VISA Method
The VISA method is used by many card schemes and is not VISA-specific. The VISA method generates a PIN verification value (PVV). Similar to the offset value, it can be stored on the card's track data, or in a database at the card issuer. This is called the reference PVV.
The VISA method takes the rightmost eleven digits of the PAN excluding the checksum value, a PIN validation key index (PVKI, chosen from one to six) and the required PIN value to make a 64 bit number, the PVKI selects a validation key (PVK, of 128 bits) to encrypt this number. From this encrypted value, the PVV is found.
To validate the PIN, the issuing bank calculates a PVV value from the entered PIN and PAN and compares this value to the reference PVV. If the reference PVV and the calculated PVV match, the correct PIN was entered.
Unlike the IBM method, the VISA method doesn't derive a PIN. The PVV value is used to confirm the PIN entered at the terminal, was also used to generate the reference PVV. The PIN used to generate a PVV can be randomly generated or user selected or even derived using the IBM method.
Read more about this topic: Personal Identification Number, PIN Validation
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