The mechanism used to send requests initiated from a CICS program to a remote Oracle Tuxedo domain is invisible to the user and significantly abstracted from the CICS programmer. Your company’s CICS program issues an EXEC CICS LINK command to the Oracle TMA gateway. In the data passed with the EXEC CICS LINK command, the programmer supplies the name of the service and the data to be used as input to that service. When the EXEC CICS LINK command returns, the reply to the request is placed in that same data area. If there was a problem satisfying the service request, meaningful return codes are sent back.

As the following figure illustrates the configuration of the Oracle TMA client gateway. A client program (your CICS program) issues an EXEC CICS LINK command to the Pre-requester. The Pre-requester verifies that the service name is valid and identifies the Requester to which it should it should pass the request. The Pre-requester starts a different Requester for each configured remote endpoint. The Requester then sends the request to the remote Oracle Tuxedo domain and waits for a response. Once the response is returned, the Requester notifies the Pre-requester and hands the response to the Pre-requester, which then returns the response to the client program.