The railroads must be able to offer high-quality services for both the high-speed trains and the conventional ones. So, these objectives imply a search for a harmonization of the European rail network. For this purpose, the European Union set up a European management system of the rail traffic — the ERTMS system (European Rail Traffic Management System) — to ensure, in full safety, trains circulations on different European networks. As the full deployment of this system will be long and expensive, evolutions will be necessary and will raise other technological challenges. This paper presents methods, models, and tools dedicated to the generation of tests scenarios for the validation of ERTMS components based on functional requirements.