Architecture Antipatterns

Intro

• Arch. antipatterns are common problems and mistakes in the creation, implementation and management of the architecture.

Vendor Lock-in

• Symptoms:
  • Commercial component upgrades drive the application software maintenance cycle.
  • Commercial component does not subscribe to any open systems standard.
• Causes:
  • No technical approach to isolating application software from direct dependency on the product version.
• Fix:
  • Introduce an isolation layer
  • Hardware abstraction layer
  • Adoption of open systems standard and carefully choose components that meet this standard.

Jumble

• Vertical design elements are those dependent on specific software application and individual implementation.
• Horizontal elements are those that are common among applications.
• Symptoms:
  • Both the horizontal and vertical design elements get mixed up.
  • This makes design less stable and less reusable. Wide change impact.
• Causes:
  • No special effort involved, programmers just focused on getting job done.
• Fix:
  • Identify the horizontal elements and delegate them to a separate architectural layer.
  • Vertical elements as extensions for specialized functionality and performance.
  • Incorporate metadata into the architecture.

Architecture by implication

• Symptoms:
  • Lack of architecture specifications for a system under development. Usually, the architects responsible for the project have experience with previous system construction, and therefore assume that documentation is unnecessary.
  • Hidden risks caused by scale, domain knowledge, technology, and complexity, all of which emerge as the project progresses.
  • Ignorance of new technologies.
  • Absence of technical backup and contingency plans.
• Causes:
  • Overconfidence of managers, architects, and/or developers.
  • No risk management.
  • Reliance on previous experience.
• Fix:
  • Adopt SEI architecture based process steps.