A Remote Function Call (RFC) is the call or remote execution of a Remote Function Module in an external system. In the SAP system, these functions are provided by the RFC interface system. The RFC interface system enables function calls between two SAP systems. There are 3 different versions of RFC communication:
The RFC interface system is made up of the following interfaces:
If either the calling program or the called partner is not an SAP program, it must be programmed in such a way that it can play the role of the other partner in RFC communication.
To implement RFC partner programs in non-SAP systems, read: Components of the SAP Communication Technology.
RFC-supported and GUI-supported interfaces can be used by external programs to call and execute function modules in SAP systems. Likewise, ABAP programs can also use these interfaces to use functions supplied by external programs.
Functions are remote-enabled by setting the "Remote-enabled module"-flag in the Attributes tab of the ABAP Workbench: Function Builder (transaction SE37).
SAPRFC is an open source program for *NIX and Windows systems that allows PHP to make calls to an RFC-enabled SAP R/3 system.
RFC documentation by SAP https://help.sap.com/saphelp_nw70/helpdata/en/6f/1bd5b6a85b11d6b28500508b5d5211/frameset.htm ↩