OpenID is described as which in the context of authentication protocols?

• A. Shibboleth
• B. OpenID
• C. PEAP
• D. JSON Web Token

Answer: (B)

OpenID is an authentication protocol that lets users prove their identity to multiple websites by using a trusted identity provider. In practice, you sign in with the identity provider, the site redirects you there to authenticate, and then the provider returns an assertion confirming your identity to the site so you can access it. This is what enables single sign-on across different services.

Other options represent different concepts: Shibboleth is a federated identity system that uses SAML for SSO, PEAP is a wireless network authentication method, and JSON Web Token is a token format used to carry claims—not by itself a full authentication protocol.