Success factors in managing legacy system evolution: A case study

In this paper, we attempt to understand what contributes to a successful process for managing legacy system evolution. We provide an analysis of a number of key performance indicators such as cost, duration, and defects. By normalizing through function points, we furthermore compare to a larger benchmark. To do so we performed a mixed, retrospective case study on a series of nine software releases and eight single once-only releases, all performing on a single, legacy software system, in a West-European telecom company. We interviewed eleven stakeholders that were closely involved in the subject software releases. As a result, we listed a number of observations from the quantitative and qualitative analysis. We found that a release process that performs above average on cost and duration satisfies stakeholders through fast response and direct value, even when the reliability and availability of the actual system is weak.Software EngineeringSoftware Technolog