Chapter 5 – System modeling. The aim of this chapter is to introduce some types of system model that may be developed as part of the requirements engineering and system design processes. When you have read the chapter, you will: understand how graphical models can be used to represent software systems; understand why different types of model are required and the fundamental system modeling perspectives of context, interaction, structure, and behavior | Chapter 5 – System Modeling Lecture 1 1 Chapter 5 System modeling Topics covered Context models Interaction models Structural models Behavioral models Model-driven engineering 2 Chapter 5 System modeling System modeling System modeling is the process of developing abstract models of a system, with each model presenting a different view or perspective of that system. System modeling has now come to mean representing a system using some kind of graphical notation, which is now almost always based on notations in the Unified Modeling Language (UML). System modelling helps the analyst to understand the functionality of the system and models are used to communicate with customers. 3 Chapter 5 System modeling Existing and planned system models Models of the existing system are used during requirements engineering. They help clarify what the existing system does and can be used as a basis for discussing its strengths and weaknesses. These then lead to requirements for the new system. Models | Chapter 5 – System Modeling Lecture 1 1 Chapter 5 System modeling Topics covered Context models Interaction models Structural models Behavioral models Model-driven engineering 2 Chapter 5 System modeling System modeling System modeling is the process of developing abstract models of a system, with each model presenting a different view or perspective of that system. System modeling has now come to mean representing a system using some kind of graphical notation, which is now almost always based on notations in the Unified Modeling Language (UML). System modelling helps the analyst to understand the functionality of the system and models are used to communicate with customers. 3 Chapter 5 System modeling Existing and planned system models Models of the existing system are used during requirements engineering. They help clarify what the existing system does and can be used as a basis for discussing its strengths and weaknesses. These then lead to requirements for the new system. Models of the new system are used during requirements engineering to help explain the proposed requirements to other system stakeholders. Engineers use these models to discuss design proposals and to document the system for implementation. In a model-driven engineering process, it is possible to generate a complete or partial system implementation from the system model. 4 Chapter 5 System modeling System perspectives An external perspective, where you model the context or environment of the system. An interaction perspective, where you model the interactions between a system and its environment, or between the components of a system. A structural perspective, where you model the organization of a system or the structure of the data that is processed by the system. A behavioral perspective, where you model the dynamic behavior of the system and how it responds to events. 5 Chapter 5 System modeling UML diagram types Activity diagrams, which show the activities involved in a process or in data
