As part of our work on a standardized interface for exchanging models for gear calculation (www.rexs.info), we have defined a modeling structure for gears. Different component types are available as building blocks (e.g. shafts, bearings, gears). These can be connected to each other via component-specific relations. For example, there is a stage_relation with the roles "stage", "gear 1", "gear 2" for a gear stage or a side_relation that connects a bearing with two other components. Most relations have 2 or 3 roles, or components that connect them. So the model structure resembles a graph. Now it is in most cases so that such a model in the interface format can be imported by different tools and thereby into their internal data structure is transferred which deviates from this modeling structure (at least partly). If the model is exported then again thereby in many cases the Ids of components and relations change. After importing and exporting, certain aspects of the model may be more or less detailed than before (depending on what the tool can do and what it requires). This poses a challenge when you want to compare the two model states. The idea is therefore to create a matching between the two models based on the similarity of the model structure, which identifies related components. In the seminar I would like to describe the REXS modeling system, outline the matching problem and discuss if there are any solutions that could be modified for the concrete problem.