BSCS CMS (Customer Management Server) Customization Overview. This course provides information about how to develop or customize CMS API using Java along with ORM (Toplink). BSCS is very well know telecom Billing System. One of the componenet of BSCS billing system is CMS which is also called Customer Management Server. The CMS server is based on CORBA Framework . This course provides details about plugin development of CMS API using Eclipse.