Transcript Document

OHT 3.1
• The need for comprehensive software quality
requirements
• Classification of requirements into software quality
factors
• Product operation factors
• Product revision factors
• Product transition factors
• Alternative models of software quality factors
• Who is interested in defining quality requirements?
• Software compliance with quality factors
Galin, SQA from theory to implementation
© Pearson Education Limited 2004
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The need for comprehensive SQ
Requirements
OHT 3.2
• “our new sales information system seems okay, the
invoices are correct, the inventory records are correct,
the discounts granted to our clients exactly follow our
very complicated discount policy, but our new sales
information system frequently fails, usually at least twice
a day, each time for twenty minutes or more…”
• “Just half a year ago, we launched our new product –
the radar detector. The firmware RD-8.1., embedded in
this product, seems to be the cause for its success. But
when we began planning the development of a
European version of the product, we found out that
though the products will be almost similar; our software
development department needs to develop new
firmware; almost all the design and programming will be
new”
Galin, SQA from theory to implementation
© Pearson Education Limited 2004
2
OHT 3.3
“But’s …”
• All the software project fulfilled the basic
requirements
• All the software project suffered from poor
performance in important areas
• The cause for the poor performance:
– Lack of predefined requirements to cover
these important aspects of the software’s
functionality  need for a comprehensive
definition of requirements
Galin, SQA from theory to implementation
© Pearson Education Limited 2004
3
OHT 3.4
Software quality factors
Product operation factors
Product revision factors
Product transition factors
Galin, SQA from theory to implementation
© Pearson Education Limited 2004
4
OHT 3.5
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Correctness
Reliability
Efficiency
Integrity
Usability
Galin, SQA from theory to implementation
© Pearson Education Limited 2004
5
OHT 3.6
• Maintainability
• Flexibility
• Testability
Galin, SQA from theory to implementation
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6
OHT 3.7
• Portability
• Reusability
• Interoperability
Galin, SQA from theory to implementation
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7
OHT 3.8
Galin, SQA from theory to implementation
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OHT 3.9
Alternative factor models
No.
Software quality
factor
McCall’s classic
model
Evans and
Marciniak model
Deutsch and
Willis model
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Correctness
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Reliability
Efficiency
Integrity
Usability
Maintainability
Flexibility
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Testability
Portability
Reusability
Interoperability
Verifiability
Expandability
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Safety
Manageability
Survivability
Galin, SQA from theory to implementation
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© Pearson Education Limited 2004
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