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Module 1~9 min

The CIA Triad

Confidentiality, Integrity, and Availability form the foundation of nearly every security decision. This lesson introduces this core model.

What You'll Learn

  • What confidentiality means in security
  • What integrity means in security
  • What availability means in security

Confidentiality and Integrity

Confidentiality means only authorized people can access certain information. Integrity means that information stays accurate and unaltered unless changed by someone authorized to do so.

Availability

Availability means information and systems are accessible to authorized users when they need them. Together, these three principles -- known as the CIA triad -- guide most security decisions.

Example

Encrypting a file protects confidentiality; a checksum that detects tampering protects integrity; and a backup power supply that keeps a server running protects availability.

Key Concepts

ConfidentialityIntegrityAvailability

Key Takeaways

  • Confidentiality keeps information accessible only to authorized people
  • Integrity keeps information accurate and unaltered
  • Availability keeps systems accessible when authorized users need them

Knowledge Check

Which principle is concerned with keeping information accurate and unaltered?

Which principle is concerned with keeping information accurate and unaltered?