Concurrent Model Synchronization with Conflict Resolution Based on Triple Graph Grammars

Triple graph grammars (TGGs) have been used successfully to analyse correctness of bidirectional model transformations. Recently, also a corresponding formal approach to model synchronization has been presented, where
updates on a given domain (either source or target) can be correctly (forward
or backward) propagated to the other model. However, a corresponding formal
approach ofconcurrentmodel synchronization, where a source and a target modification have to be synchronized simultaneously, has not yet been presented and
analysed. This paper closes this gap taking into account that the given and propagated source or target model modifications are in conflict with each other. Our
conflict resolution strategy is semi-automatic, where a formal resolution strategy
– known from previous work – can be combined with a user-specific strategy.
As first result, we showcorrectnessof concurrent model synchronization, that
is, each result of our nondeterministic concurrent update leads to a consistent
correspondence between source and target models, where consistency is defined
by the TGG. As second result, we showcompatibilityof concurrent with basic
model synchronization: concurrent model synchronization can realize both forward and backward propagation. The results are illustrated by a running example
on updating organizational models.