A fabric controller is a cybersecurity component designed to collect and analyze network data from operational technology (OT) switches without requiring the installation of agents or software on individual devices. It operates by passively monitoring network traffic, often through port mirroring or SPAN ports, to gather insights into data flows, device communications, and potential security threats within industrial environments. This agentless approach minimizes disruption to critical systems and reduces the risk of impacting device performance or stability. Fabric controllers are commonly used in industrial control systems (ICS) and other OT networks to enhance visibility, detect anomalies, and support compliance with security standards, all while maintaining the integrity and reliability of essential infrastructure.