Pre-Requirement Specification Traceability: Bridging the Complexity Gap through Capabilities

Abstract: Pre-Requirement Specification traceability is the activity of capturing relations between requirements and their sources, in particular user needs. Requirements are formal technical specifications in the solution space; needs are natural language expressions codifying user expectations in the problem space. Current traceability techniques are challenged by the complexity gap that results from the disparity between the spaces, and thereby, often neglect traceability to and from requirements. We identify the existence of an intermediary region -- the transition space -- which structures the progression from needs to requirements. More specifically, our approach to developing change-tolerant systems, termed Capabilities Engineering, identifies highly cohesive, minimally coupled, optimized functional abstractions called Capabilities in the transition space. These Capabilities link the problem and solution spaces through directives (entities derived from user needs). Directives connect the problem and transition spaces; Capabilities link the transition and solution spaces. Furthermore, the process of Capabilities Engineering addresses specific traceability challenges. It supports the evolution of traces, provides semantic and structural information about dependencies, incorporates human factors, generates traceability relations with negligible overhead, and thereby, fosters pre-Requirement Specification traceability.