An authentication system is described for controlling a person's access to
a resource, which may be a physical resource or a network resource. The
authentication system obtains credential information for the person
(e.g., using a coded card or keypad for username and password), a voice
print from the person, and the current geographical location of the user.
The voice print and geographic location are preferably obtained from a
telephone call that occurs between the person and the authentication
system. The call can take the form of a cell phone call placed by the
person to the authentication system. The authentication system includes a
user profile database. If the credential information and voice print
match those of persons authorized to access the resource, and the user is
at a registered permissible location to access the resource, the
authentication system sends a signal to the resource indicating that the
authentication was successful.