European Rail Traffic Management System (ERTMS)
ERTMS is the EU standard for train control and rail radio communications. It is set out in the CCS TSI and deployed through onboard and trackside systems so trains can run across borders without changing national protection systems.
What it includes
ERTMS is typically used as an umbrella term for:
ETCS (European Train Control System): train protection and supervision
GSM-R: the legacy radio network for ETCS; the CCS TSI also references migration to FRMCS
How it works in practice
In operations, functions are split between equipment on the train and systems along the line:
Onboard: speed supervision, braking curve enforcement, driver interface
Trackside/radio: route data and radio connectivity. In radio-based operation, movement authorities are delivered over the radio.
Why it is deployed
ERTMS is rolled out to reduce fragmentation and support cross-border operation with domestic-like predictability. It can also support higher capacity by enabling continuous supervision and, where used, cab signalling—reducing reliance on lineside signals.
EU TEN-T policy sets deployment targets: the Core Network by 2030 and the Comprehensive Network by 2050.
Compatibility and authorisation
Technical backward compatibility is described by ERA (for example, how certain onboard and trackside baselines can interwork).
Separate from that, placing CCS subsystems in service requires demonstrating conformity with the CCS TSI requirements through the authorisation process (under the EU rail safety/interoperability framework).
History
Key milestones include:
Late 1980s–early 1990s: European work begins on common train control and rail radio concepts
1996: EU high-speed interoperability rules formalise the need for interoperable control-command and signalling
2017: the Commission adopts an ERTMS European Deployment Plan, with milestones initially set for 2017–2023
2023: the CCS TSI is updated via a new implementing regulation, replacing the prior CCS TSI framework