# Physical air gap

A physical air gap means the signing environment has zero network connectivity: no cables, no wireless, no indirect connection. Transactions move in and out by manual transfer on encrypted, FIPS-certified USB media, eliminating the entire class of network-based attacks against the HSMs holding the keys.

## Operating custody with zero connectivity

Signing requests are exported to encrypted media, carried to the isolated room under dual control, verified and signed inside, and the signature carried back. Quorum approvals with offline signing tokens govern every step, and each transfer is logged and reconciled.

Taurus deploys physical air gap cold storage in production under some of the strictest virtual asset custody frameworks, alongside the technical air gap mode on one platform.

FAQ:

- How long does signing take in a physical air gap? Minutes to hours depending on the institution's ceremony design, not days. The deliberate friction is the point: it guarantees human control over the deepest reserves while the technical air gap tier handles time-sensitive flows.

Related: https://www.taurushq.com/security/air-gapped-custody/ https://www.taurushq.com/glossary/technical-air-gap/ https://www.taurushq.com/glossary/cold-storage/

Learn more: https://www.taurushq.com/glossary/physical-air-gap/