In this chapter you will learn how to draw data flow diagrams, a popular process model that documents a system’s processes and their data flows. You will know process modeling as a systems analysis tool when you can: Define systems modeling and differentiate between logical and physical system models, define process modeling and explain its benefits, recognize and understand the basic concepts and constructs of a process model,. | Chapter 9 Process Modeling Objectives Define systems modeling and differentiate logical and physical models. Define process modeling and explain its benefits. Recognize and understand basic concepts and constructs of a process model. Read and interpret a data flow diagram. Explain when to construct process models and where to store them. Construct a context diagram to illustrate a system’s interfaces with its environment. Identify use cases, external and temporal business events. Perform event partitioning and organize events in a functional decomposition diagram. Draw event diagrams and merge them into a system diagram. Draw primitive data flow diagrams and describe the elementary data flows in terms of data structures and procedural logic. Document the distribution of processes to locations. Synchronize data and process models using a CRUD matrix. 9- 9- Models: Logical and Physical Logical model – a nontechnical pictorial representation that depicts what a system is or does. | Chapter 9 Process Modeling Objectives Define systems modeling and differentiate logical and physical models. Define process modeling and explain its benefits. Recognize and understand basic concepts and constructs of a process model. Read and interpret a data flow diagram. Explain when to construct process models and where to store them. Construct a context diagram to illustrate a system’s interfaces with its environment. Identify use cases, external and temporal business events. Perform event partitioning and organize events in a functional decomposition diagram. Draw event diagrams and merge them into a system diagram. Draw primitive data flow diagrams and describe the elementary data flows in terms of data structures and procedural logic. Document the distribution of processes to locations. Synchronize data and process models using a CRUD matrix. 9- 9- Models: Logical and Physical Logical model – a nontechnical pictorial representation that depicts what a system is or does. Synonyms or essential model, conceptual model, and business model. Physical model – a technical pictorial representation that depicts what a system is or does and how the system is implemented. Synonyms are implementation model and technical model. Model – a pictorial representation of reality. Just as a picture is worth a thousand words, most models are pictorial representations of reality. 9- Why Logical System Models Logical models remove biases that are the result of the way the system is currently implemented, or the way that any one person thinks the system might be implemented. Logical models reduce the risk of missing business requirements because we are too preoccupied with technical results. Logical models allow us to communicate with end-users in nontechnical or less technical languages. 9- Process Modeling and DFDs Process modeling – a technique used to organize and document a system’s processes. Flow of data through processes Logic Policies Procedures Data flow
