Multi-level feature trees - A pragmatic approach to managing highly complex product families

Feature modeling has become a popular technique for domain analysis and variability management. However, it is still a considerable challenge to apply this technique to product families and organizational contexts of high complexity like the product range of a global automotive corporation. Managing everything as a single product family with a global feature tree is virtually impossible owing to the enormous complexity, but if the product range is split up into several smaller, independent product lines with separate feature models, systematic reuse and strategic variability management across these portions is lost. In this article, we present multi-level feature trees, which offer a compromise between a single global and several smaller, independent feature trees. Other development artifacts may also be arranged in this way if the multi-level concept is adapted to them. This is shown exemplarily for requirements artifacts in Telelogic Doors. Finally, we describe scenarios showing how this concept can be put into practice.