Asset visibility is the ability to discover, identify, and continuously track devices, software, and communications across a network. In practice, it answers basic but critical questions: What is connected? What is it running? Who is it talking to? In IT and especially OT environments, that inventory is often incomplete because of legacy systems, shadow devices, and limited documentation.
It matters because defenders cannot protect what they cannot see. Asset visibility supports vulnerability management, network segmentation, remote-access control, and incident response by exposing unknown or unmanaged assets. Attackers also benefit from poor visibility, using hidden endpoints, rogue services, or unusual communications to persist and move laterally. Security tools for CPS and OT often focus first on passive discovery so they can map assets without disrupting fragile operations. A strong visibility program turns an anonymous network into a managed environment, making anomalies easier to spot and risky change easier to control.