Web IS Development Methodology (WISDM):WISDM and the IS development life-cycle

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3.5 WISDM and the IS development life-cycle

WISDM covers the analysis and design activities of system development. An IS development project also encompasses the construction of software and its operation and maintenance (figure 3.3). Software construction is discussed in chapter 10. There must also be testing and implementation, followed by operations and monitoring. These are largely outside the scope of this book, but they are essential aspects of the IS development life-cycle. There is no unidirectional flow seen in figure 3.3. The different life-cycles discussed in chapter 2 – waterfall, iterative, and evolutionary – are catered for in WISDM dynamics since all approaches must address the basic issues of analysis and design, software construction and implementation, and operation and maintenance. Thus, the traditional waterfall life-cycle is a special case: a requirements specification is produced and frozen and then passed on for refinement into a design and implementation in subsequent stages of the life-cycle. The specification might also be produced iteratively through RAD or evolve through successive prototypes.

Running throughout any IS development project is a concern for project management and quality management. This might be formalized as, for example, in PRINCE, the UK Government sponsored project management methodology, and the ISO9000 series of quality standards, or it might be less formal, for example, being driven by customer expectations and self-organizing teams.

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