Until recently, there were no cybersecurity solutions dedicated to the safety-critical networks in railway systems. NTT and Cylus recognized this critical gap.
Oct 3, 2019

The first commercial railway systems were deployed in the 19th century. Since then, they have served as a key mode of transporting people and goods all around the world. While in the past, railways were controlled mainly by complex mechanical systems and relied heavily on the manual exchange of communications, modern railway systems have moved towards operating largely via digital components, taking the human factor out of the equation. Signaling systems have undergone significant advances to ensure that trains stay clear of each other at all times.
The following components demonstrate the technological sophistication of modern signaling systems:
- Computer-Based Interlocking (CBI) - computerized systems that are in charge of overseeing trackside signals in a safe manner. Trackside signals consist of light signals, point machines, axle counters, and others.
- Automatic Train Protection (ATP) - computerized system that constantly monitors the speed of the train and activates the brakes in the event that the train moves faster than allowed by the signaling system. Newer systems also support Automatic Train Operation (ATO), which enables the full automation of train movement in addition to other safety capabilities.
These following components have been introduced to railways in different geographies and via different systems, but they all rely on similar foundations:
- The European ERTMS (European Rail Traffic Management System) introduces standardization to interfaces between the train ATP (called OBU) and trackside equipment (called RBC).
- The urban transit CBTC (Communication-Based Train Control) allows for a higher degree of automation and also supports shorter spacing between trains by introducing a concept called “Moving Blocks”, in which the train receives its braking curve dynamically and the stoppage distances are not fixed. This is in contrast to the older “Fixed Blocks” systems in which the blocks are predefined.
- The US-based PTC (Positive Train Control) mandate requires all trains to operate with ATP systems.
