This document provides guidance on how to secure Industrial Control Systems (ICS), including Supervisory Control and Data Acquisition (SCADA) systems, Distributed Control Systems (DCS), and other control system configurations such as Programmable Logic Controllers (PLC), while addressing their unique performance, reliability, and safety requirements. The document provides an overview of ICS and typical system topologies, identifies typical threats and vulnerabilities to these systems, and provides recommended security countermeasures to mitigate the associated risks.
ICS cybersecurity programs should always be part of broader ICS safety and reliability programs at both industrial sites and enterprise cybersecurity programs, because cybersecurity is essential to the safe and reliable operation of modern industrial processes. Threats to control systems can come from numerous sources, including hostile governments, terrorist groups, disgruntled employees, malicious intruders, complexities, accidents, and natural disasters as well as malicious or accidental actions by insiders. ICS security objectives typically follow the priority of availability and integrity, followed by confidentiality.