Method and apparatus for personal identification

#This invention relates to methods and apparatus for identifying an individual and more particularly to methods and apparatus for providing improved security for a personal identification number (PIN) utilized in conjunction with such an identification system.

#Personal identification systems may be based on something someone has, such as a card or badge, something that someone knows, such as a PIN, or some characteristic of the individual, such as his fingerprints or speech pattern. Security for such systems is enhanced by utilizing two or more of the above in performing the identification.

#For example, parent Pat. No. 4,720,860, discloses a personal identification system wherein the individual has a card or other small, portable device which contains a microprocessor programmed to utilize a secret algorithm to generate a nonpredictable number from a stored value unique to the individual and a time varying value provided for example by a clock. The nonpredictable value is preferably displayed on the device. The individual then enters his secret PIN into a central verification system, either directly or over a telephone line, causing the central system to access stored information corresponding to the individual and to utilize at least some of this information to generate a nonpredictable value at the central computer utilizing the same algorithm as at the individual's microprocessor. At the same time this is being done, the individual is entering the number appearing at that period of time on the display of his device. The two values will match, signifying identification of the individual, only if the individual has entered the correct PIN and if the individual has the proper device so that the nonpredictable code displayed corresponds to that being generated at the central verification computer.

#FIG. 1 is a semi-block schematic diagram of the verification system of a first embodiment of the invention.

#FIG. 2 is a block schematic diagram of a second embodiment of the invention.

#FIG. 3 is a block flow diagram illustrating the operation of the first embodiment of the invention and alternative steps for the second embodiment of the invention.

#FIG. 1 shows illustrative structure for a personal identification system of a first embodiment of the invention. In this figure, a user verification device 10 is provided which is of the type described in the parent applications. The device is preferably of the general size and shape of a standard credit card, although its thickness dimension may be slightly greater than that of such cards. The device 10 has a clock which generates a time-dependent digital output to a microprocessor which is programmed with a unique algorithm to operate on the time-dependent clock input and on a stored static value unique to a given user to generate a multi-bit nonpredictable code. A plurality of input areas 12 are provided on the face of device 10. These areas are preferably each indicative of a numerical digit, for example the digits 1-0 as shown in FIG. 1, and may be pressure-sensitive pads or otherwise adapted to generate an electrical output indicative of the area when the area is touched by the user. Spacing may be provided between the individual areas 12 to assure distinctive outputs. As will be described in greater detail hereinafter, the user may input his unique PIN on areas 12 which are mixed in the processor in device 10 with the nonpredictable code generated therein in response to the time-dependent and static inputs to generate a multi-bit nonpredictable code which is displayed on area 14 of device 10. Area 14 may be a liquid crystal display or other suitable display device for producing numeric or alpha-numeric characters. Each area of display 14 is adapted to display a different digit of the nonpredictable code.

#The user initially transmits a nonsecret identifying code to verification computer 16 by keying this number into a telephone 18 at his location. This number is transmitted over telephone lines 20 to telephone 22 at the verification station and through a modem 24 at this station to the verification computer. The user may then use the telephone 18 to key in and transmit the nonpredictable code being displayed at that time on display

#FIG. 3 is a flow diagram illustrating in greater detail the operation of the system of FIG. 1 to perform a verification operation. Referring to FIG. 3, the first step in the operation, step 30, is for the user to send his nonsecret code to verification computer (VC) 16. As previously indicated, this is accomplished by the user keying his nonsecret identification number into telephone 18 for transmission through telephone line 20, telephone 22 and modem 24 to the verification computer.