Which authentication type can a Citrix Administrator use to enable Citrix ADC AAA dual-factor authentication from a user’s mobile device app?

• A. Ldap
• B. Local
• C. Saml
• D. Radius

Answer: (A)

Dual-factor authentication with Citrix ADC AAA is typically implemented by connecting to an external 2FA provider via RADIUS. LDAP and Local store are just ways to validate credentials against a directory or local database and do not provide a second factor on their own. SAML can enable web-based SSO through an identity provider, and that IdP can enforce 2FA, but for a straightforward mobile-device app-based second factor integrated directly into the ADC flow, using RADIUS to talk to a 2FA server is the standard approach. In practice, the ADC forwards the user’s credentials to the RADIUS server; the server prompts for the second factor via the mobile app (push, OTP, etc.), the user completes the second factor on their device, and the RADIUS server confirms success, allowing access.