RFID rag and method of user verification

An identification tag ( 100 ) facilitates use of a secure computer system ( 300 ). The tag ( 100 ) is adapted to be worn on a user's wrist and includes an identification and registration circuit ( 102 ) that includes an identification component ( 106 ), an affiliation component ( 110 ), and a light-emitting diode ( 112 ). The computer system includes an RF identification tag registration device ( 302 ) operable to acquire user physical information and communicate the physical information to a computer ( 202 ), wherein the computer verifies that a valid user is wearing the tag ( 100 ). The identification and registration device ( 302 ) ensures that the physical information communicated to the computer pertains to the user wearing the tag by comparing pulse signals acquired from the user's hand and wrist as the device ( 302 ) is acquiring physical information. The computer ( 202 ) uses the identification information and the affiliation information to log the user into and out of the system ( 300 ), and to associate the identification information with a particular user.