O In a first-party authentication system, when a user
takes an action that requires authentication, they are first
taken to the authentication system component. In this
component they are challenged to provide their identity, and
they provide a response to that challenge. If they fail the
challenge, the system composes a response notifying them of
failure. If they succeed, the system composes a success
response, which is often the resource they requested with their
initial action.