Flow oriented modeling

flow oriented modeling

1. Flow Oriented Modeling Data flow diagram Control Flow Specification Process Specification

2. Definition: “It is based on structural analysis technique. Structured analysis is a software engineering technique that uses graphical diagrams to develop and portray system specifications that are easily understood by users “

3. Guidelines: Depict the system as a single bubble in level 0. Carefully note Primary input and output. Always starts with level 0, level 1 and then level 2. In level 1 we divide our input into different processes and assign work to each process. Label all elements with meaning names. Maintain Info conformity between levels. Refine one bubble at a time.

4. Data Flow Diagram Example :level 0

5. Level 1

6. Level 2

7. Control Flow Specification: A short term for control specification is CSPEC. The CFD contains the same processes as the DFD, but shows control flow, rather than data flow. It represents the behaviour of the system. The state diagram in CSPEC is a sequential specification of the behaviour. The state diagram includes states, transitions, events and activities. State diagram shows the transition from one state to another state if a particular event has occurred.

8. State diagram for Safe Home security function

9. Process Specification: A short term for process specification is PSPEC. The process specification is used to describe all flow model processes. The content of process specification consists narrative text, Program Design Language(PDL) of the process algorithm, mathematical equations, tables or UML activity diagram. A process specification (PSPEC) can be used to specify the processing details implied by a bubble within a DFD.

10. Process Specification(Written Description):