Developing Legacy System Migration Methods and Tools for Technology Transfer

This paper presents the research results of an ongoing technology transfer project carried out in coopera- tion between the University of Salerno and a small software company. The project is aimed at developing and transferring migration technology to the industrial partner. The partner should be enabled to migrate monolithic multi-user COBOL legacy systems to a multi-tier Web-based architecture. The assessment of the legacy systems of the partner company revealed that these systems had a very low level of decompos- ability with spaghetti-like code and embedded control flow and database accesses within the user interface descriptions. For this reason, it was decided to adopt an incremental migration strategy based on the reengineering of the user interface using Web technology, on the transformation of interactive legacy programs into batch programs, and the wrapping of the legacy programs. A middleware framework links the new Web-based user interface with the Wrapped Legacy System. An Eclipse plug-in, named MELIS (migration environment for legacy information systems), was also developed to support the migration process. Both the migration strategy and the tool have been applied to two essential subsystems of the most business critical legacy system of the partner company

Migrating a Large Scale Legacy Application to SOA: Challenges and Lessons Learned

Abstract—This paper presents the findings of a case study of a large scale legacy to service-oriented architecture migration process in the payments domain of a Dutch bank. The paper presents the business drivers that initiated the migration, and describes a 4-phase migration process. For each phase, the paper details benefits of using the techniques, best practices that contribute to the success, and possible challenges that are faced during migration. Based on these observations, the findings are discussed as lessons learned, including the implications of using reverse engineering techniques to facilitate the migration process, adopting a pragmatic migration realization approach, emphasizing the organizational and business perspectives, and harvesting knowledge of the system throughout the system’s life cycle. I

Evaluating Legacy System Migration Technologies through Empirical Studies

We present two controlled experiments conducted with master students and practitioners and a case study conducted with practitioners to evaluate the use of MELIS (Migration Environment for Legacy Information Systems) for the migration of legacy COBOL programs to the web. MELIS has been developed as an Eclipse plug-in within a technology transfer project conducted with a small software company [16]. The partner company has developed and marketed in the last 30 years several COBOL systems that need to be migrated to the web, due to the increasing requests of the customers. The goal of the technology transfer project was to define a systematic migration strategy and the supporting tools to migrate these COBOL systems to the web and make the partner company an owner of the developed technology. The goal of the controlled experiments and case study was to evaluate the effectiveness of introducing MELIS in the partner company and compare it with traditional software development environments. The results of the overall experimentation show that the use of MELIS increases the productivity and reduces the gap between novice and expert software engineers

Mainframe Migration based on Screen Scraping

Companies possess a history and large array of legacy information systems that consume a great part of their IT budget in operations and maintenance. These systems are mission-critical, and they cannot be fully discarded since they retain business rules and provide information that is not available anywhere else. Unfortunately, decades-old legacy systems cannot easily withstand modification. Mainframes specifically conglomerate most of these legacy systems. Although there are some white-box solutions for migrating mainframe systems, such solutions lack systematicity and do not provide mechanisms for verifying business rules preservation. Hence, this paper presents a black-box solution (ignoring the internal structure of COBOL programs) which uses a screen scraping technique for migrating mainframe systems toward JavaFX and relational databases. Together with this solution, this paper provides an automatic verification technique to check if the recreated system reflects all the embedded business logic. This proposal has been designed and developed in the context of an industrial project, in which the solution has already migrated 43,000,000 mainframe screens from four systems. The main implication for researchers and practitioners is that screen scraping has proved to be feasible for migrating mainframe systems in large-scale projects within a manageable time-frame while preserving business

Appendix To Software Migration: A Theoretical Framework A Grounded Theory approach on Systematic Literature Review

Software migration has been a research subject for a long time. Major research and industrial implementations have been conducted, shaping not only the techniques available nowadays, but also a good part of Software evolution jargon. To understand systematically the literature and grasp the major concepts is challenging and time consuming. Even more, research evolves, and it does based on the assumption that there is a single meaning that we all share redounding in the pollution of words with multiple and many times opposite meanings. In our quest to understand, share and contribute scientifically in this domain, we recognise this situation as a problem. To tackle down this problem we propose a taxonomy on the subject as a theoretical framework grounded on a systematic literature review. In this study we contribute a bottom-up taxonomy that links from the object of a migration t

Factors Affecting Success in Migration of Legacy Systems to Service-Oriented Architecture (SOA) - Shared Experiences from Five Case Companies

Background: The term ‘legacy systems’ refers to existing Information Systems that have been deployed in the past and have been running critical business processes within an enterprise in its current IT architecture. Based on their important role, legacy systems are considered the heart of a company’s operating enterprise system and therefore are of significant business value to the company. Therefore IT architects have not neglected the value these existing assets can bring to the adoption of service-oriented architecture and have been studying different methods and factors to migrate the legacy investments into the new architecture and take advantage of their business value. However, not in all cases has the process of migrating legacy systems into SOA been successful. In fact, the level of success in adapting the legacy systems in a company with the new service-oriented architecture is dependant on some factors which vary from one legacy infrastructure and series of business processes to another. There is no quick fix to transforming the existing legacy assets which highlights the fact that considering the right factors to reach legacy system migration success in a specific company is of key value. Therefore, we hereby studied the factors influencing success of migrating these legacy investments into SOA in five different companies which include a Large European Bank, SAS, a Large globally-known Company in Sweden, Sandvik AB and a large UK Bank. Purpose: To identify factors affecting successful migration of legacy systems into SOA in five companies. Method: The main adopted research method in this study has been interviews for different case studies. Through separate interviews, critical success factors of migrating legacy systems into SOA have been collected and identified in each case. Finally collected results are analyzed and presented as the recognized factors affecting successful migration of legacy assets into SOA in five different enterprises with their own Information System infrastructures. Conclusion: The success factors identified include potential of legacy systems for being migrated, strategy of migration, SOA governance, the business process of the company, budgeting and resources, legacy architecture, close monitoring, dependence on commercial products, information architecture, testing and technical skills of the personnel. Out of all these factors, only three factors have been applied and mentioned by all the case companies in this study, which are the potential of legacy systems for being migrated into SOA, strategy of migration and SOA Governance

Pitfalls and guide lines in the transition to object oriented software design methodologies

A research report submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering.Due to the dynamic nature of the software engineering industry there is a constant move towards new strategies for solving design problems. More specifically there is a move towards Object Oriented (OO) methodologies, presumably because of the various advantages offered in terms of maintainability, and reuse of code produced this way. As with various other aspects of the software industry there are however also problems encountered in this transition and lessons to be learned from the experience of companies who have already performed this change. This research report investigates possible guidelines for companies who are currently contemplating a change to the OO software design methodologies, by covering a collection of issues one should know about prior to this change. It also summarises the problems faced in the transition so far, the reasons for these problems and suggests possible solutions. Lastly it also investigates new trends in the OO arena. The emphasis is on South African companies and projects. The results obtained are compared with results obtained overseas to find out what the differences and similarities are. Areas of concern are also identified, where theoreticians' views have been ignored, and both South African and overeeas companies have not implemented any of the suggestions made.Andrew Chakane 201

Re-engineering strategies for legacy software systems

Re-engineering can be described as a process for updating an existing system in order to meet new requirements. Restructuring and refactoring are activities that can be performed as a part of the re-engineering process. Supporting new requirements like migrating to new frameworks, new environments and architectural styles is essential for preservation of quality attributes like maintainability and evolvability. Many larger legacy systems slowly deteriorate over time in quality and adding new functionality becomes increasingly difficult and costly as technical debt accumulates. To modernize a legacy system and improve the cost effectiveness of implementing new features a re-engineering process is often needed. The alternative is to develop a completely new system but this can often lead to loss of years of accumulated functionality and be too expensive. Re-engineering strategies can be specialized and solve specific needs like cloud migration or be more generic in nature supporting several kinds of needs. Different approaches are suitable for different kinds of source and target systems. The choice of a re-engineering strategy is also influenced by organisational and business factors. The re-engineering of a highly tailored legacy system in a small organisation is different from re-engineering a scalable system in a large organisation. Generic and flexible solutions are well suited for especially smaller organisations with complex systems. The re-engineering strategy Renaissance was applied in a case study at Roima Intelligence Oy in order to find out if such a strategy is realistically usable, useful and valuable for a smaller organization. The results show that a re-engineering strategy is possible to be used with low overhead in order to prioritize different parts of the system and determining a suitable modernization plan. Renaissance was also shown to add value especially in the form of deeper understanding of the system and a structured way to evaluate different options for modernization. This is achieved through assessing the system from different views taking into account especially business and technical aspects. A lesson learned about Renaissance is that determining an optimal scope for the system assessment is challenging. The results are applicable for other organisations dealing with complex legacy systems with constrained resources. Limitations of the study are that the number of different kinds of re-engineering strategies discussed is small and more suitable strategies than Renaissance could be discovered with a systematic mapping study. The amount of experts participating in the process itself as well as the evaluation was also low, introducing some uncertainty to the validity of the results. Further research is needed in order to determine how specialized and generic re-engineering strategies compare in terms of needed resources and added value

MoDisco, a Model-Driven Platform to Support Real Legacy Modernization Use Cases

International audiencePresentation of a model-driven migration chain used by Sodifrance on its projects and of Eclipse/MoDisco platform a new model-driven framework to develop legacy modernization tools