ITM 410 Chapter Notes - Chapter 4: Data Flow Diagram, Supply Chain Management Software, System Context Diagram

• School: Ryerson University
• Department: Information Technology Management
• Course: ITM 410
• Professor: Selcuk Savas

Document Summary

We use documentation to understand and improve a systems. Two types of systems documentation considered are: data flow diagrams and systems flowchart. Dfd depicts a systems compnents; the data flows among the components and the courses, destinations, and storage of data. Is a graphical representation of a system showing the systems internal and external entitird and the flows of data into and out of these entities. Internal entity is an entity (person, place or thing) withithn the system that transforms data. Does not tell us what what activities are being accomplished. Is a graphical representation of a system showing the systems processes (bubbles), data stores, and the flows of data into and out of the processes and data stores. Are used to document information systems b/c we can represent the logical nature of a system. Adv of logical dfd over physical is that we can concentrate on the functions that a system performs.