Computer systems play an important role in our society. Software drives those systems. Massive investments of time and resources are made in developing and implementing these systems. Maintenance is inevitable. It is hard and costly. Considerable resources are required to keep the systems active and dependable. We cannot maintain software unless maintainability characters are built into the products and processes. There is an urgent need to reinforce software development practices based on quality and reliability principles. Though maintenance is a mini development lifecycle, it has its own problems. Maintenance issues need corresponding tools and techniques to address them. Software professionals are key players in maintenance. While development is an art and science, maintenance is a craft. We need to develop maintenance personnel to master this craft. Technology impact is very high in systems world today. We can no longer conduct business in the way we did before. That calls for reengineering systems and software. Even reengineered software needs maintenance, soon after its implementation. We have to take business knowledge, procedures, and data into the newly reengineered world. Software maintenance people can play an important role in this migration process. Software technology is moving into global and distributed networking environments. Client/server systems and object-orientation are on their way. Massively parallel processing systems and networking resources are changing database services into corporate data warehouses. Software engineering environments, rapid application development tools are changing the way we used to develop and maintain software. Software maintenance is moving from code maintenance to design maintenance, even onto specification maintenance. Modifications today are made at specification level, regenating the software components, testing and integrating them with the system. Eventually software maintenance has to manage the evolution and evolutionary characteristics of software systems. Software professionals have to maintain not only the software, but the momentum of change in systems and software. In this study, we observe various issues, tools and techniques, and the emerging trends in software technology with particular reference to maintenance. We are not searching for specific solutions. We are identifying issues and finding ways to manage them, live with them, and control their negative impact.

This book explores the domain of software maintenance management and provides road maps for improving software maintenance organizations. It describes full maintenance maturity models organized by levels 1, 2, and 3, which allow for benchmarking and continuous improvement paths. Goals for each key practice area are also provided, and the model presented is fully aligned with the architecture and framework of software development maturity models of CMMI and ISO 15504. It is complete with case studies, figures, tables, and graphs.

This book addresses the recent developments in systems maintenance research and practices ranging from technicality of systems evolution to managerial aspects of the topic, including issues such as evolving legacy systems to e-business, applying patterns for reengineering legacy systems to web, architectural recovery of legacy systems, evolving legacy systems into software components.

Software systems now invade every area of daily living. Yet, we still struggle to build systems we can really rely on. If we want to work with software systems at any level, we need to get to grips with the way software evolves. This book will equip the reader with a sound understanding of maintenance and how it affects all levels of the software evolution process.