Exercise 1
Task 1
❖ Architectural Design
➢ Architectural design is concerned with understanding how a software system should be
organized and designing the overall structure of that system.
➢ It is the critical link between design and requirements engineering, as it identifies the main
structural components in a system and the relationships between them.
➢ Architecture in the small is concerned with the architecture of individual programs. At this
level, we are concerned with the way that an individual program is decomposed into
components.
➢ Architecture in the large is concerned with the architecture of complex enterprise systems
that include other systems, programs, and program components. These enterprise systems
may be distributed over different computers, which may be owned and managed by
different companies.
➢ Designing and documenting software architecture has three advantages:
▪ Stakeholder communication
▪ System analysis
▪ Large-scale reuse
➢ System architectures are often modeled informally using simple block diagrams, Block
diagrams present a high-level picture of the system structure, which people from different
disciplines, who are involved in the system development process, can readily understand.
➢ Bass et al. (Bass, Clements, and Kazman 2012) dislike informal block diagrams for describing
an architecture. They claim that these informal diagrams are poor architectural
representations, as they show neither the type of the relationships among system
components nor the components’ externally visible properties.
➢ There are two ways in which an architectural model of a program is used:
▪ As a way of encouraging discussions about the system design
▪ As a way of documenting an architecture that has been designed
❖ Architectural design decisions
➢ Architectural design is a creative process in which you design a system organization that will
satisfy the functional and non-functional requirements of a system.
➢ Several common decisions span all design processes, and these decisions affect the non-
functional characteristics of the system.
➢ Because of the close relationship between non-functional system characteristics and
software architecture, the choice of architectural style and structure should depend on the
non-functional requirements of the system:
▪ Performance
▪ Security
▪ Safety
▪ Availability
▪ Maintainability
❖ Architectural views
➢ It is impossible to represent all relevant information about a system’s architecture in a single
diagram, as a graphical model can only show one view or perspective of the system.
➢ Each architectural model only shows one view or perspective of the system.
