What is the function of multi-factor authentication (MFA)?

Multi-factor authentication (MFA) serves the critical function of requiring multiple verification factors before granting access to a system or application. This additional layer of security significantly increases the defense against unauthorized access compared to a single-factor authentication system, which typically relies solely on a password.

The essence of MFA lies in its combination of different types of authentication factors. These typically include something the user knows (like a password), something the user has (such as a smartphone or security token), and something the user is (biometrics, such as fingerprint or facial recognition). By requiring a combination of these factors, MFA substantially reduces the likelihood of breaches caused by compromised passwords alone.

In contrast, other options do not accurately describe the purpose of MFA. Enhancing hardware performance or simplifying password recovery does not pertain to security measures. Allowing remote access to all users lacks the necessary security focus inherent in the multi-factor approach, which specifically aims to control and limit access based on verified identities. Thus, the function of MFA is best captured by its requirement for multiple verification factors to ensure secure access.