3D Secure 2 (3DS2) introduces “frictionless authentication” and improves the purchase experience compared to 3D Secure 1. It is the main card authentication method used to meet Strong Customer Authentication (SCA) requirements in Europe and a key mechanism for businesses to request exemptions to SCA.

3D Secure (3DS) is an authentication method that provides an additional layer of authentication for credit card transactions, protecting against fraudulent actors. 3DS asks your customers to verify their identity with the card issuer during payment.

The key distinction between a 3DS 2.0 challenge authentication flow and a 3DS 1.0 traditional authentication flow is that with the former, the cardholder is required to verify their identity using either a one-time authentication code (provided by the issuer) or biometric data.

As previously mentioned, there are three domains of 3D Secure, the acquiring bank, the issuing bank, and the interoperability domain, which consists of the parties that connect the two to enable transactions. The Access Control Server (ACS) exists within the issuing bank's domain.