Processing examples

Figure 1 shows how the CICS® business logic interface processes a request from an MVS™ application that uses the EXCI.

Figure 1. Processing a request from the EXCI
This figure shows how the CICS business logic interface processes a request from an MVS application that uses the EXCI
  1. The MVS application constructs a COMMAREA that contains parameters for the CICS business logic interface.
  2. The MVS application uses the EXCI to call the CICS business logic interface.
  3. The CICS business logic interface calls the requested service, and returns any output in the COMMAREA.

Figure 2 shows how the CICS business logic interface processes a request from a CICS client that uses the ECI.

Figure 2. Processing a request from the ECI
This figure shows how the CICS business logic interface processes a request from a CICS client that uses the ECI.
  1. The client, running in a workstation environment, constructs a COMMAREA that contains parameters for the CICS business logic interface.
  2. The client uses the ECI to call the CICS business logic interface.
  3. The CICS business logic interface calls the requested service, and returns any output in the COMMAREA.

The ECI operates with either the SNA protocol or with TCP62, which allows a SNA connection over TCP/IP (see the CICS Family: Client/Server Programming for further information).