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CompTIA Linux+ XK0-006 · Domain 3: Security

Cryptography: hashing (sha256sum), GPG signatures, TLS certificates, LUKS disk encryption

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Last reviewed September 30, 2026 · Leer en español

Cryptography gives Linux administrators three practical guarantees: integrity (the data was not changed), authenticity (it came from who you think) and confidentiality (only authorized parties can read it). Linux+ focuses on everyday tools that provide them: hashes for integrity, signatures for authenticity, TLS for data in transit and LUKS for data at rest. Knowing which tool gives which guarantee answers many exam questions on its own.

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