Structured Process Analysis
Systems Analysts use various modeling techniques to demonstrate their understanding of how business processes and systems operate. In this unit, we will explore some traditional techniques to model processes, and how they help analysts visualize how systems work.
While these techniques are technology agnostic, and may not be widely used, we study these techniques to help develop an understanding of how processes can be decomposed and evaluated. In the next unit, we will study industry standard techniques for object-oriented process modeling, using the Unified Modeling Language, which has been standardized for use in many information technology organizations.
“Processes can be modeled in many different ways, but this unit will focus on data flow diagrams, or DFDs. DFDs are very useful for representing the overall data flows into, through, and out of an information system. DFDs rely on four symbols to represent the four conceptual components of a process model: data flows, data stores, processes, and sources/sinks. DFDs are hierarchical in nature, and each level of a DFD can be decomposed into smaller, simpler units on a lower-level diagram. You begin process modeling by constructing a context diagram, which shows the entire system as a single process. The next step is to generate a level-0 diagram, which shows the most important high-level processes in the system. You then decompose each process in the level-0 diagram, as warranted, until it makes no sense to go any further. When decomposing DFDs from one level to the next, it is important that the diagrams be balanced; that is, inputs and outputs on one level must be conserved on the next level.”
Valacich, J. S., & George, J. F. (2017). Modern systems analysis and design (8th ed.). Boston: Pearson.
Activities
- Read: Chapter 7 in Modern Systems Analysis and Design
- Complete practical assignment 6.1 (PA-6.1)
- Complete written assignment 6.1 (WA 6.1)
Objectives
- understand the logical modeling of processes by studying examples of data flow diagrams,
- draw data flow diagrams following specific rules and guidelines that lead to accurate and well-structured process models,
- decompose data flow diagrams into lower-level diagrams,
- balance higher-level and lower-level data flow diagrams,
- use data flow diagrams as a tool to support the analysis of information systems,
- discuss process modeling for electronic commerce applications, and
- use decision tables to represent the logic of choice in conditional statements.
Topics
- Process Modeling
- Data Flow Diagramming Mechanics
- Data Flow Diagramming
- Modeling Logic With Decision Tables
- E-Commerce Application Process Modeling