quantitative Factors ................. 100 5.3 Applying the Evaluation Method ..................... 102 5.3.1 Virtual Enterprise Scenario .................... 102 5.3.2 SME Scenario .......................... 105 5.4 Discussion and Conclusions ....................... 107 6 Ontology-based Model