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. The authors 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