Strong Customer Authentication (SCA) is a European regulatory framework that describes three types of information that should be reviewed as part of an online payment transaction, so as to increase security and reduce fraud. To accept ecommerce payments once PSD2’s obligations go into effect, merchants will need to build authentication technologies into their checkout flows that measure at least two of the following three elements: 1. “Something you know”, the KNOWLEDGE Element (e.g., password or PIN) 2. “Something you have”, the POSSESSION Element (e.g., phone or hardware token)3. “Something you are” the INHERENCE Element (e.g., fingerprint or face recognition) https://www.signifyd.com/psd2-strong-customer-authentication/