Flow oriented modeling
- 1. Flow Oriented Modeling Data flow diagram Control Flow Specification Process Specification
- 2. Definition: âIt 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 â
- 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.