Air gap (networking)

An air gap, air wall or air gapping is a network security measure employed on one or more computers to ensure that a secure computer network is physically isolated from unsecured networks, such as the public Internet or an unsecured local area network. Air gapped computers are commonly used in classified settings where network usage must be limited or cut off completely. In an air gapped setting a flash drive is used to transfer needed external data.

Air Gap (networking) Media

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  An air gapped network (right) with no connection to a nearby internet-connected network (left)