CICS business logic interface: Processing examples

Examples of how the CICS® business logic interface processes a request from a z/OS® application that uses either the EXCI or the ECI.

Example: Processing a request from the EXCI

Figure 1 shows how the CICS business logic interface processes a request from a z/OS 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 a z/OS application that uses the EXCI
  1. The z/OS application constructs a COMMAREA that contains parameters for the CICS business logic interface.
  2. The z/OS 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.

Example: Processing a request from the ECI

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 an SNA connection over TCP/IP (see the CICS Family: Client/Server Programming for further information).