RFC and programming information for RFC client/server programs can be summarized as follows:
An RFC connection is always initiated by an RFC client program.
An RFC connection is always built up in two steps:
Connection from an RFC client to the SAP gateway
Connection from the SAP gateway to an RFC server
There are different ways of starting or connecting to an RFC server program:
An RFC server program can be registered at an SAP gateway. The program waits for RFC requests from SAP systems.
Note
The registered server is the standard method for connecting an RFC server.
You can start an RFC server program via the SAP gateway or the currently running application server.
Note
Starting the RFC server via an application server is not recommended if you are expecting frequent calls on this server.
For program start-up options while establishing an RFC connection, see