Powerful, flexible and cost-effective analyses of maritime systems can be conducted in an appropriate way with distributed simulations. Co-simulation components require interoperability like specified by the IEC TC/65/290/DC to insure information exchange and synchronization. Therefore this paper describes a way to insure the interoperability of co-simulations of maritime systems. User-and technical requirements for these co-simulations are derived to create a deeper understanding for especially the necessity of a common semantic model. Furthermore, six integration layers are presented for co-simulation-based analysis. They are derived from IEC TC/65/290/DC and the conceptual architecture approach for co-simulation systems. The paper introduces a semantic model approach to reflect the requirements formal description of the simulation model, observability, controllability and interoperability. The model is used to configure the inter-process communication of the used co-simulation architecture. This is done by an automatic model transformation from the semantic model to the platform specific implementation.