The digitalisation of Europe’s railways starts with a dependable communications backbone

The digitalisation of Europe’s railways has the potential to enhance efficiency and make rail more attractive to passengers. It can also play an important role in maintaining the sector’s high safety standards. But leveraging this potential requires new technologies that can span the digital divide between the rail of today and that of tomorrow. For example, current railway operations depend on rigid processes and legacy systems for situation and status monitoring, as well as the signalling between track side equipment/signals and controls.

While this setup works well for the current mode of operations, where trains travel in block distance, it doesn’t allow room for the level of flexibility that the future of rail will demand.

Digitalisation, on the other hand, brings with it a transformative impact. For instance, through real-time data utilisation and the automation of certain features and processes, digitalisation will have a direct impact on network capacity, enabling trains to run at shorter distances.

Traffic management is another area ripe for digitalisation. Whereas traditional rail relies on fixed schedules and manual oversite, which can be both inefficient and liable to human error, a digital system (e.g. automated train control, automated train operation) optimises train schedules and can dynamically manage traffic flow – leading to higher efficiency and better use of the railway infrastructure.

So, how do we go about shrinking this digital divide?

A good place to start is with efficient and secured communication. Having a robust and dependable communication backbone capable of carrying the signalling and data load is the key to realising digitalisation’s full potential. Helping to build this backbone is the Europe’s Rail Joint Undertaking (EU-Rail).

The initiative has delivered a portfolio of technical demonstrators (TD) that address the key issues relating to developing the dependable communication and signalling needed to enable advanced train management and control systems. These include:

• Adaptable communications for all railways: Define and demonstrate a communication system for the advanced traffic management and control that will be used in future railway systems and ensure backward compatibility with existing systems.
• Cybersecurity: Define approaches for protecting the railway system from third party threats and attacks.
• On-board train integrity: Develop innovative approaches for establishing a train’s integrity.
• Traffic management system: Develop and demonstrate new approaches to traffic management.

Adaptable communications for all railways

 The development of a new communication system aims to address the future needs of the European Train Control System (ETCS), along with other applications. Specifically, it looks to provide a versatile train-to-ground communication system that can:

• Facilitate easy migration from existing systems (e.g. GSM-R)
• Enhance throughput
• Improve safety and security functionalities
• Support the evolving needs of signalling systems
• Mitigate the risk of interference
• Adapt to the ongoing advancements in radio technology
• Maintain backwards compatibility with ERTMS

To address these needs, EU-Rail delivered several solutions and demonstrators:

Business models and cost comparison

The rollout of a future railway communication system will be different for each country or region (depending on the actual situation and legacy technologies). This solution allows users to study possible business models and compare operational and capital costs. Railway network and infrastructure providers can use this generic tool to roll out a new communications backbone.

Antenna system for an adaptable communication system

By thoroughly evaluating antenna solutions capable of adapting to different wireless communication systems, network operators will be able to use equipment with different radio interfaces. This in turn will enable the multipath communication needed to increase the reliability and availability of the connections between rolling stock and track side.

Technical demonstrators for different use cases

Integrating antennas and existing building blocks into demonstrators shows how an adaptable communication system can support different types of railway systems and traffic types (e.g. highspeed/mainline, freight/regional, urban/suburban). Rail network operators, along with rail operators, will benefit from the increased efficiency this work enables.

Discussion

 At least for the foreseeable future, achieving wireless connectivity along railway lines will remain challenging. That’s because rolling out a private railway network that can provide most rail lines with adequate coverage to transport the signalling and data streams used to ensure the secure and efficient operations that support different levels of ETCS is both costly and time consuming.

These three demonstrators show how public communication infrastructure (e.g. 5G networks) can immediately provide rail with the reliable and dependable communication it needs.

Specifically, the highspeed/mainline demonstrator showed that commercial (public) operator networks based on 5G stand-alone architectures are sufficiently mature to support future railway operations. The freight/regional demonstrator showcased the use of multiple radio technologies to transport ETCS messages over different radio systems (e.g. terrestrial 4G, satellite links). This proved the usefulness of the adaptable antenna system, as well as verified that multipath communication is a viable means of ensuring reliable and dependable delivery of ETCS messages.

Last but not least, the urban/suburban demonstrator showed that the required quality of service can be delivered even over different bearer networks. While limitations were observed (e.g. WiFi hotspots), the use of public cellular networks proved to be a viable alternative to a private railway network.

Key findings   Viable business cases exist for (temporarily) using cellular infrastructure as part of a railway communication backbone. Using multiple radio technology and wireless communication systems can deliver the reliability and quality of service needed to enable ETCS in different scenarios, applications, and use cases. Flexible bearers and multipath technology are promising approaches to facilitating a continuous service provision for railway signalling and data traffic. Field tests proved to be valuable and gave further results not only due to the dynamics at different speed, but also in terms of stability and maintainability. At least two sets of field test runs would be recommended to fix issues that cannot be solved immediately and also to address issues in the environment of the system under test (e.g. simulations of applications).

Conclusion

There is a strong case for using public communication infrastructure to supplement and complement the railway communication system. The shared use of private (railway) communication infrastructure and public communication networks is a viable way of ensuring quality of service and reliability in signalling and communication during the interim period while a network-wide private (railway) communication system is built.

Next steps

The results of the work done by Shift-2-Rail is being taken to the next step by Europe’s Rail, where further activities are expected to be done around ACS, linked to the GigaBit Train. Prototypes are to be developed addressing specific use cases around regional lines, in addition to exploring how the ACS concept could feed a future evolution of FRMCS.

Cybersecurity

Railway communication systems require a robust, cost-effective defence against cyberattacks and other threats. To help address this need, EU-Rail delivered several solutions and demonstrators:

Security by design guidelines

Security by design is an approach where all systems are designed and implemented with cybersecurity as a core consideration. This means conducting a thorough risk assessment to pinpoint where actual cybersecurity risks and vulnerabilities exist within railway communication across different scenarios. Infrastructure operators and train operators can use these guidelines to help protect such high-risk assets as the signalling and data communication between trains, between train and trackside, and along the track side.

Verification along the supply chain

Following a comprehensive investigation, review, and analysis of how security requirements from all supply chain providers are adhered to and implemented, a document was prepared describing whether and how various component and system providers can implement the security-related requirements outlined in relevant standards. Doing so will result in an auditable trail verifying that all actors (infrastructure providers, train service providers, equipment manufacturers) adhere to all security related standards.

Broader risk and security assessment

A better understanding of risks and security threats will be essential to achieving a flexible, advanced traffic management system. To help provide infrastructure and train operators and equipment manufactures with such an understanding, a wide-ranging risk and security assessment was conducted – one that considered both communication system(s) and the complete processes needed to implement automatic train operations (ATO) and next generation train control networks (NG-TCN).

Security model, prototyping, and validation

A coherent model and defined procedures are at the core of every security architecture, and this demonstrator provided a defined rail-specific cyber-defence reference model and validated procedures that all actors can use to implement system-wide cybersecurity.

Key outcomes Comprehensive catalogue of risk and cybersecurity threats. Far-reaching guidelines and recommendations for adapting a security by design approach that can be used by equipment manufactures and system designers. In-depth understanding of how security-related standards are implemented across the supply chain, with a particular focus on how COTS can be used in products and services. A security model that can complement the security approaches already being used by the rail community.

Conclusions

 When it comes to the safe and reliable operation of railway networks, cybersecurity is simply non-negotiable. This is particularly true for systems that demand higher levels of flexibility and more efficient traffic management. The work carried out within these TDs will provide equipment manufactures and infrastructure/train operators with the insight they need to implement the necessary cybersecurity safeguards.

Next steps

Cybersecurity aspects are being taken as a centrepiece of the modular functional rail architecture that is being developed by the EU-RAIL System Pillar. Demonstrators will be expected to prove the cybersecurity by design concept in the Europe’s Rail programme.

On-board train integrity

 To leverage the efficiency and capacity gains that automation promises, it is essential that one knows a) whether the train is intact and b) where on the line the end of the train is at any given moment.

To help deliver both, this TD developed and prototyped an innovative on-board solution that autonomously locates the train’s tail, enables wireless communication between the tail and the front cab, and safely detects any interruptions to the train.

The work, which targets freight and low-traffic lines that currently lack such capabilities, involved:

Cost/benefit analysis

This work analysed the costs involved in equipping Europe’s many freight wagons and regional trains with onboard train integrity solutions and the benefits such technology will provide. It was determined that such a system will benefit track and train operators as being able to know if the train is intact and the exact position of the last wagon will enable the introduction of a more dynamic and efficient traffic management and control system.

Demonstration, validation, and simulation of on-board train integrity monitoring systems

Three TDs (one test environment, two system simulators) were built to demonstrate and evaluate the reliability and validity of different approaches to achieving onboard train integrity (OTI). The test environment provides a platform for the independent evaluation of the solutions, while the simulators offer an outlook on the scalability of the solutions. The work has provided equipment manufacturers with valuable insights on the feasibility and operational issues of their individual OTI solutions.

Discussion

Due to its impact on safety, efficiency, and automation, train integrity will be crucial to the advanced traffic management and control systems used in future railways. By providing accurate data on train positions, train integrity can prevent collisions and other accidents. It can also enable optimised scheduling, increase capacity, and ensure smoother and more efficient rail traffic.

For automated systems, reliable train integrity makes consistent and precise operations without human intervention possible and facilitates seamless signal system integration. It also reduces maintenance costs, enhances the passenger experience, and supports interoperability and data sharing between different rail systems.

In other words, train integrity, including the OTI systems developed in these demonstrators, underpins the effectiveness and reliability of advanced rail traffic management and control systems.

Key outcomes   Three demonstrators were implemented and evaluated to prove the performance of OTI systems. The cost/benefit analysis provides a solid evaluation of the costs of implementing such OTI systems and the potential gains they would generate if widely deployed.

Conclusion

 The findings from the demonstrators and simulations not only provide proof about the feasibility and performance of OTI systems, but also a detailed migration plan and business case of how such systems could gradually be introduced into the railway networks.

Next steps

Additional demonstrations will take place during the Europe’s Rail programme, which will also collaborate on the development of Digital Automatic Coupling (DAC).

Traffic management system

 An optimised traffic management system (TMS) looks to enhance traffic operations through automated integration and exchange with other rail services. To achieve this, it will feature a scalable, interoperable, and standardised communication structure within an integrated rail management system. This will in turn be combined with advanced applications, such as driver advisory systems and intelligent dispatching systems, allowing for predictive and dynamic traffic management.

The system will also use real-time status and performance data coming from both the network and trains, supported by wireless communication, to effectively manage both regular and disrupted situations.

Here, the TD presented a large number of demonstrators showcasing numerous functions and features and providing a thorough evaluation that helps clarify the complexity of the overall system and forms an excellent basis for further integration.

The solutions rely on the following key developments:

The integration layer

The integration layer provides standardised interfaces (API), messages (semantic and serialisation) and reliable communication protocols. In order to design such a solution, the work takes into account the main data blocks, its characteristics, use cases (e.g. run time calculation) and user requirements when analysing the available integration patterns and choosing the most efficient solution.

The IL will enable seamless data exchange between TMS applications from different vendors. The designed solution will provide additional services for resource management to solve high availability issue and central monitoring and configuration, enabling one ‘system’ view on the deployed components. Besides helping to reduce lifecycle costs, such an approach will also enable new intelligent functions. For example, the integration layer allows easy access to the standardised information available in TMS that will be required by future intelligent functions.

The application framework

Application framework allows for the separation of big monolithic applications into many fine-grained micro-services, taking over the responsibility for the failover, control, and monitoring of them. Application framework was put forward as a solution to provide a standardised development and runtime platform for a variety of TMS applications, running on top of the integration layer.

A scalable, interoperable and standardised communication structure applicable within an integrated rail services management system has been developed and serves as a backbone for the exchange of data between traffic management, freight operations, and asset management services. Such a standardised framework/platform for business service applications will support existing use cases in railway traffic, as well as enable new use cases that make use of the advanced TMS principles.

These two elements served as a basis for supporting the development of prototype applications, addressing key use cases for TMS, such as:

Integration layer for data exchange of trackside equipment for ATO (Grade of Automation 2)

This demonstrator exploits the integration layer that connects track side equipment and installations and forwards this information to the various entities involved in ATO. With ATO being an integral feature of advanced traffic management, all related actors can gain from the results this demonstrator provides.

TMS business applications demonstrator

Understanding when and where deviations from normal operations or disturbances on the tracks occur is an essential feature and capability for advanced traffic management. This demonstrator implements applications that mitigate the impact of traffic disturbances and unexpected infrastructure restrictions.

Integration of field status information

Knowing the operational state of track side equipment and being reliably updated when this state changes is a precondition to achieving the efficiency and safety that advanced traffic management must offer. This demonstrator integrates the data from field elements to establish and derive field status information.

Connected driver advisory system

This demonstrator looked at computing the speed profile, as well as driving modalities, both of which are needed to inform a connected driver advisory system. This work supports the driver and improves the quality of the information provided to the driver at any given time.

Conflict detection and resolution

Based on the information obtained via the integration layer, this demonstrator implements business logic and services for detecting, showing, and managing future conflicts that may occur during operation. This will allow train operators and traffic managers to prevent or pre-empt potential conflicts at an early stage, ideally before they become operational obstacles.

Interactions between the asset management and the train monitoring systems

The interactions between field equipment and different monitoring services may vary between different use cases and scenarios. By evaluating various scenarios/use cases and validating the functionality of the integration layer and the associated communications layer, this demonstrator helps increase trust in the overall architecture and platform.

Conflict detection system

Complex control systems have a generally high likelihood of becoming deadlocked. This demonstrator aimed to show that deadlock situations can be avoided, or at least limited, if the information obtained has already been analysed and the potential deadlocks were detected before they could influence a state of transition.

Discussion

These use cases and demonstrators show that much of the operational complexity found in advanced traffic management systems can be accommodated within a future management system. Whether that system be ATO or TMS, the key is to have dependable information from track side equipment and that the exchange of this information be secure and reliable. Furthermore, a dependable integration layer that manages the exchange of sensor and control data is at the core of the system and directly relies on the communication subsystem.

Key outcomes Key use cases and features, along with the main principles for the design and testing of prototypes/demonstrators, were defined and specified. 7 different demonstrators were successfully implemented and evaluated, each tackling a particular aspect and feature necessary to facilitate ATO and other crucial functions of advanced traffic management and control systems.

Conclusions

The demonstrators presented cover a large number of features and functions necessary for future railway operations in which ATO may be mixed with traditional train operations. The demonstrators, while not yet covering all the necessary features, show a wide range of capabilities, and the approach taken is highly methodological and will clear a viable path towards integrating these different parts into a common demonstrator

Next steps

The next steps must include bringing the individual demonstrators together into one large scale showcase.

Traffic Management System is a core part of the Europe’s Rail programme, with work focusing on developing solutions for both capacity management (e.g. planning) and operations (traffic management).

Enhancing the overall railway network

A robust communication backbone is needed to carry the data that advanced signalling and automated train operations demand. The Europe’s Rail Joint Undertaking is developing adaptable communication systems, cybersecurity measures, on-board train integrity solutions, and traffic management systems to address this need.

These advancements support the integration of flexible, efficient, and secure traffic management and control systems, enhancing the overall railway network. What’s needed now is to integrate these individual solutions into a comprehensive system for future railway operations.