DUO Multi-factor Authentication MFA

Multi-factor authentication: Duo adds a second factor to logins so that a password alone is never sufficient, requiring the user to prove possession of a trusted device before access is granted and thereby neutralizing the impact of stolen credentials.

Push notification approval (Duo Mobile app): The Duo Mobile app receives a push notification that the user approves or denies with a single tap, providing a fast, user-friendly verification that confirms the user holds their enrolled device.

One-time passcode generation (TOTP): The Duo Mobile app can generate time-based one-time passcodes that the user enters to authenticate, allowing verification even when the device lacks network or push connectivity.

SMS passcode delivery: Duo can send one-time passcodes by text message as an alternative verification method for users who prefer or require SMS-based codes.

Phone call verification: The service can place an automated callback to the user's phone, which the user answers and acknowledges to approve the login, offering an out-of-band factor for users without the app.