message control vs with out message control

Message control and output type. In R/3, message control is a mechanism by which documents are output based on certain selection criteria, requirements, and sequences. Message control determines the type of document, its timing, number, and medium (print, fax, ALE, or EDI.). Outbound messages in SD (Sales and Distribution) and MM (Materials Management, Purchasing) are created and processed by message control records. The output records are stored in the NAST table.

Message control uses the condition technique. The conditions for creating an output message are stored in condition tables that have selection fields picked from a catalog of application fields/tables. To determine if an application document qualifies for output, search strategies are used through access sequences, output procedures, and requirements. Once a message qualifies for output, message control modules use the parameters set in the condition type or output type to determine the timing of transmission and the medium of the message. The output type also specifies the program or module to be invoked to create the output.

Message/output determinations are concepts applicable not only to EDI and ALE, but also to other output mediums.