A process model for software maintenance

This paper draws on work undertaken for the Butler Cox Productivity Enhancement Programme (PEP) to describe a process model which will provide a basis for overcoming the problems of cost and complexity associated with software maintenance. PEP is a continuous program that is open to organizations wishing to measure and improve systems development and productivity.The paper argues that for maintenance work to be effective, it is vital to control the input to the process – the procedure by which change requests are notified and managed in the first place. The procedure of change management is followed by impact analysis, system release planning, change design, implementation, testing and system release/integration. These steps, which occur sequentially, are supported by a further activity that continues concurrently – progress monitoring.The conclusion of the paper is that a coordinated program, effective across the whole maintenance process and designed to control changes to the system, will become more and more critical as the complexity of the system increases. Formal procedures are essential to ensure that software is not degraded and to provide an audit facility. At the same time there are several automated change and control packages now available that could help to reduce administrative overheads and increase control over system changes.