3D Secure or 3DS is the protocol that identifies each transaction with the card issuing bank. Once the identification process is complete, the two banking institutions have confirmed the safety of the transaction and proceed to complete the transfer.
When you perform an online transaction with a Magenta Pay card, you will receive a push notification on the mobile device you use to access the Magenta Pay app. Once you pass the relevant security check, you can either accept or reject the transaction. If you accept it, the transaction is executed normally and your card is charged with the amount you are required to pay to the merchant.
If you reject it, the transaction will not go through.