How does adherence to the Purdue Model enhance cyber resilience in an Operational Technology (OT) environment, particularly concerning threat containment and impact limitation?

Adherence to the Purdue Model significantly enhances cyber resilience in an Operational Technology (OT) environment by establishing a hierarchical, segmented architecture that inherently supports robust threat containment and impact limitation. The Purdue Model, also known as the Purdue Enterprise Reference Architecture, divides industrial networks into logically and often physically separated zones, each with distinct functions and security requirements. These levels, ranging from Level 0 (Process/Sensors/Actuators) up to Level 5 (Enterprise Network), are separated by Level 3.5, the Industrial Demilitarized Zone (IDMZ), which acts as a crucial buffer between the sensitive OT network and the broader IT enterprise network.