Transforming Railways: Cutting-Edge Signalling Systems With Wayside Object Controllers

Traditional centralised railway systems often face significant challenges when it comes to scalability. These systems are typically designed in a fixed way, meaning they can handle limited operational complexity. As a result, any attempts to upgrade or expand such systems to increase operational capacity or integrate new technology often become too costly and complex.

Modern Wayside Object Controllers (WOCs) equipped with the EULYNX interface offer a robust solution to issues faced by traditional centralised railway systems. WOCs enable the creation of decentralised railway architectures, which presents the operator with a wide array of benefits, such as lower set-up and maintenance costs, more flexible and efficient system upgrades, greater scalability, alongside many others, as explored in this article.

WOCs must meet several essential requirements to ensure optimal performance and integration within modern railway systems. These requirements include upholding the highest standards of safety and security, offering a diverse range of connectivity options and providing a high degree of modularity. WOCs are able to achieve these requirements largely thanks to standardised interfaces such as EULYNX.

The EULYNX architecture comprises the following interfaces, which are used for standardised data exchange between wayside objects and interlocking systems:

SCI (Standard Communication Interface): This interface handles the transmission of commands and messages. Safety-relevant information such as the status of track sections (free or occupied) and reset commands are communicated through the RaSTA (Rail Safe Transport Application) protocol.

SDI (Standard Diagnostic Interface): This interface is dedicated to diagnostic data. Using an OPC-UA server, it provides detailed diagnostic information about the wayside objects and components. This allows for real-time monitoring and analysis, helping to quickly identify and resolve issues.

SMI (Standard Maintenance Interface): The SMI enables maintenance tasks to be executed. Including configuration updates, software and patches and ensures that maintenance activities can be performed efficiently and securely.

SSI (Standard Security Interface): This interface standardises the communication related to security services between the Security Services Platform (SSP) and the EULYNX subsystems. It supports certificate, key, and authentication management as well as security logging by being connected to a security service platform.

A robust network connectivity is crucial as it enables WOCs to communicate seamlessly with both the interlocking system and a centralised data management system. Furthermore, thanks to EULYNX, WOCs enable a high degree of interoperability between various system components. The ability to choose from different manufacturers of components without vendor lock-in promotes greater product diversity and grants the operator significantly more choice in procuring components according to specific project requirements and irrespective of the manufacturer.

Using WOCs in conjunction with standardised interfaces also enables the different life cycles of the signalling components and field elements to be decoupled. In practice, the decoupling of life cycles represents considerable cost saving for the operator, as only the affected components are replaced, without major changes to the entire system. Utilising WOCs therefore future proofs the railway system as operators can incorporate and adopt emerging technologies into the existing infrastructure in a seamless and cost-efficient way.