Air Gap

An air gap is a security measure where a computer or network is physically isolated from unsecured networks, including the internet. Air-gapped systems have no wired or wireless connections to outside networks, making remote attacks extremely difficult. Air gaps are used to protect the most sensitive systems and data.

While air gaps provide strong protection against remote attacks, they're not impervious — removable media, supply chain attacks, and sophisticated techniques can potentially bridge air gaps. Air-gapped systems also create operational challenges for updates, data transfer, and system management.