3D Secure? What is it?

3D Secure is a protocol designed to be an additional security layer for online credit and debit card transactions. The name refers to the “three domains” which interact using the protocol:

  • Merchant/Acquirer domain (the financial institution and merchant to which the money is being paid).
  • Issuer domain (the financial institution which issued the card being used).
  • Interoperability domain (the infrastructure provided by the card scheme, e.g. Mastercard, VISA etc).