ITEC 3010 Lecture Notes - Data Flow Diagram, System Context Diagram, System Model

• School: York University
• Department: Information Technology
• Course: ITEC 3010
• Professor: all

Document Summary

Lecture 6 data flow diagrams oct 26. The square is an external agent: a person or organization, outside the boundary of a system that provides data inputs or accepts data outputs. The rectangle with rounded edges is a process: a symbol that represents an algorithm or procedure by which data inputs are transformed into data outputs. The lines are data flows: represents movement of data. The flat three-sided rectangle are data stores (a file or part of a database: a place where data is held. 6-5 shows a context diagram for a university course registration system that interacts with 3 agents: academic dept. , student, and faculty member. External agents are outside the software scope (which is represented by the single process). Data stores are not shown in the context diagram since they are considered to be in the software scope (i. e. the single process)