Passthrough processing

Passthrough processing refers to the programmatic functions coded in, and managed by the service requester in order to fulfill a business transaction in the CICS® Service Flow Runtime.

Passthrough processing does not require developers to model an Adapter service to integrate with CICS target applications, and therefore is sometimes referred to as the non-tooled access pattern. It is supported for CICS Link3270 bridge processing only.

In passthrough processing, the request and response model is based on a one-screen-at-a-time conversation between the service requester and the target CICS application. The service requester sends a request message to the runtime environment, in which the application data portion of the message contains a BMS Application Data Structure (ADS) to satisfy:

CICS Service Flow Runtime recognizes the request as being a request for passthrough processing and handles it appropriately. In a scenario that uses passthrough processing, the service requester would be designed to handle the passthrough response. The passthrough response could contain multiple Link3270 outbound vectors however.

Using passthrough processing, the service requester is responsible for interpreting any or all BMS Application Data Structures (ADS), textual information sent as the result of a BMS SEND TEXT, CONVERSE or SEND command and any 3270 data streams sent as the result of a SEND or CONVERSE command and based on its interpretation takes appropriate action in the language of the service requester, JAVA for example, to satisfy the command issued by the target CICS application transaction.

The following characteristics apply to the processing of a passthrough request:

See the CICS External Interfaces Guide Version 2 Release 2 or higher for further information regarding the Link3270 bridge mechanism and associated processing.