Convection is heat transfer through the movement of a fluid, usually air. Warm air becomes less dense, rises, and carries heat away from components; cooler air replaces it. In computing hardware, convection is a core part of how enclosures, heat sinks, vents, and fans remove heat from processors, storage, and security devices.
In cyber security, convection matters because temperature affects reliability and availability. A poorly ventilated firewall, sensor, or fanless endpoint can overheat, throttle, crash, or age faster, weakening defenses and creating downtime. Attackers may try to stress thermal limits with sustained workloads or environmental manipulation, while defenders design cases and racks to improve airflow and natural convection. Good thermal design helps keep secure systems stable under load.