Connected building systems are networked controls for physical facilities, including HVAC, lighting, access control, surveillance, fire alarms, and elevators. They usually run on a mix of IT and operational technology, which means a compromise can affect both data and the physical environment. In cyber security, this matters because these systems often have long lifecycles, vendor remote access, weak segmentation, and default or shared credentials.
Attackers may target them to disrupt operations, lock out occupants, or move from a building network into other corporate systems. Defenders reduce risk by isolating building controls from office networks, enforcing strong authentication, limiting third-party access, patching controllers, and monitoring unusual commands or traffic. In practice, securing connected building systems is part of protecting business continuity, not just devices.