Authentication

Authentication: VerificationVerificationConfirmation that a requirement was met or a remediation achieved its intended result. of the claimed identity of a user or system. The term is central to identity and access controls. In practice, clear guidelines, loggingLoggingThe recording of security-relevant events so activity can be monitored, investigated, and audited., regular review, and the strongest possible authentication are crucial.

How it works and where it fits

Authentication separates the subject, digital identity, authentication factor, and authorization decision. Authentication establishes who or what is presenting an identity; authorization then determines which action is permitted in the current context. Session state, device trust, request origin, and risk signals can further influence that decision.

Practical security relevance

Effective implementation requires a controlled identity lifecycle from creation through role and entitlement changes to suspension and removal. Strong authentication, least privilege, periodic recertification, and traceable logs are central. Controls must also identify abuse of legitimate accounts, because valid credentials alone do not prove that an action is legitimate.

Related concepts

• AuthorizationAuthorizationDecision regarding which actions an authenticated identity is permitted to perform.: Decision regarding which actions an authenticated identity is permitted to perform.
• Multi-Factor AuthenticationMulti-Factor AuthenticationRequires at least two independent factors for identity verification.: Requires at least two independent factors for identity verification.
• Identity ProviderIdentity ProviderA service that authenticates identities and transmits identity information to applications.: A service that authenticates identities and transmits identity information to applications.
• Passwordless AuthenticationPasswordless AuthenticationAuthentication that does not rely on a shared password, such as through passkeys or hardware tokens.: Authentication that does not rely on a shared password, such as through passkeys or hardware tokens.