An Initial Tracing Activity Model to Balance Tracing Agility and Formalism Requirements Tracing Strategies for Change Impact Analysis and Re-Testing

Software customers want both sufficient product quality and agile response to requirements changes. Formal software requirements tracing helps to systematically determine the impact of changes and keep track of development artifacts that need to be re-tested when requirements change. However, full tracing of all requirements on the most detailed level can be very expensive and time consuming. In this paper we introduce an initial “tracing activity model”, a framework that allows measuring the expected cost and benefit of tracing approaches. We apply a subset of the activities in the model in a study to compare 3 tracing strategies, ranging from agile “just in time” tracing to fully formal tracing, in the context of re-testing in an industry project at a large Austrian bank. In the study a) the model was found useful to capture costs and benefits of the tracing activities to compare the different strategies; b) a combination of upfront tracing on a coarse level of detail and focused just-in-time detailed tracing can help balancing tracing agility (for use in practice) in a formal tracing framework (for research and process improvement).