This means that every time a customer wants to make a digital transaction, they must authenticate with at least two of these factors to confirm the transaction: Knowledge factor : something that only the customer knows. It can be a PIN, a password, etc. Possession factor : something phone number list only the client owns. It can be a card or a mobile phone, etc. Inherence factor: something phone number list is inherent to the client, that is, a biometric identification element. It can be fingerprint, voice recognition, etc. Thus, the most used factors until now to make any purchase on the Internet were the phone number list number and the security code (CVV). With the entry into force of the European regulations, these are no longer considered sufficiently safe, and for this the 3 factors mentioned above are established.

In addition, this digital transaction will be processed through a "Secure Purchase" protocol (3D Secure)adapted. 3DSecure is an authentication system developed by the main bank card brands (“Verified by Visa” or “SecureCode” in the case of Mastercard, among others) that authenticate and verify the cardholder in the purchase process. The best phone number list method is the sending of an SMS by the bank to the customer's mobile associated with the bank card. This mechanism has been used until now, but it was an optional procedure. With the entry into phone number list of PSD2, it becomes mandatory. SCA _It is a requirement at European level, which will be required for all those digital transactions in which the service provider, such as the card provider or the bank, is within the European Economic Area (EEA).