DCASS stands for the Derivatives Clearing And Settlement System and serves as a single clearing， settlement and risk management system for the HKFE Clearing Corporation Limited (HKCC) and The SEHK Options Clearing House Limited (SEOCH). DCASS was launched in April 2004 and was upgraded to the Genium INET Platform in October 2013.
DCASS is a fully electronic and automated system capable of supporting various types of derivatives products such as equities， foreign exchange， interest rate and commodities. It shares the same technology platform and infrastructure as the derivatives trading system， Hong Kong Futures Automated Trading System (HKATS) and provides a seamless operational environment for derivatives trading and clearing. DCASS processes clearing transactions in real-time and provides extensive access to clearing data to support the risk management functions.
CCMS stands for Common Collateral Management System which is used to manage the collateral holdings and obligations of Clearing Participants (CPs) of HKCC and SEOCH. As an integrated part of CCASS system， CCMS is serving both Securities and Listed Derivatives markets by accepting a wide range of collateral types and providing cross-market collateral management capability.
CPs can access DCASS through DCASS Servers and DCASS Terminal. DCASS Server is a machine that is installed with server application to connect to DCASS through OMnet Application Programme Interface (OAPI) via Network Gateway/Central Gateway and the dedicated network (SDNet) for information exchange. DCASS Terminal is a workstation that is installed with front-end application， which is connected to the DCASS Server for CP to perform manual input of post-trade activities.
HKEX also provides an alternative for CPs to connect their back-office systems to DCASS through their self-developed OAPI applications on a host-to-host basis. CPs with high clearing volume can consider accessing DCASS through this direct OAPI approach to facilitate their straight through processing for improved operational efficiency.
CPs can access CCMS through browser-based terminal， CCASS or CCMS Terminal. Any PC running supported versions of Microsoft Windows， Internet Explorer and Java Runtime Environment is able to access all CCMS functions.