Method of providing secure user access

• US 6,160,903 A
• Filed: 04/24/1998
• Issued: 12/12/2000
• Est. Priority Date: 04/24/1998
• Status: Expired due to Term

• Current Assignee: Activcard Ireland, Limited
• Original Assignee: DEW Engineering and Development Limited (Trelleborg AB)
• Inventors: Hillhouse, Robert D., Hamid, Laurence
• Primary Examiner(s): Couso, Jose L.
• Assistant Examiner(s): CAGE, SHAWN B
• Application Number:
  US09/065,523
• Time in Patent Office: 963 Days
• Field of Search: 382/115-118, 382/124-127, 382/159, 382/155, 380/23, 704/275, 704/273, 704/270, 340/825.31, 902/3, 235/380, 235/381, 235/382, 235/382.5, 235/379
• US Class Current: 382/115
• CPC Class Codes: G07C 9/37 using biometric data, e.g. fingerprints, iris scans or voice recognition

Abstract

A method of providing secure user access for doorways and network computer systems is disclosed. An overall system security level is provided. A user provides biometric information that is compared against stored biometric information of each of a plurality of users to identify the individual. When the likelihood of a match is above the likelihood necessary for identification, the threshold for that user is increased. Optionally, a threshold for another user is lowered in order to maintain a same system security level. When biometric information provided to the system is consistent, the stored template is automatically updated.

Claims

1. A method of performing one of authorising individuals and identifying individuals using a biometric security system comprising the steps of:

storing a system security level;

determining an initial security level for a plurality of individuals, the initial security level determined such that the actual security level of the system is at least the stored system security level;

storing a current security level in association with at least one of an identification of an individual and an authorisation of an individual;

performing at least one of authorising individuals and identifying individuals using the biometric security system to determine a likelihood that the individual is accurately authorised or identified;

determining individuals who are consistently authorised or identified, the likelihood indicative of a higher level of security than the current security level associated with said individuals;

increasing the current security level associated with the determined individuals;

determining individuals who are consistently authorised or identified identified, the likelihood indicative of a lower level of security than the current security level associated with said individuals; and

,

lowering the current security level associated with the determined individuals such that the resulting actual system security level is at least the stored system security level.

2. In a system comprising means for storing a plurality of biometric templates, each biometric template associated with an identity and a security level, some of the biometric templates associated with different security levels, a method of identifying an individual from a plurality of enrolled individuals comprising the steps of:

receiving biometric information from the individual and providing biometric data based on the biometric information;

comparing the biometric data to some templates from the plurality of biometric templates to determine a likelihood that a first template from the plurality of templates and the biometric data match;

retrieving the associated security level associated with the first template;

when the likelihood is indicative of a match with a level of security at least the associated security level, identifying the individual;

storing the determined likelihood in association with the first template;

retrieving a previously determined likelihood associated with the first template; and

,

increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are indicative of matches with security levels substantially above the security level associated with the first template.

3. A method as defined in claim 2 comprising the steps of:

storing a system security level;

storing the determined likelihood in association with the first template;

retrieving a previously determined likelihood associated with the first template;

increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are indicative of matches having security levels substantially above the security level associated with the first template; and

,

reducing the security level associated with another template from the plurality of templates to maintain the overall system security level at approximately the stored system security level.

4. A method as defined in claim 2 comprising the steps of:

storing the determined likelihood in association with the first template;

comparing the determined likelihood and a previously determined likelihood associated with the first template; and

,

storing a new template as the first template when the previously determined likelihood and the determined likelihood are substantially similar and when the likelihoods are within a first range of values.

5. A method as defined in claim 4 comprising the step of:

increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are substantially similar and when the likelihoods are within the first range of values.

6. A method as defined in claim 2 comprising the steps of:

storing the determined likelihood in association with the first template;

comparing the determined likelihood and a previously determined likelihood associated with the first template; and

,

when the previously determined likelihood and the determined likelihood are substantially similar, prompting the individual to provide authorisation information, receiving the authorisation information from the individual, and storing a new template as the first template when the authorisation information is indicative of user authorisation to store a new template.

7. A method as defined in claim 2 wherein when the likelihood is indicative of a match with a security level less than the associated security level, the method comprises the steps of:

prompting the individual to provide further biometric information;

receiving the further biometric information from the individual and providing further biometric data in dependence thereon;

comparing the further biometric data to a second template from the plurality of biometric templates and associated with the first template to provide a new comparison result;

determining a second likelihood that the biometric data and the further biometric data are from a known individual in dependence upon the previously determined likelihood and the new comparison result;

when the second likelihood is indicative of a security level having at least the associated security level, identifying the individual; and

,

storing data indicative of a difficulty of identifying the individual in association with the first and second templates.

8. A method as defined in claim 7 comprising the steps of:

storing a system security level; and

,

when the actual system security level is better than the stored system security level, lowering a security level associated with templates that are associated with data indicative of substantial difficulty identifying the individual.

9. A method as defined in claim 2 comprising the steps of:

storing a system security level;

maintaining a database of individuals, the individuals divided into two groups--active identified individuals and inactive individuals;

recalculating the actual system security level based only upon security levels associated with the inactive individuals; and

lowering the security level associated with some of the inactive individuals to result in a lower actual security level of at least the stored system security level.

10. A method as defined in claim 9 comprising the step of:

identifying those individuals passing from one group to another and recalculating the actual system security level upon a change to the group of inactive individuals, wherein the security levels of inactive individuals are automatically adjusted to maintain an actual security level of at least the stored security level.

11. In a system comprising means for storing a plurality of biometric templates, each biometric template associated with a security level, some of the biometric templates associated with different security levels, a method of authorising an individual from a plurality of enrolled individuals comprising the steps of:

receiving biometric information from the individual and providing biometric data based on the biometric information;

comparing the biometric data to some templates from the plurality of biometric templates to determine a likelihood that a first template from the plurality of templates and the biometric data match;

retrieving the associated security level associated with the first template;

when the likelihood is indicative of a match with a level of security at least the associated security level, authorising the individual;

storing the determined likelihood in association with the first template;

retrieving a previously determined likelihood associated with the first template; and

,

increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are indicative of matches with security levels substantially above the security level associated with the first template.

12. A method as defined in claim 11 comprising the steps of:

storing a system security level;

storing the determined likelihood in association with the first template;

retrieving a previously determined likelihood associated with the first template;

increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are indicative of matches having security levels substantially above the security level associated with the first template; and

,

reducing the security level associated with another template from the plurality of templates to maintain the overall system security level at approximately the stored system security level.

13. A method as defined in claim 11 wherein when the likelihood is indicative of a match with a security level less than the associated security level, the method comprises the steps of:

prompting the individual to provide further biometric information;

receiving the further biometric information from the individual and providing further biometric data in dependence thereon;

comparing the further biometric data to a second template from the plurality of biometric templates and associated with the first template to provide a new comparison result;

determining a second likelihood that the biometric data and the further biometric data are from a known individual in dependence upon the previously determined likelihood and the new comparison result;

when the second likelihood is indicative of a security level having at least the associated security level, authorising the individual;

calculating the actual security level of the system; and

,

when the calculated actual security level is above a system security level, lowering the associated security level associated with the template such that the actual security level remains above the system security level.

14. A system for performing one of authorising an individual and identifying an individual from a plurality of individuals upon presentation of biometric information of the individual comprising:

means for storing a plurality of biometric templates, each biometric template associated with a security level wherein some templates are associated with different security levels;

means for receiving biometric information from the individual and providing biometric data based on the biometric information;

means comparing the biometric data to some templates from the plurality of biometric templates to determine a likelihood that a first template from the plurality of templates and the biometric data match;

means retrieving the associated security level associated with the first template;

means for performing at least one of identifying the individual and authorising the individual when the likelihood is indicative of a match with a level of security at least the associated security level;

means for storing the determined likelihood in association with the first template;

means for retrieving a previously determined likelihood associated with the first template; and

,

means for increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are indicative of matches with security levels substantially above the security level associated with the first template.

15. A system as defined in claim 14 comprising:

means for storing a system security level;

means for storing the determined likelihood in association with the first template;

means for retrieving a previously determined likelihood associated with the first template;

means for increasing the security level associated with the first template when the previously determined likelihood and the determined likelihood are indicative of matches having security levels substantially above the security level associated with the first template; and

,

means for reducing the security level associated with another template from the plurality of templates to maintain the overall system security level at approximately the stored system security level.

16. A system as defined in claim 14 comprising:

means for storing a system security level;

means for maintaining a database of individuals, the individuals divided into two groups--active identified individuals and inactive individuals;

means for recalculating the actual system security level based only upon security levels associated with the inactive individuals; and

means for lowering the security level associated with some of the inactive individuals to result in a lower actual security level of at least the stored system security level, when the calculated actual security level is substantially above the system security level.