The railway community is since 2015 working on the standardisation of FRMCS. The development of the future radio system is one of the “game changers” identified in the ERTMS Longer Term Perspective document of ERA. The Control Command System Technical Specification for Interoperability (TSI CCS) will incorporate FRMCS as the successor of GSM-R as the radio system to be used for train-to-track voice communications and for ETCS data communication, also supporting new railway functionalities such as ATO.