SE 380 Software Architecture

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SE 380Software Architecture

• Part 4.
• Moving From One to Many

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Where are we?

• We have
• Envisioned an architecture
• Part 1 ABC, Definitions, Patterns
• Created an architecture
• Part 2 Quality Attributes, Scenarios, Tactics
• Evaluated an architecture
• Part 3 ATAM, CBAM
• Now, lets generalize a little and look at
  applying an architecture to a family of products.

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The Holy-Grail Reusable Software

• Re-use is common in other disciplines
• Examples
• Electronics
• Mechanical systems
• Building and construction
• The ability to reuse software components would
  have a huge impact, but it has been largely
  unfulfilled.
• Granularity is a problem.
• Architecture becomes a key to reuse.

4
Software Product Lines

• Definition a set of software-intensive systems
  sharing a common, managed set of features that
  satisfy the specific needs of a particular market
  segment or mission and that are developed from a
  common set of core assets in a prescribed way.
  Clements
• Examples

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Examples Allen-Bradley Drives
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Examples
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Architecture and Product Lines

• Identifying variation points
• How do the products vary?
• Supporting variation points
• How can we generalize the variation?
• How can we support specific variants?
• Evaluating the architecture
• Focus on variation points and economy of
  variation against quality attributes.
• ? Performance

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CelsiusTech Case Study

• Organization before and after adopting a product
  line strategy
• Before Each subsystem had a project manager
  with direct authority over teams.
• After Program general manager, architecture
  team, custom project, integration, and product
  line teams.

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Keys to Architecture

• Top-down vs. Bottom-up
• Proactive vs. Reactive
• Requires a Vision
• Requires a Champion
• Architectural Strategies
• Modifiability
• Visionary abstraction
• Semantic coherence