The management of software with a long life span

Experience, particularly in the US military field, has highlighted the problems of escalating software support costs in computer-based systems. This has resulted in the realization that software should be developed with the aim of minimizing through-life support costs rather than initial procurement costs, thus allowing software to be supported over periods of up to 20 years and be transported over successive generations of hardware without the major cost of replacement of the software. Although the problems of designing and implementing software which is capable of a long life span are becoming better understood, the problems associated with the management of software to achieve this life span are less well understood. This paper discusses topics such as quality plans, documentation standards and configuration management and describes the methods which may be applied to the management of software to enable the benefits of the initial investment to be realized.