Software Architecture

Introduction to Software Architecture

• Software architecture encompasses the set of significant decisions about the organization of a software system :
  • Selection of structural elements and their interfaces by which a system is composed.
  • Behaviour as specified in collaborations among those elements.
  • Composition of these structural and behavioural elements into larger subsystem.
  • Architectural style that guides this organization.

• Definition:
  • The structure or structures of the system which comprise of software elements, the externally visible properties of those elements and the relationships among them.

Why Architecture

Communication

• There are different stakeholders (client, user, project manager, developer, maintainer) who want different qualities of the system being built.
• E.g. client is concerned about cost, user about usability, project manager about dividing work, developer about implementation and maintainer about making changes.
• An architecture provides a framework and structure for airing these concerns.