The Server Application Classes 
General descriptions about the server application classes are available under the following topics:
The CRfcServerApp Class: Encapsulation of the Server Process Loop Using the CRfcServerApp and Derived Classes The CRfcTransApp Class and Transactional RFC Getting System Information from the Calling SystemComplete details are provided in the class library reference topics shown here:
The CRfcServerApp Class The CRfcTransApp Class