Patent ID: 7522751

Claim:
A method of securely indexing and storing a biometric for subsequent retrieval, the method including: using a processor to carry out the steps of: a) Enrolling a user at an enrolment location by effecting a capture of a specific biometric from that user and associating that biometric with an identity element specific to that user, b) Applying a blinding function to the associated identity element so as to provide a blinded identity element, the blinding function taking the identity element as a data input and providing the blinded identity element as a data output, the blinded identity element revealing no information about the data input, c) generating a transaction identifier at the enrolment location; d) associating the transaction identifier with each of the biometric and blinded identity elements to form two combinations, e) Separately forwarding each of the two combinations to a storage location which is remote from the enrolment location, matching transaction identifiers from each of the two combinations, and combining the blinded identity element and the biometric-as an index pair, f) Storing the index pair as a stored pair at the storage location, and g) Retrieving the biometric from the stored pair by subsequently providing the same identity element, applying the same blinding function to that element so as to recreate the blinded identity element and using the recreated blinded identity element to retrieve the biometric stored with that blinded identity element, wherein the step of forwarding the combination having the blinded identity element to the storage location is via an index governor, the index governor, on receiving a blinded identity element being configured to apply a second blind function to the blinded identity element so as to generate a doubly blinded identity element which is coupled to the transaction identifier for forwarding to the storage location for association with the biometric and storage as a stored pair.