CTAPFIDO2

CTAPFIDO2 refers to a set of standards developed by the FIDO Alliance that enable passwordless authentication. CTAP stands for Client to Authenticator Protocol, and FIDO2 is a trademark for the combined FIDO Alliance's WebAuthn standard and the CTAP protocol. This technology allows users to authenticate to online services using hardware security keys, biometric scanners, or other secure authenticators instead of traditional passwords. The FIDO2 framework aims to enhance security and improve user experience by eliminating the vulnerabilities associated with passwords, such as phishing and weak password practices.

The core components of FIDO2 are the WebAuthn specification, which defines a standard API for web browsers and applications to interact with authenticators, and the CTAP protocol, which specifies how clients (like browsers) communicate with external authenticators (like USB security keys). This layered approach ensures broad compatibility and security across different devices and platforms. When a user registers a FIDO2 authenticator with a service, a unique public and private key pair is generated on the authenticator. The public key is then sent to the service, while the private key remains securely stored on the authenticator and is never revealed. During authentication, the service sends a challenge to the client, which is then signed by the authenticator using the private key. This signature is verified by the service, confirming the user's identity without the need for a password.