METHOD FOR TOKENISATION OF THE BANK CARD NUMBER AND METHOD FOR DETOKENISATION OF THE BANK CARD NUMBER Russian patent published in 2021 - IPC G06F21/64 G06Q20/40 

FIELD: computing technology.

SUBSTANCE: computer-implemented method for tokenisation of the PAN (Primary Account Number) bank card number, wherein PAN is received and divided into the components thereof: bin (BIN) consisting of the first six characters, mask (MASK) consisting of the last four characters, and the middle part (mPAN); the offset value in the substitution table is determined wherein: the first offset value is calculated by the substitution table using cryptographic transformation of a concatenated string of the BIN and MASK values; the second offset value is calculated by the substitution table using mPAN cryptographic transformation; the sum offset value is calculated by adding the first and second offset values; the index in the substitution table is calculated by normalising the sum offset value by to the substitution table, wherein normalisation is performed according to the dimension of the table as the remainder from dividing the offset by the number of rows of the table, resulting in the sought index in the substitution table; using the obtained index, the tokenised part of the zPAN number is selected from the substitution table to replace mPAN; the tokenised DPAN card number is formed by replacing mPAN with zPAN, using BIN and MASK of the obtained PAN number.

EFFECT: increase in the efficiency of protection of bank card numbers.

7 cl, 3 dwg