Transport Layer Security (TLS)

TLS encrypts data in transit and authenticates endpoints (commonly HTTPS).

Updated: 2026-03-05

Definition

TLS provides confidentiality and integrity for data in transit, commonly used by HTTPS.

It uses asymmetric cryptography for handshake/key exchange and symmetric encryption for bulk data transfer.

Key points

Protects data in transit
Uses certificates for server authentication
Modern best practice: disable old versions and weak ciphers

Common mistakes

Confusing TLS with encryption at rest (it’s in transit).
Using outdated protocols/ciphers due to legacy compatibility.

Related exams

CompTIA Security+ (SY0-701)

Free Security+ SY0-701 mini test. Continue in the app for offline packs and detailed explanations.

CompTIA Network+ (N10-009)

Free Network+ N10-009 mini test. Continue in the app for offline packs and detailed explanations.

Related terms

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