Software engineering 17 architectural design

Software engineering 17 architectural design

• 1.
  Software Engineering: 17 ArchitecturalDesign Prof Neeraj Bhargava Vaibhav Khanna Department of Computer Science School of Engineering and Systems Sciences Maharshi Dayanand Saraswati University Ajmer
• 2.
  Architectural design • Architecturaldesign is concerned with: – understanding how a software system should be organized and, – designing the overall structure of that system. • Architectural design is the critical link between design and requirements engineering, as it identifies the main structural components in a system and the relationships between them. • The output of the architectural design process is an architectural model that describes how the system is organized as a set of communicating components
• 3.
  Architectural abstraction • Architecturein 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 are distributed over different computers, which may be owned and managed by different companies.
• 4.
  Advantages of explicitarchitecture • Stakeholder communication – Architecture may be used as a focus of discussion by system stakeholders. • System analysis – Means that analysis of whether the system can meet its non-functional requirements is possible. • Large-scale reuse – The architecture may be reusable across a range of systems – Product-line architectures may be developed.
• 5.
  Architectural representations • Simple,informal block diagrams showing entities and relationships are the most frequently used method for documenting software architectures. • But these have been criticized because they lack semantics, do not show the types of relationships between entities nor the visible properties of entities in the architecture. • Depends on the use of architectural models. The requirements for model semantics depends on how the models are used.
• 6.
  Example architecture ofa packing robot control system
• 7.
  Box and linediagrams • Very abstract - they do not show the nature of component relationships nor the externally visible properties of the sub-systems. • However, useful for communication with stakeholders and for project planning
• 8.
  Use of architecturalmodels • As a way of facilitating discussion about the system design – A high-level architectural view of a system is useful for communication with system stakeholders and project planning because it is not cluttered with detail. Stakeholders can relate to it and understand an abstract view of the system. They can then discuss the system as a whole without being confused by detail. • As a way of documenting an architecture that has been designed – The aim here is to produce a complete system model that shows the different components in a system, their interfaces and their connections.
• 9.
  Architectural design decisions •Architectural design is a creative process so the process differs depending on the type of system being developed. • However, a number of common decisions span all design processes and these decisions affect the non-functional characteristics of the system.
• 10.
  Architectural design decisions
• 11.
  Architecture reuse • Systemsin the same domain often have similar architectures that reflect domain concepts. • Application product lines are built around a core architecture with variants that satisfy particular customer requirements. • The architecture of a system may be designed around one of more architectural patterns or ‘styles’. – These capture the essence of an architecture and can be instantiated in different ways.
• 12.
  Architecture and systemcharacteristics • Performance – Localize critical operations and minimize communications. Use large rather than fine-grain components to reduce the components’ communication. • Security – Use a layered architecture with critical assets in the inner layers. • Safety – Localize safety-critical features in a small number of sub-systems. • Availability – Include redundant components and mechanisms for fault tolerance. • Maintainability – Use fine-grain, replaceable components.
• 13.
  Assignments • Explain theconcept of Architectural Design and the advantages of good Architectural Design • What are the major design decisions that we have to take in Architectural Design • Thank You