For Issuing Bank
Access Control Server (ACS): It manages the authentication process for cardholders. When a cardholder makes a purchase request, the 3-D Secure Requestor initiates the ACS authentication process through 3-D Secure Server and 3-D Secure SDK. In an App-based payment flow, ACS communicates directly with the cardholder through the 3-D Secure SDK to authenticate the identity of the cardholder.
ACS Cardholder Management System (CMS): This web based administration tool of ACS helps issuers to manage cardholder account maintenance, risk decision management, transaction reporting, configuration, user access control and audit trails.
For Acquiring Bank and Merchant (3DS Requestor)
3DS Server: It provides the functional interface between the 3DS Requestor system and Card Scheme Directory Server (DS). It provides API calls for 3DS Requestor website or 3DS Requestor mobile APP to initiate the 3DS authentication process.
3DS SDK: It provides API calls within the mobile application to collect device information. It also acts as a connector and message handler with ACS during the 3DS 2.0 flow.