Rail control systems are becoming more complex with increased demands for harmonization and overall integration. The rail system is a shared responsibility in the industry, with an underlying conflict between traditional subsystem management and the need to achieve effects on higher system-level by modernization (digitalization).
Upgrades and renewal of rail control systems often become overly complicated when the new systems are integrated with existing subsystems. Unknown dependencies are discovered late, resulting in a loss of control.
The complexity in rail signaling is shown in many ways with the continuous delays and overdraft in budgets, e.g. ERTMS and cancellations of metro signaling contracts.
It has been underestimated from all positions and by all actors, but today we sense a recognition of the need for new approaches to meet these challenges.