CIA Triad

The essential security principles of confidentiality, integrity, and availability are often referred to as the CIA Triad. All security controls must address these principles. These three security principles serve as common threads throughout the CISSP CBK. Each domain address these principles in unique ways, so it is important to understand them both in general terms and within each specific domain:

• Confidentiality is the principle that objects are not disclosed to unauthorized subjects.


• Integrity is the principle that objects retain their veracity and are intentionally modified by authorized subjects only.


• Availability is the principle that authorized subjects are granted timely access to objects with sufficient bandwidth to perform the desired interaction.

Different security mechanisms address these three principles in different ways and offer varying degrees of support or application of these principles. Objects must be properly classified and prioritized so proper security access controls can be deployed.