Which security principle requires that a system have a high degree of confidence about the identity of the actor performing an action?

Which security principle requires that a system have a high degree of confidence about the identity of the actor performing an action?

• A. Authentication
• B. Non-repudiation
• C. Confidentiality
• D. Availability

Answer: (B)

Authentication is the process of establishing that someone is who they claim to be. When a system has a high degree of confidence about the identity of the actor performing an action, it’s because the authentication step verified their credentials—such as a password, token, biometric factor, or certificate—allowing the system to attribute the action to a specific, verified user. This confidence is essential for deciding whether to grant access and for auditing what actions that user performs. Non-repudiation, by contrast, is about preventing someone from denying that they performed a given action after the fact, typically using digital signatures and tamper-evident logs; it strengthens accountability but does not by itself establish the identity during the action. Therefore, the described principle is authentication.

Authentication is the process of establishing that someone is who they claim to be. When a system has a high degree of confidence about the identity of the actor performing an action, it’s because the authentication step verified their credentials—such as a password, token, biometric factor, or certificate—allowing the system to attribute the action to a specific, verified user. This confidence is essential for deciding whether to grant access and for auditing what actions that user performs. Non-repudiation, by contrast, is about preventing someone from denying that they performed a given action after the fact, typically using digital signatures and tamper-evident logs; it strengthens accountability but does not by itself establish the identity during the action. Therefore, the described principle is authentication.