A method of authenticating the identity of a user to determine access to a system includes providing a plurality of factor-based data instances corresponding to a user, evaluating the factor-based data instances to determine if the user's identity is authenticated, and granting or restricting the user's...http://www.google.nl/patents/US6845453?utm_source=gb-gplus-sharePatent US6845453 - Multiple factor-based user identification and authentication
Multiple factor-based user identification and authentication
