What is the authentication method that provides secure password-based authentication and relies on forward secrecy?

The authentication method that provides secure password-based authentication while relying on forward secrecy is Simultaneous Authentication of Equals (SAE). SAE is designed to enhance the security of the password-authenticated key exchange process. It achieves this through a mechanism that ensures that even if a password is compromised in the future, past sessions cannot be decrypted.

Forward secrecy is a key property in cryptographic protocols that ensures that session keys are not derived from static keys, or passwords, used in the authentication process. This means that every session generates unique keys, so even if an attacker retrieves one of these keys later, it won't compromise past or future sessions. SAE's use of the password in this dynamic way, along with its resistance to offline dictionary attacks, makes it a robust choice for secure password authentication.

In contrast, the other options either do not specifically refer to password-based authentication or do not incorporate forward secrecy in the same way as SAE. Two-factor authentication, for example, involves the use of an additional method alongside a password for enhanced security but does not inherently provide the forward secrecy characteristic. OAuth 2.0 is an authorization framework rather than a direct authentication method, while Public Key Infrastructure (PKI) relates to using public and private keys for authentication and encryption but