Functional Modeling and Information Flow

The Information is transformed as it flows by a computer based system. The system accepts input in a range of forms and applies software, hardware and human parts to transform input into output and produces output in a variety of forms. The Input may be a control signal transmitted by a transducer a series of numbers typed by a human operator a packet of information transmitted on a network link or a voluminous data file retrieved form a CD-ROM. The transforms may comprise advance of an expert system. The Output may light a single LED or produce a 200-page report. By the effect we can build a flow model for any computer based system, regardless of size and complexity.

The Structured analysis starts as an information flow modeling methods. A computer-based system is represented as information transform. Overall function of the system is represented as a single information transform noted as a bubble in the figure which is given below. One or more inputs shown as labeled arrows originate from external entities presented as a box. The input drives the transform to produce output information also represented as labeled arrows which is passed to the external entity. It should be noted in which the model might be applied to the entire system or to the software part only. The key is to represent the information fed into and produced through the transform.