A Framework for the Specification of Acquisition Models

This report describes a framework for the specification of acquisition models. The exposition is formal in nature. The framework is defined in terms of activities, events, requirements, and instances of a system. In addition, various relations among these items, such as the relation between acquisition activities and acquisition events, are defined. The timing properties associated with the items receives special treatment. The value of a framework is that one can develop specifications of various acquisition models, such as waterfall, spiral, or incremental, as instances of that framework. Formalizing the specification of an acquisition model has benefit in that one can reason about the characteristics of the domain addressed by the model. When this is done for multiple acquisition models, each derived from the same framework, it is possible to compare different acquisition approaches.