Air Gap

An air gap is a security design in which a system has no network connection to untrusted networks, including the internet. Data moves in or out only by controlled physical means, such as approved removable media.

Why it matters

If a system cannot be reached over a network, remote attacks against it become much harder. Air gaps are used for industrial control systems, key signing, classified environments and some backup stores. A disconnected, offline backup is also a defence against ransomware that spreads across connected storage.

Example

A certificate authority keeps its root signing key on a machine in a locked room with no network card enabled. To sign a new intermediate certificate, staff carry a scanned request on a checked USB drive to the machine, sign it, and carry the result back under a documented procedure.

Common misconceptions

• "Air-gapped means unhackable." Researchers have shown that infected removable media, insiders and even signals such as sound or electromagnetic emissions can bridge gaps.
• "A firewall equals an air gap." A firewall filters connections; an air gap has none.
• "Once isolated, no updates are needed." Offline systems still need patching and controlled media procedures.

Related

• Backup
• Ransomware
• Firewall
• Private key

यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.