Traffic Management System (TMS) / CTC

The TMS receives real-time status from interlockings and train detection, showing dispatchers where every train is and which routes are set. Dispatchers issue route requests from their workstations, or the system sets them automatically according to the timetable (automatic route setting). It also handles disruptions by re-planning paths, adjusting platform allocations and passing revised schedules to passenger information systems.

The TMS itself is not a safety system: the interlocking still checks and rejects any unsafe request. This separation lets the TMS run on ordinary IT platforms and integrate with timetable planning, crew and fleet management, maintenance systems and, increasingly, passenger-facing applications.

The TMS is the largest bridge between the enterprise IT world and signaling. It exchanges data with business systems, is used by many operators through standard workstations and often connects to every interlocking on the network. Compromising it does not directly cause an unsafe movement, but it can bring a whole network to a standstill or be used as a staging point toward the safety systems behind it.

Several real-world rail incidents involved control-center or dispatching systems rather than field equipment. Segmenting the TMS from the interlocking network, controlling the interfaces between them and monitoring the commands that cross that boundary are central requirements in standards such as IEC 62443 and the TSA security directives.