UAF20

UAF20 is not a single, universally defined term. In many technical discussions it is used as a shorthand variant of UAF 2.0, or Universal Authentication Framework 2.0, a specification developed by the FIDO Alliance. Because acronyms can be applied differently across organizations, the exact meaning of UAF20 can vary with context, so identifying the domain is important for clarity.

If UAF20 refers to UAF 2.0 in authentication, it describes a passwordless authentication framework intended to enable users to sign in to online services without passwords. It supports methods such as biometrics, security keys, or device-bound credentials. The framework defines a registration flow, where the user’s device creates a public-key credential bound to the service, and an authentication flow, where a challenge is signed with the corresponding private key. Attestation and user verification are part of the specification. UAF 2.0 is part of the broader FIDO ecosystem and predates the FIDO2/WebAuthn approach; many ecosystems have shifted toward WebAuthn, but some platforms still implement UAF 2.0 or use it in hybrid forms.

In other domains, UAF20 could denote a version or variant of a framework or architecture with the initials UAF, such as a Unified Architecture Framework 2.0 used in software or enterprise architecture. Because UAF is an acronym used by multiple organizations, a precise definition requires domain-specific context or a clarifying specification. See also: FIDO Alliance, UAF 2.0, WebAuthn, FIDO2.