Abstract:
An apparatus and a method for generating a unique user identification code for a user of a biometric security system is presented. No biometric information is stored either within the security system or on a device, and process enables a unique user identification code to be generated to allow multi-system identification of the same user. 
     The method includes retrieving a public key from the system, obtaining a characteristic from the user and generating a biometric value from the characteristic, and creating the identification code by combining and encrypting the generated biometric value and the system supplied public key, and transmitting the identification code to the system for authentication.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates generally to biometric security systems. In particular, this invention relates to a method of using the same biometric information as identification in one or more security systems without storing the biometric information in any of the security systems. 
       BACKGROUND OF THE INVENTION 
       [0002]    Security systems control access to places and data by requiring those desiring access to be identified and authenticated. Biometric security systems use biometric data, such as a fingerprint, thumbprint, or retina scan, for identification and authentication. Initially the security system registers the user by storing his biometric information. Subsequently, to gain access to the system, the user must present his biometric information to be identified and authorized by the system. The biometric information can be presented, for example, by scanning a finger or thumb or retina, or by presenting a device on which the information has been stored. A variety of products exist which capture fingerprint biometric information and compare it to previously captured biometric information stored in the security system. The stored information resides either in a database on the system&#39;s network, or on a mobile biometric device, such as a smart card, that is carried by the user. Additionally, there are mobile biometric devices that capture the fingerprint biometric information and compare it to biometric information residing on the device, and then transmit a predefined credential identifier to the system in lieu of the biometric information. 
         [0003]    One problem with the above approaches is that, since a user&#39;s biometric information must be stored either within a database in the security system or on a device the user carries, the stored information could be stolen or altered. Another problem is that the information can only be accessed by the specific system that stores the information or the credential identifier, so that the user&#39;s biometric information cannot be shared among various systems to authenticate the user. 
       SUMMARY OF THE INVENTION 
       [0004]    This invention solves the above problems with an apparatus and a method whereby no biometric information is stored either within the security system or on a device, and further provides a method to allow unique multi-system identification. 
         [0005]    Accordingly, the invention provides a method for generating a unique user identification code for a user of a biometric security system, including the steps of receiving a public key from the system, obtaining a characteristic from the user and generating a biometric value from the characteristic, and creating the identification code by combining and encrypting the generated biometric value and the system supplied public key, and transmitting the identification code to the system, and an apparatus to implement this method. 
         [0006]    The foregoing and other objects, aspects, features, advantages of the invention will become more apparent from the following description and from the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The invention is further described in the detailed description that follows, by reference to the noted drawings by way of non-limiting illustrative embodiments of the invention, in which like reference numerals represent similar parts throughout the drawings. As should be understood, however, the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings: 
           [0008]      FIG. 1  is a block diagram of an exemplary embodiment of the present invention; 
           [0009]      FIG. 2  is a flow diagram of the steps for creating and registering a unique identification code in one embodiment of the present invention; and 
           [0010]      FIG. 3  is a flow diagram of the steps for authenticating a user in one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0011]    An inventive solution to the need for security systems able to identify a user based on his biometric data without storing this data, and further enabling this data to be used by more than one security system, is presented. 
         [0012]      FIG. 1  shows an exemplary embodiment of the invention. A security system  10  can secure a physical location such as an office building, residence or other structure or groups of structures. In addition, a security system  10  can secure access to data, such as credit card databases, bank accounts, and any other collections of data and information to which authorization is required to obtain access. The security system  10  includes a registration station  28 , and a network interface device  12 , each of which broadcasts public key information  14  such as a system ID, and the current date and time. In one embodiment, the network interface device is a smart card RFID reader; however, other RFID readers can be used. While only one registration station  28  is shown, the system can have multiple such stations. Similarly, the system can contain multiple network interface devices, even though only one is shown. A user has an active RF device  16  that includes a microprocessor  18 , flash and RAM memory  20 , and a biometric input unit  22 , such as a fingerprint scanner. In a preferred embodiment, the active RF device  16  is a smart card token. Other devices able to transmit and receive RF data can be used, such as mobile telephones, key fobs and laptop computers. 
         [0013]    To register to become an authorized user of the security system  10 , the user presents the RF device  16  to a registration station  28 . The RF device  16  receives the public key information  14  broadcast by the registration station  28  and the RF device  16  prompts the user to present a physical characteristic or part, such as a finger, thumb, foot or retina, for input, e.g. scanning by the scanner  22 . The result of this input is a biometric value. A unique digital value  24 , derived from the biometric value, of the user&#39;s physical characteristic is created based on this scan. This unique digital value  24  and the system&#39;s public key information  14  are used to encrypt the system ID. The resultant value, a unique identification code  26  for the user, is stored in a database  30  in the security system  10  and can be used later to authenticate the user to the system  10 . In one embodiment, this unique identification code  26  is encrypted. 
         [0014]    To access the security system  10 , a user presents the RF device  16  to the network interface device  12 . The RF device  16  receives the public key information  14  broadcast by the network interface device  12  and the RF device  16  prompts the user for biometric input  22 . As above, a unique digital value  24  is created from the biometric input or biometric value  22 . Using this unique digital value  24  and the system&#39;s public key information  14 , a unique identification code  26  for a user is determined. This unique identification code  26  is encrypted if the initially registered code had been encrypted. The unique identification code  26  is transmitted through the network interface device  12  to the security system  10  where it is authenticated. The authentication process is described in more detail below. 
         [0015]      FIG. 2  shows the steps in an exemplary embodiment for registering a user by creating a unique user identification code  26  in accordance with the system shown in  FIG. 1 . Initially, at step S 1 , a user presents the RF device  16  to a registration station  28  on the network. At step S 2 , the RF device  16  receives the public key information  14  broadcast by the registration station  28 . At step S 3 , the biometric input unit  22  of the RF device  16  obtains a user characteristic, e.g., obtains a fingerprint by scanning the user&#39;s finger. At step S 4 , the fingerprint is converted to digital minutia using a fingerprint template. Other techniques for converting the input data to digital minutia can be used. 
         [0016]    At step S 5 , an algorithm for generating a unique digital value  24  based on the digital minutia is executed. This algorithm could be, for example, a hash-coding algorithm that generates a unique value, i.e., the unique digital value  24 , from a plurality of data, i.e., the digital minutia. Any algorithm that creates a unique data value from a plurality of input data can be used. At step S 6 , an encryption methodology is used to combine the public key information  14  with the unique digital value  24  to create a unique identification code  26 . The encryption methodology can be, for example, a common PKI algorithm to encrypt the unique digital value  24  and the system ID obtained from the public key information  14 , or the entire public key information  14  can be encrypted with the unique digital value  24 . A standard PKI call to encrypt data might look like: Encrypted data=encrypt (public, key, private key, data). In one embodiment of the present invention, the PKI call would look like: Encrypted system ID=encrypt (system public key  14 , unique digital value  24 , system ID). At step S 7 , the unique identification code  26  is transmitted or broadcast via the registration station  28  and stored in a database  30  in the security system  10 . 
         [0017]    Authentication is performed as shown in  FIG. 3  in accordance with the system shown in  FIG. 1 . At step S 8 , user presents the RF device  16  to a network interface device  12 . At step S 9 , the RF device  16  receives the public key information  14  broadcast by the network interface device  12 . At step S 80 , the biometric input unit  22  of the RF device  16  obtains a fingerprint or other physical characteristic of the user. For each user, the same characteristic supplied for registration must be supplied for authorization. At step S 11 , the fingerprint is converted to digital minutia using a fingerprint template, or other known techniques. 
         [0018]    At step S 12 , an algorithm for generating a unique digital value  24  based on the digital minutia is executed. As with the registration process discussed above, this algorithm could be, for example, a hash-coding algorithm that generates a unique value, i.e., the unique digital value  24 , from a plurality of data, i.e., the digital minutia. Any algorithm that creates a unique data value from a plurality of input data can be used. The same algorithm is used for registration and authentication of a particular user, but different algorithms can be used for different users. At step S 13 , an encryption methodology is used to combine the public key information  14  with the unique digital value  24  to create a unique identification code  26 . As with the algorithm, the same encryption methodology is used for registration and authentication for a particular user. At step S 14 , the unique identification code  26  is transmitted or broadcast via the network interface device  28  to the security system  10 . 
         [0019]    At step S 15 , the security system  10  determines whether the unique identification code  26  exists in the database  30 . If the unique identification code  26  matches one in the database  30  (S 15 =YES), the user is authorized to use the security system  10 . However, if the unique identification code  26  does not match any database  30  entries (S 15 =NO), the user is not authorized to use the security system  10 . 
         [0020]    Thus the broadcast public key information  14  of the security system  10  in conjunction with a unique digital value  24  based on the user&#39;s biometric information creates a unique identification code  26  which is calculated by the RF device&#39;s microprocessor  18  each time a user desires access to a security system  10 . This unique identification code  26  is the user&#39;s identification code or authorization code as stored in the security system  10 . The combination of broadcast public key information  14  and unique, individual biometric information as represented in a unique digital value  24  ensures that the unique identification code  26  received from any individual authorized to use the security system  10  is unique to that individual user. Consequently, the same RF device  16  can be used by multiple individuals to authenticate themselves because the RF device  16  produces a unique digital value  24  for each user based on each user&#39;s biometric information, and this unique digital value  24  is then combined with the broadcast public key information  14 . 
         [0021]    In addition, since the unique identification code  26  is calculated each time the RF device  16  is presented, standard user biometric information is not stored either in a network database in the security system  10  or on the RF device  16 . Instead, the standard user biometric information, for example, fingerprint data, is stored only in combination with system identification data, that is, the broadcast public key information  14 , in a system database  30 . Further, this combination data is generally encrypted. Thus the security of the system is enhanced because there is no file of user information or biometric data to be compromised. 
         [0022]    While the present invention has been described in particular embodiments, it should be appreciated that the present invention should not be construed as limited by such embodiments, but rather construed according to the below claims.