A Look into the Future of Digital Signalling Technology: Digirail Project in Finland Unites Pioneers

The advantages of an open system architecture, in which different components from various manufacturers are installed and integrated, are clear for railway operators. Growing competition is changing pricing structures, for example. Furthermore, it enables more flexible planning of maintenance work. Expansion and modernisation projects are also easier to implement: increasing modularity allows the renewal of subsystems without complete replacement of the signalling system. This significantly reduces planning and approval efforts. The Finnish Transport Infrastructure Agency FTIA is taking a pioneering role and implementing a forward-looking project in which all relevant aspects come into play – including new challenges.

He is convinced: "Like all pioneers, we naturally face various challenges during implementation – and we learn from every step. What is clear is that the open system architecture will require considerable expertise from all parties involved in integrating individual components, particularly on the operator side. To manage this, FTIA is working closely with all the companies involved."

This became evident during the integration tests at the Ratateknisen Oppimiskeskus (ROK), the Track Technology Learning Centre in Kouvola. Thanks to the on-site facilities, initial tests took place here between October and November 2025 under real conditions. The tracks and point machines available at ROK correspond to those in the field. The signalling processes here are already controlled via the Siemens interlocking platform DS3, which is also being used in the Digirail project.

A team of experts conducted tests in Kouvola on interlocking integration and interface conformity of the developed solutions with the Relesoft test system. It quickly became clear that the extensive preparation work had paid off: the Frauscher object controllers delivered precise results immediately after activation and configuration.

The new point control solution, FAdP Point, also fulfilled its tasks without any issues. Various simulations had already correctly processed different fictitious interlocking commands beforehand – however, without transmission to a physical point. Now the results were tangible: various Siemens point machines could be controlled and monitored without difficulty via the established EULYNX interface standard SCI-P. Commands from the interlocking were correctly processed and transmitted. The monitoring of point end positions was particularly interesting. The test with real configuration parameters confirmed that this also functions under real conditions.

An important building block in establishing digital interlockings and network-based system architectures is naturally the topic of cyber security. "The EULYNX interface standard provides an excellent foundation in this regard," says Stefan Neudorfer, Product Security & Network Manager at Frauscher: "Beyond the seamless integration of different components, linking safety and security is one of the greatest challenges the railway faces with increasing digitalisation in the signalling technology sector. The project in Finland demonstrates that we are on the right track with our solution. Overall, the industry will need to rethink its approach in some areas. Conversely, new approaches in the security sector will of course also be needed to meet the requirements of safe railway operations."

Accordingly, a key objective of the integration tests at ROK was also the configuration of secure communication channels. After the parameters of all interfaces with the Siemens interlocking were adjusted in a configuration phase, the Frauscher team implemented a security layer for encrypted communication with the interlocking. "We were well prepared here too and had a plug-and-play solution ready," recounts Neudorfer – drawing a positive conclusion: "Here too, my colleagues on site saw that the intensive development phase had paid off. Our solution worked practically immediately."

The Frauscher team was thus able to leave behind a fully integrated and configured system upon departure. In the next step, this will be thoroughly examined by the responsible experts at FTIA. Following completion of the relevant procedures, deployment in the field will follow, as Harald Murauer summarises: "Thanks to the excellent collaboration with Siemens, MIPRO, Relesoft and FTIA, we have been able to complete all project steps on time and successfully to date. We now look forward to all components being installed and commissioned in the field along the Digirail line – which will take place in the first half of this year."