cs2340: Design Validation and Design Reviews

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cs2340 Design Validation and Design Reviews

• Spring 2007

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Questions from MS and Google Interviews

• What is good design vs. bad design?
• What are tradeoffs involved with software
  features?
• Design an ATM for children.

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What makes one design better?

• Not functionality of software!!
• 50-80 of product costs in OM
• What things makes OM easier?

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Design Criteria

• F functionality
• U usability
• R reliability
• P performance
• S security/safety/sustainability

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Quality Factors

• Maintainability
• Testability
• Reliability/Availability
• Precision and Accuracy
• Security
• Performance
• Portability
• Extensibility
• Interoperability
• Usability

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Questions from MS Interview

• What is good design vs. bad design?
• What are tradeoffs involved with software
  features?
• Design an ATM for children.

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Why not just do them all?

• Trade-Off analysis

Maintainability
Security
Portability
performance
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Software Architecture Analysis Method (SAAM)

• Create scenarios of potential use and change of
  the system
• Create one or more representations of the
  architecture/design
• For applications categorize as direct or indirect
  scenario
• For indirect scenarios, evaluate impact on
  architecture
• Summarize impacts

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Design Reviews

• We normally use a set checklist
• Used to ensure understanding and quality
  standards met
• http//www-static.cc.gatech.edu/classes/AY2007/cs4
  911_fall/Design20Review20Checklist.doc
• http//www-static.cc.gatech.edu/classes/AY2007/cs4
  911_fall/ooreview.html

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Questions from MS Interview

• What is good design vs. bad design?
• What are tradeoffs involved with software
  features?
• Design an ATM for children.

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Friday Class

• Meet in your teams.
• Perform SAAM analysis of your architecture and a
  Design Review of your application
• Submit on Wednesday for 1 pt extra credit