The railroads must be able to offer high-quality services for 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 an 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. It is composed of the controlcommand system named ETCS (European Train System Control) and the GSM-R, the new radio system for voice and data communication. As the full deployment of this system will be long and expensive, evolutions will be necessary and raises 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.