School of Technology Department of Computer Science Master Thesis Project 30p, Spring 2014 Challenges and success factors in the migration of legacy systems to Service Oriented Architecture (SOA) By Nataliya Vlizko Supervisor: Annabella Loconsole Examiner: Paul Davidsson Abstract Service-Oriented Architecture (SOA) provides a standards-based conceptual framework for flexible and adaptive systems and has become widely used in the recent years because of it. The number of legacy systems has already been migrated to this platform. As there are still many systems under consideration of such migration, we found it relevant to share the existing experience of SOA migration and highlight challenges that companies meet while adopting SOA. As not all of these migrations were successful, we also look into factors that have influence on the success of SOA projects. The research is based on two methods: a literature review and a survey. The results of the thesis include identification and quantitative analysis of the challenges and success factors of SOA projects. We also compare the survey results for different samples (based on the company industry, work area, size, and respondents experience with SOA and respondents job positions). In total, 13 SOA challenges and 18 SOA success factors were identified, analyzed and discussed in this thesis. Based on the survey results, there are three SOA challenges received the highest importance scores: “Communicating SOA Vision”, “Focus on business perspective, and not only IT perspective” and “SOA Governance”. The highest scored SOA success factor is “Business Process of Company”. While comparing different samples of the survey results, the most obvious differences are identified between the results received from people with development related job positions and people with business related job positions, and the results from companies of different sizes. Keywords: SOA, Service Oriented Architecture, SOA challenges, SOA migration, Legacy Systems, SOA success factors. ii Acknowledgement This thesis would not have been possible without the valuable contribution and guidance of certain people. First and foremost I offer my sincerest gratitude to my supervisor Professor Annabella Loconsole who has supported me throughout my thesis with patience and knowledge. I would also like to thank you my examiner Professor Paul Davidsson for valuable feedback and suggestions for improvement. Besides that, I would also like to thank the people who responded to the survey used in the research for their input. They have shared valuable insights in this study. Last but not least, I would like to show my deepest gratitude to my family for their support through my studies. iii Table of Contents Abstract .................................................................................................................................................... ii Acknowledgement .................................................................................................................................. iii List of Figures ....................................................................................................................................... viii List of Tables .......................................................................................................................................... ix List of Abbreviations ............................................................................................................................... x List of Terms ........................................................................................................................................... xi 1. Introduction .................................................................................................................................... 12 1.1 Problem ................................................................................................................................... 13 1.2 Existing research ..................................................................................................................... 13 1.3 Goals and Research Questions ................................................................................................ 14 1.4 Contributions ........................................................................................................................... 15 1.5 Thesis outline .......................................................................................................................... 15 2. Research methods .......................................................................................................................... 16 2.1 Literature Review ..................................................................................................................... 17 2.2 Survey...................................................................................................................................... 18 2.2.1 Data requirements ............................................................................................................ 18 2.2.2 Data generation method ................................................................................................... 19 2.2.3 Sampling frame, sampling techniques, response rate and sample size ............................ 22 3. Literature Review........................................................................................................................... 23 3.1 Challenges in migration to SOA ............................................................................................. 23 3.2 Description of SOA challenges based on literature review: ................................................... 25 3.2.1 Choosing the right migration strategy.............................................................................. 25 3.2.2 Communicating SOA vision. ........................................................................................... 26 3.2.3 Defining level of granularity. ........................................................................................... 27 3.2.4 Facilitate Reusability. ...................................................................................................... 27 iv 3.2.5 Focus on business perspective, and not only on IT perspective ...................................... 28 3.2.6 Implementations challenges. ............................................................................................ 28 3.2.7 Integration challenges. ..................................................................................................... 29 3.2.8 Managing cost. ................................................................................................................. 30 3.2.9 Organizational challenges ................................................................................................ 30 3.2.10 Performance. .................................................................................................................... 30 3.2.11 Program management challenges .................................................................................... 31 3.2.12 SOA Governance. ............................................................................................................ 31 3.2.13 Technology challenges..................................................................................................... 32 3.3 Success factors of SOA projects ............................................................................................. 33 3.4 Description of SOA success factors based on literature review: ............................................ 35 3.4.1 Agility .............................................................................................................................. 35 3.4.2 Budgeting and Resources ................................................................................................. 35 3.4.3 Business Process of Company ......................................................................................... 35 3.4.4 Close Monitoring ............................................................................................................. 36 3.4.5 Communication and collaboration ................................................................................... 36 3.4.6 Dependence on Commercial Products ............................................................................. 37 3.4.7 Facilitate Reusability ....................................................................................................... 37 3.4.8 Funding & Ownership...................................................................................................... 38 3.4.9 Information Architecture ................................................................................................. 38 3.4.10 Leadership ........................................................................................................................ 38 3.4.11 Legacy Architecture ......................................................................................................... 38 3.4.12 Management. .................................................................................................................... 39 3.4.13 Potential of Legacy System for being migrated ............................................................... 40 3.4.14 Principles, guidelines and standards ................................................................................ 40 3.4.15 SOA Governance ............................................................................................................