First, you can define the information flows between application system types, module types, or IT functions. For this purpose, an information flow object is created between the corresponding application system types or module types. In order to specify the information flow between system types in more detail, an eERM diagram, a relations diagram, or a table diagram is linked with the information flow object. Thus, the information flow objects may be located either at the requirements definition level, design specification level, or implementation level.

An example is shown in the following figure.

Besides the information flows, input and output data of every application system type, module type, and IT function type can be represented as data objects of the requirements definition or design specification. The direction of the arrows indicates whether it is an incoming (input) or outgoing (output) data flow.

An example is shown in the following figure.