Change-oriented version descriptions in EPOS

In EPOS,* software configuration management is based on the change-oriented versioning model. As part of a configured system specification, a version description is used to select the desired versions of different components that constitute the product. Furthermore, version descriptions are used to specify which versions are affected by a certain change. For large software systems comprising many variants, building a consistent configuration meeting specified requirements is not an easy task. In this paper, we propose a set of version description mechanisms and exemplify their use. An abstract description specifying the desired properties and functional requirements is expanded, using validities characterising properties of versions, preferences and defaults. We believe that the proposed mechanisms provide simpler, more intuitive and more compact descriptions of versions of large-scale software systems than conventional tools.