1 Scope
This document provides railway operators, system integrators and product suppliers,
with guidance and specifications on how cybersecurity will be managed in the context
of EN 50126‑1 RAMS lifecycle process. This document aims at the implementation of a consistent
approach to the management of the security of the railway systems. This document can
also be applied to the security assurance of systems and components/equipment developed
independently of EN 50126‑1:2017.
This document applies to Communications, Signalling and Processing domain, to Rolling
Stock and to Fixed Installations domains. It provides references to models and concepts
from which requirements and recommendations can be derived and that are suitable to
ensure that the residual risk from security threats is identified, supervised and
managed to an acceptable level by the railway system duty holder. It presents the
underlying security assumptions in a structured manner.
This document does not address functional safety requirements for railway systems
but rather additional requirements arising from threats and related security vulnerabilities
and for which specific measures and activities need to be taken and managed throughout
the lifecycle. The aim of this document is to ensure that the RAMS characteristics
of railway systems / subsystems / equipment cannot be reduced, lost or compromised
in the case of cyber attacks.
The security models, the concepts and the risk assessment process described in this
document are based on or derived from the IEC/EN IEC 62443 series. This document is consistent with the application of security management requirements
contained within IEC 62443‑2‑1, which in turn are based on EN ISO/IEC 27001 and EN ISO 27002.

