Evaluating Consistency Preservation for Multi-Domain Variability Propagation

Abstract

Today, model-driven engineering of variant-rich systems involves parallel development in multiple domains such as electronics, mechanics, and software. Rapid evolution can lead to inconsistencies, such as conflicting system models, which can have disastrous consequences in safety-critical functions (e.g. vehicle brakes). Even though partial solutions to both: single-domain variability modeling, and multi-domain consistency preservation exist, their combination remains unexplored. This paper presents a combined approach to consistency-preserving multi-domain variability propagation for variant-rich multi-domain systems. We exploit the incremental nature of two existing approaches. First, delta modeling, is a variability modeling technique to derive one product variant from another through the application of changes in the form of deltas. Second, the Vitruvius approach, which preserves multi-domain consistency via consistency preservation rules (CPRs) that react to model changes. The combination of both enables applying deltas in a source domain, which, via CPRs, leads to applying deltas in the target domain. We evaluate soundness and completeness of variability propagation as well as the influence of CPRs on both former properties. Soundness is assessed by checking whether propagated deltas and product variants are correct subsets of the respective manually written ones. Completeness measures how many expected elements of a delta/ product variant can be derived through variability propagation. Using an industry-related case study that models the variant-rich functionality of a vehicle’s body-comfort-system in multiple domain, results show that variability propagation yields sound target-domain deltas and product variants independent of CPRs. However, completeness is limited, and CPRs strongly influence the amount of required manual completion.