Patent Publication Number: US-9894064-B2

Title: Biometric authentication

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 13/886,299 filed May 3, 2013 and since issued as U.S. Pat. No. 9,426,150, which is a continuation of U.S. application Ser. No. 11/274,266 filed Nov. 16, 2005 and since issued as U.S. Pat. No. 8,458,465, with both applications incorporated herein by reference in their entireties. 
    
    
     BACKGROUND 
     Determining identity of an individual is often required to ensure that transaction between parties may be protected. Thus, technology is required to provide authentication for use in transactions. 
     SUMMARY 
     A biometric authentication system is disclosed that provides a trusted third party biometric authentication capability for independent confirmation of identity of individuals. The biometric authentication system may include a biometric authenticator that has a repository of biometric templates for registered individuals. Thus, when registered individuals are engaged in transactions, their identities may be confirmed by comparing their biometric data with biometric templates stored in the repository. A single set of biometric templates may be used to confirm identities for transactions with any number of organizations. 
     For example, when traveling, a registered party may desire to cash a personal check in a foreign country. A foreign bank may request from the registered party biometric data such as a retina scan, a fingerprint, a facial scan, an ear scan, etc. The captured biometric data together with an identification such as a name or a social security number or its equivalent, for example, may be transmitted to the biometric authenticator. The biometric authenticator may compare the received biometric data with biometric templates corresponding to the identified person. If a match is obtained, then the biometric authenticator may return an authentication certificate to the bank so that bank may be confident that the party is not an imposter and can proceed to cash the check after verifying that sufficient funds are in the checking account, for example. 
     Biometric templates may be trained by capturing biometric data from registering parties during registration using biometric data capture devices such as retina scanners, fingerprint recorders, camera&#39;s, microphones, ear scanners, DNA profilers, etc. A template may be a pattern, a model, etc., that is trained using biometric data such as ones obtained during registration and may be used to verify authenticity of received biometric data during authentication. Templates may be stored in the repository of the biometric authenticator so that upon request, the templates may be used to authenticate a party by comparing supplied biometric data against the biometric templates. 
     Security may be increased by using text-independent speaker verification (SV) where a party is requested to speak a phrase that may be unique for each authentication event to generate an audio input, for example. The audio input may be digitized into a voice print and features of the voice print may be extracted and compared against a stored voice print template. Additionally, a voice print may be converted into an audio signal for authentication by comparing samples of a party&#39;s recorded speech against the audio signal provided by a party when speaking a phrase. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is described in detail with reference to the following figures, wherein like numerals reference like elements, and wherein: 
         FIG. 1  shows an exemplary diagram of a third party biometric authentication system; 
         FIG. 2  shows an exemplary system for capturing biometric data; 
         FIG. 3  shows an exemplary data structure in a repository for biometric data; 
         FIG. 4  shows an exemplary table of group identities; 
         FIG. 5  shows an exemplary block diagram of a biometric authenticator; 
         FIG. 6  shows a flowchart of an exemplary process for authenticating an identity of a party; and 
         FIG. 7  shows a flowchart of an exemplary process for registering first parties. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       FIG. 1  shows an exemplary block diagram of a trusted third party biometric authentication system  100  that may include first party systems  104 - 106 , second party systems  108 - 110 , and a biometric authenticator  112  that maintains a repository  114 . All of these components may be coupled via network  102 . Network  102  may be any combination of networks such as internets, local area networks (LANs), wide area networks (WANs), wireless, wired, optical, etc. Biometric authenticator  112  may be a trusted independent party providing biometric authentication services to first and second parties  104 ,  106  and  108 ,  110 , respectively. Second party systems  108  and  110  may be operated by various business entities, for example, such as a bank, a credit card company, a vendor, etc., that may engage in transactions with first parties operating first party systems  104 - 106 , or immediately with first parties without the use of first party systems  104 - 106 . 
     For example, a first party using first party system  104  may be engaged in an online banking transaction such as paying a bill with a bank that is using second party system  108 . Before completing the transaction, second party system  108  may request biometric data from first party system  104  to confirm the identity of the first party. First party system  104  may issue a request to the first party for one or more of a retina scan, a fingerprint, a facial image, an ear scan, etc., using biometric data capture devices that may be coupled to first party system  104 . After receiving the requested biometric data, first party system  104  may transmit the received biometric data to second party system  108  for authentication. Second party system  108  may request biometric templates from biometric authenticator  112  and perform the authentication process or forward the biometric data to biometric authenticator  112  for authentication. Alternatively instead of sending the biometric data to second party system  108 , first party system  104  may be instructed to send the biometric data directly to biometric authenticator  112  for authentication. 
     A request for authentication and associated biometric data may be received with a claimed identification of a first party. Biometric authenticator  112  may use the claimed identity to search repository  114  for biometric templates belonging to that first party. Biometric data may not exactly match biometric templates. Thus, one or more thresholds may be established so that a confidence level may be established based on biometric data/biometric template(s) comparison(s). Biometric authenticator  112  may provide either an authentication certificate when comparison results exceed appropriate thresholds sufficiently to declare a “match,” and/or a confidence score so that the second party may determine whether or not the authentication is successful. The second party may, for example, request additional biometric data possibility to increase the confidence score to a desired value. If an acceptable confidence score has been achieved, then the second party may choose to complete the associated transaction. 
     If the second party desires to perform the authentication process and requests one or more biometric templates for an identified party, biometric authenticator  112  may retrieve corresponding biometric templates based on the claimed identity of that parry, and transmit the biometric templates to second party system  108 . In this way, second party system  108  may use its own matching techniques so that desired confidence levels may be obtained. 
     Text-independent speaker verification also may be used as a form of biometric authentication. For example, second party system  108  or biometric authenticator  112  may request the first party to speak a provided phrase to generate an audio signal. The audio signal received by a microphone of first party system  104  may be digitized into a voice print. Features extracted from the voice print may be transmitted to second party system  108  or to biometric authenticator  112  for comparison against appropriate templates. The voice print may also be transmitted and converted into an audio signal and output for audio confirmation by an operator in addition to automated authentication. 
     Biometric authenticator  112  may provide a first party identification based on provided biometric data as well as authenticate an identity of a first party based on the provided biometric data. For example, second party system  108  may send biometric data without also providing a corresponding claimed identity. Biometric authenticator  112  may search repository  114  for biometric templates that match the provided biometric data and return one or more identities that may correspond to the provided biometric data. 
     Repository  114  may provide a grouping of the biometric templates. Second party system  108  may send biometric data along with a group identifier. Biometric authenticator  112  may restrict the search for matching biometric templates only within the identified group, thus reducing a number of false positive identities. For example, a family might all use the same voicemail account, but have separate mail boxes. The voicemail system may obtain biometric data by requiring a first party accessing the voicemail to speak a pass phrase. When speech for the pass phrase is received as the biometric data, the voicemail system may send the biometric data along with an identifier for the family voicemail identified by the family name, for example. Biometric authenticator may restrict the search only to voice templates among those belonging to the family. Biometric authenticator may return an individual identity and a confidence score to the voicemail system for determination of whether to provide access to a correct mail box. 
     The phrase used in speaker verification may be generated by either the second party or biometric authenticator  112  in a manner that would make it difficult to predict its contents. The phrase may be generated from a large corpus of phrases, a source of random words, or spontaneously from a prior communication, for example. The generated phrases or words may be saved for each first party in repository  114  either for later use or for guaranteeing that the phrases are not used again. Instead of saving the used phrases or words, they may be deleted to avoid copying by imposters. 
     In view of the above, trusted third party biometric authenticator  112  may maintain security of repository  114 , provide uniform and cost effective authentication services and relieve first and second parties of security tasks. For example, second parties are not required to maintain voice security for their services on their site or platforms and first parties are relieved of maintaining security of individual devices such as PDAs and laptops. Additionally, first parties may need to provide biometric data once for training templates and thus avoid template training process for every vendor that they deal with. 
     While the above discussion is based on an online banking example, other types of transactions may also take advantage of services of a biometric authenticator  112 . For example, when engaged in an online purchase, a vendor may request biometric data from a prospective purchaser and request authentication of the prospective purchaser&#39;s identity in connection with a credit card. Biometric authenticator  112  may provide confirmation that the prospective purchaser is an authorized user of the credit card, for example. Additionally, the first party may not be using first party system  104 . Instead, the first party may be physically at a second party facility engaged in a transaction with the second party. Prior to completing the transaction, the second party may request the first party to provide biometric data using biometric data recorders at the second party facility, for example. The transaction between the first and second parties may be completed upon successful authentication either by biometric authenticator  112  or by the second party using templates provided by biometric authenticator  112 . 
       FIG. 2  shows an exemplary end-user system  200  that includes a control processor  202 , a display  204 , a keyboard  206 , a mouse  208 , speakers  210 , a camera  212 , a microphone  214 , a retina scanner  216  and a fingerprint recorder  218 . While  FIG. 2  shows that the end-user system  200  includes many different types of biometric data capture devices,  212 - 218 , an end-user system may include any combination of one or more of these biometric capture devices  212 - 218  as well as other types of biometric data capture devices such as DNA profiler, ear scanner, etc. For example, end-user system  200  may include only microphone  214  to receive an audio input so that control processor  202  may generate a voice print. Also, biometric data capture devices  212 - 218  may be combined into a single device that is capable of capturing all types of the above-mentioned and other biometric data. 
     Additionally, while  FIG. 2  shows biometric data capture devices  212 - 218  connected directly to control processor  202 , they may be connected indirectly via a network such as network  102 , for example. The biometric data capture devices  212 - 218  may be physically disposed in a remote location relative to controller processor  202 . Also, end-user system  200  may represent first party systems  104 - 106 , second party systems  108 - 110  or biometric authenticator  112 . For example, if end-user system  200  represents first party system  104 , then such a system may include only camera  212  and microphone  214  as biometric data capture devices. A first party may operate end-user system  200  using keyboard  206  and mouse  208  and input biometric data such as speech input via microphone  214  and facial image or ear scan via camera  212 . 
     If end-user system  200  represents second party system  108 , for example, then biometric data capture devices  212 - 218  may not be included at all and end-user system  200  may include only programs for requesting biometric data from first parties and biometric templates from biometric authenticator  112  and perform the authentication process. If authentication is performed by biometric authenticator  112 , end-user system  200  may only include programs for interfacing with first parties and biometric authenticator  112 . 
     Alternatively, second party systems  108 - 110  may include party registration facilities that provide biometric data capture devices for capturing biometric data from registering parties. For example, biometric capture devices  212 - 218  may be located in a specified area where registered parties may be instructed to provide their biometric data as part of a registration process. The data captured in this manner may be provided to biometric authenticator  112  for creation and storage of templates for future authentication processes. First parties may also perform the registration process using first party systems  104 - 106  that may collect biometric data as part of a service provided by a second party and/or the biometric authenticator  112 . 
     If end-user system  200  represents biometric authenticator  112 , then control processor  202  may be capable of high volume processing so that many different second party systems  108 - 110  may be supported. Biometric data capture devices  212 - 218  may be located in party registration facilities so that potential first parties may be registered with biometric authenticator  112  in addition to registration facilities that may be provided by second parties; as noted above. 
     Control processor  202  may be coupled to a mass storage device that serves as memory for repository  114 . For example,  FIG. 3  shows an exemplary data structure  240  for repository  114  that may include records  242 - 246  corresponding to each registered party, for example. Each of the records  242 - 246  may include an identification field  248 , multiple biometric data entries  252  where each biometric data entry may include multiple fields  250 . For example, record  242  may include entries for a retina scan, a fingerprint, a facial image, a voice print, etc. For example, fields  250  may include information such as a copy of actual biometric data, recordation date/time corresponding to the biometric data, a biometric template for each type of biometric data that may be generated via a training process during registration, etc. 
       FIG. 4  shows an exemplary table that may be indexed according to group identities. For example,  FIG. 4  shows group identities n, n+1, . . . , n+p grouping groups m1, m2, . . . , mp first parties together, respectively. Pointers to records of the identified first parties form entries in the table so that biometric authenticator  112  may easily access biometric templates for each of the identified first parties when searching for a match to provided biometric data. Thus, when a second party requests retrieval of an identification for a provided biometric data for a particular group identity, biometric authenticator  112  may limit its search for a matching biometric template to only those identifications identified by the table under the provided group identity. Similarly, the second party may provide a claimed identity and a group identity so that biometric authenticator may determine whether the identity is included within the provided group identity even without performing biometric comparison between provided biometric data and biometric templates. 
     The above-discussed biometric data entries and corresponding fields are examples only. Other different types of biometric data and fields may be added, or only a subset of the above-discussed biometric entries  252  and fields  250  may be used. Also, while  FIG. 3  shows biometric data stored in a table-like manner, other database structures may be used such as relational databases having indices, link lists, etc. Sophisticated database structures may be used in biometric authenticator  112  because a relatively large volume of biometric data may be stored. 
     The recordation date/time field of each biometric data entry may provide an indication of the age of the biometric data. Depending on the type of biometric data, such as facial image, a time limit may be set for updating the biometric data. For example, when an elapsed time threshold is exceeded, biometric authenticator  112  may issue requests for updates of biometric information or biometric data may be requested on a next opportunity when the associated registered party is engaged in a transaction, for example. Other adaptation schemes may also be used to update and improve the biometric templates such as using a difference between the received biometric data and a centroid of clusters in the biometric templates as a trigger to incorporate the received biometric data, for example. 
       FIG. 5  shows an exemplary block diagram of biometric authenticator  112  that may include a controller  262 , a memory  264 , an operator interface  270 , a biometric information comparator  272 , a biometric template generator  274 , and a network interface  266 . Memory  264  may comprise one or more mass storage devices such as ROM, RAM, optical disk(s), hard disk(s), etc. Repository  114  may be stored in memory  264 . Repository  114  may be stored elsewhere but is shown stored in memory  264  for convenience. These components may be coupled by a bus  268 . The comparator and the template generator may be software systems that may run on separate processors or on the same processor. 
     As mentioned above, biometric authenticator  112  may be connected to biometric data capture devices  212 - 218 . The biometric data capture devices  212 - 218  may be either directly coupled to controller  262  via bus  268  or remotely connected (as shown by dashed lines) when biometric data capture devices  212 - 218  are physically disposed in a location remote from controller  262 . Also, many copies of biometric data capture devices  212 - 218  may be provided so that party registration may be efficiently performed with many registering parties. The data capture devices may be part of a first party system  104 - 106 . The first party may be requested to use these devices as part of a registration process operating on a second party system  108 - 110 , or as part of aregistration process operating on biometric authenticator  112 . Further, the data capture devices  212 - 218  may be part of one or more second party systems  108 - 110  and used as part of a registration process. For example, a first party may be using an Automatic Teller Machine (ATM) at a bank for the first time. The ATM may request that the first party provide a finger print or a voice sample for creating a biometric template. 
     While  FIG. 5  shows biometric authenticator  112  using a bus architecture, any type of hardware architecture, including wired and wireless networks, may be used based on implementation details. For example, biometric data capture devices  212 - 218  may be coupled to bus  268  via network interface devices and memory  264 , operator interface  270  and network interface  266  may be individually connected to controller  262 . Also, these hardware components may be implemented using any available hardware technology such as FPGA, PAL, application specific integrated circuits (ASICs), etc. 
     When a request for biometric authentication is received via network interface  266 , controller  262  may retrieve one or more biometric templates and/or data from repository  114  such as from memory  264 , for example. Controller  262  may direct the templates to be sent to biometric information comparator  272  together with the received biometric data. Biometric information comparator  272  may compare the received biometric information (biometric template(s) and/or data) against the one or more retrieved biometric information and determine whether the result of the comparison exceeds one or more thresholds corresponding to confidence levels, for example. Controller  262  may send the confidence level to the requesting second party via network interface  266  and/or an authentication certificate if a highest confidence level has been exceeded. If the comparison result fails to exceed a minimum threshold, for example, then controller  262  may issue an authentication failure message to the requesting second party via network interface  266 . If instead of a request for authentication, biometric authenticator  112  received a request for biometric information, controller  262  may retrieve requested information such as biometric templates from repository  114  and forward the biometric information to the requesting second party via network interface  266 . 
     If a first party desires to register biometric data with a second party, the second party may issue a prompt to the registering first party via a display (not shown), for example, to request the registering first party to provide the biometric data via one or more of biometric data recording devices provided by the second party Once received, the second party may send the collected biometric data to biometric authenticator  112 . When received via network interface  266 , for example, controller  262  may direct the received biometric data to biometric template generator  274  to generate one or more biometric templates. If additional samples of biometric data are required, controller  262  may make a request to the second party to again prompt the registering first party to provide the needed additional biometric data. When all the needed one or more biometric templates are generated, controller  262  may add a new biometric record in repository  114  and record the new biometric template(s) in the created biometric record together with recordation date and time, for example. Alternatively, the second party may transfer control over to biometric authenticator  112  for the complete registration process including interfacing with the registering first party. 
     Repository  114  may be used by many second party systems  108 - 110  for authenticating registered first parties to complete transactions. As noted above, second party systems  108 - 110  may also register first parties and either the biometric data and/or the generated templates may be provided to biometric authenticator  112  for storage in repository  114 . Registered first parties may engage in transactions with many different second parties so that significant overlap may occur among patrons of various second parties. Thus, repository  114  managed by biometric authenticator  112  may provide a cost effective authentication service without requiring first parties to repeat registration processes with multiple second parties. 
     When a second party registers a first party, the collected biometric information together with the identification provided by the first party may be transmitted to biometric authenticator  112 . Biometric authenticator  112  may perform a search of repository  114  to determine whether the biometric information corresponding to the identified party is already in repository  114 . If biometric information is already in repository  114 , biometric authenticator  112  may compare the biometric information retrieved from repository  114  against the newly provided biometric information to determine whether the two sets of biometric information are substantially identical or substantially different. If the two sets of biometric information are substantially identical, biometric authenticator  112  may either store both sets of biometric information or select one of the sets for storage. If the two sets of biometric information are substantially different, then a message to that effect may be returned to the second party who may take various actions such as request additional biometric data, alert authorities for possible security breach, etc. 
     Further, biometric authenticator  112  may search repository  114  to determine whether the newly provided biometric information match biometric information that correspond to an identity that is different than that provided by the registering first party. If one or more matches are found, then a warning may be sent to the second party, for example. In this way, unique correspondence between biometric information and identities may be maintained. 
       FIG. 6  shows a flowchart  300  of an exemplary biometric authenticator process for confirming identity of a first party. In step  302 , the process determines whether a request for authentication is received. If a request is received, the process goes to step  304 ; otherwise, the process returns to step  302 . In step  304 , the process attempts to retrieve from a repository biometric information corresponding to the received identity and goes to step  306 . In step  306 , the process determines whether biometric information corresponding to the received identity is found in the repository  114 . If the biometric information is found, the process goes to step  308 ; otherwise, the process goes to step  312 . 
     In step  308 , the process determines whether the received biometric information matches the retrieved biometric information based on one or more thresholds and goes to step  310 . In step  310 , the process returns to the requesting second party a confidence score corresponding to exceeded thresholds and/or an authentication certificate if a highest threshold was exceeded and goes to step  314 . In step  312 , the process returns a message indicating that information is not available for authentication, and the process goes to step  314 . In step  314 , the process determines whether another request for authentication is received. If another request is received, the process returns to step  304 ; otherwise, the process goes to  316  and ends. 
       FIG. 7  shows a flowchart  400  of an exemplary process for registering a first party. In step  402 , the process prompts the registering first party to provide biometric data via one or more biometric data capture device and goes to step  404 . In step  404 , the process determines whether the requested biometric data has been received. If the requested biometric data has been received, the process goes to step  412 ; otherwise, the process goes to step  406 . In step  406 , the process increments a timer and goes to step  408 . In step  408 , the process determines whether a maximum time has been exceeded. If the maximum time has been exceeded, the process goes to step  410 ; otherwise, the process returns to step  404 . In step  410 , the process issues a registration failed message and goes to step  426  and ends. 
     In step  412 , the process determines whether additional biometric data is required to generate one or more biometric templates. If additional biometric data is required, the process returns to step  402 ; otherwise, the process goes to step  414 . In step  414 , the process generates one or more biometric templates and goes to step  416 . 
     In step  416 , the process determines whether the received biometric data and/or the generated biometric templates (biometric information) are substantially the same as ones that are already in the repository. If substantially the same biometric information is already in the repository, the process goes to step  420 ; otherwise the process goes to step  418 . In step  420 , the process determines whether the identity provided by the registering party is substantially the same as the identity that corresponds to the biometric information already in the repository. If the identities are substantially the same, the process goes to step  422 ; otherwise, the process goes to step  424 . In step  422 , the process resolves the redundancy between the biometric information of the registering party by discarding one of the biometric information or by storing both copies and goes to step  426  and ends. In step  424 , the process generates a discrepancy alert to the biometric authenticator operator, for example, and take appropriate action such as alerting enforcement personnel and goes to step  426  and ends. In step  418 , the process stores the generated biometric information into the repository and goes to step  426  and ends. 
     While the invention has been described in conjunction with exemplary embodiments, these embodiments should be viewed as illustrative, not limiting. Various modifications, substitutes or the like are possible within the spirit and scope of the invention.