2FaktorAuthentifizierung

2FaktorAuthent... commonly refers to two-factor authentication (2FA), an access control method that requires users to present two distinct types of evidence before granting access. Typically combined with a password (something the user knows), 2FA adds a second factor drawn from something the user has (a token or device) or something the user is (biometric data). The goal is to reduce the risk of account compromise when one factor is stolen or guessed.

Common implementations include time-based one-time passwords (TOTP) generated by authenticator apps, SMS-delivered codes, push notifications, hardware tokens (such as U2F or FIDO2 security keys), and biometric verification on a registered device. Many services support multiple methods and offer account recovery options to address lost devices.

Benefits of 2FA include stronger protection against phishing, credential stuffing, and brute-force attacks. However, not all 2FA methods are equally secure: SMS-based codes are vulnerable to SIM swapping and interception, while poorly implemented push or backup procedures can create new attack vectors. User convenience, cost, and enterprise integration also affect adoption.

Best practices prioritize phishing-resistant standards (FIDO2/U2F), secure enrollment and recovery processes, and fallback options that do not undermine overall security. Organizations should combine 2FA with risk-based authentication policies, user education, and regular reviews of authentication flows to balance security and usability.