Method of reconstruction of a measurement of the reference database of a confidential from a measurement of this database noisy

摘要

The invention relates to a method of enrolling a reference data item w in a device intended to retrieve a reference measurement of a confidential data item on the basis of a noisy measurement of said data item, characterized in that it comprises at least the following steps: a1) selecting a secret key Sk, a2) performing a reference measurement of said confidential data item, a3) applying an Extend function suitable for increasing the size of the measured data item by using the secret key and the extend function in order to generate an extended data item we, a4) applying a secure sketch function in its enrolment phase so as to find the data item s. The method comprises an additional step of reconstructing the extended reference data item we. The method comprises an additional step in which the inverse function of the function Extendsk is used, by taking as input the extended data item we as well as the key Sk so as to retrieve the data item w.