(IEEE) A diagram that depicts data sources, data sinks, data storage, and processes performed on data as nodes, and logical flow of data as links between the nodes. Syn: data flowchart, data flow graph.
The diagrams in the logical architecture view of the National ITS Architecture that show the functions that are required for ITS and the information that moves between these functions. Only four different symbols are used on the diagrams. Circles represent the processes or functions that do the work. Arrows represent the data flows that show how data moves through the system. Parallel lines represent data stores that represent "data at rest" in the system. Finally, rectangles represent the terminators that define the architecture boundary. A hierarchy of these diagrams depict the ITS functionality and data flow requirements in successively greater detail until "primitive" processes are defined. The data flow diagrams are directly viewable as GIF images and also available as editable WMF graphics. Select "Logical Architecture" from the main menu, then select a data flow diagram from the provided list. View a sample data flow diagram available for downloading in wmf format.
An important technique for modeling high level detail in a process within a system. They highlight the functions of the system and how they use stored information and transfer information between each other.
A data flow diagram (DFD) is a graphical representation of the "flow" of data through an information system. A data flow diagram can also be used for the visualization of data processing (structured design). It is common practise for a designer to draw a context-level DFD first which shows the interaction between the system and outside entities.