air gap
To physically separate or isolate a system from other systems or networks (verb).
Senses
Sense 1
To physically separate or isolate a system from other systems or networks (verb).
The physical separation or isolation of a system from other systems or networks (noun).
- NICCS (CISA) Cybersecurity VocabularyJan 06, 2026NICCS glossary export (CSV)https://niccs.cisa.gov/rest/vocab/export-csvNICCS is a CISA (DHS) program. Individual glossary entries include a "From" attribution (e.g., CNSSI 4009, NIST SPs, NICE Framework). Treat "From" values as upstream provenance and verify before quoting large portions of text.Source: NICCS (CISA) Cybersecurity Vocabulary (niccs.cisa.gov).
(I)
An interface between two systems at which (a) they are not connected physically and (b) any logical connection is not automated (i.e., data is transferred through the interface only manually, under human control). (See: sneaker net. Compare: gateway.)
Example: Computer A and computer B are on opposite sides of a room. To move data from A to B, a person carries a disk across the room. If A and B operate in different security domains, then moving data across the air gap may involve an upgrade or downgrade operation.
- IETF RFC 4949 (Internet Security Glossary)Jan 06, 2026RFC 4949 — Internet Security Glossary (Version 2)https://www.rfc-editor.org/rfc/rfc4949.txtRFC 4949 is published by the IETF Trust and marked as "Distribution of this memo is unlimited". Verify IETF Trust copyright/licensing terms for reuse.Source: IETF RFC 4949 (rfc-editor.org).