3.1 A BRIEF HISTORY OF CYBER-PHYSICAL INTERACTIONS
3.1.1 Cyber-Physical Systems
There is a rapidly growing number of physical control systems that can be controlled electronically, connected to networks for remote access. They provide great benefits in automating previously manual control systems but pose a security risk if accessed by unauthorized third parties. These smart devices and ‘cyber-physical’ systems consist of a wide range of sensors, actuators, valves, switches, mechanical devices, and electronic controls that are generically known as operational technology (OT), to distinguish them from purely digital information technology (IT). In industry, they are sometimes called supervisory control and data acquisition (SCADA) systems and, for major pieces of machinery, industrial control systems (ICSs).1 Many electronic systems now contain elements of connectivity for diagnostic read-outs, upgrading and programming uploads, data transmission, and signal processing.
The proliferation of devices that are connected to the internet has given rise to the term ‘internet of things’ (IoT). This is also described as ‘the infrastructure of the information society’. It is estimated that there are currently around 28 billion devices connected to the internet, and various projections suggest that the number could reach 50 billion by 2020.2 The number of devices connected to the internet is currently increasing by 30% year on year.3 There are ...