Software Quality
Author: Claire Lohr
Presenter: Ehsan
Ghaneie
What is quality?
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The degree to which a system, component,
or process meets specified requirements
The degree to which a system, component,
or process meets customer or user needs or
expectations
Other Definitions:
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Conformance to user requirements
Achieving excellent levels of fitness for use
Market-driven quality
Customer-driven quality
TQM principals
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Everyone has a customer
There is quantitative feedback from all
customers
Corrective actions occur based on the
measures
Every process has an owner
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Software Quality Activities:
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Quality Assurance (QA)
Quality Control
Software Engineering
Culture and Ethics
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Establish code of ethics for all participants
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Impossible for SQA organization to create desired
level of quality by itself
Every one has to be committed
Usually part of a larger quality improvement
program
Value and Cost of Quality
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Cost of poor quality software:
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Cost of improving quality:
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Internal and external failures
Prevention and appraisal
Cost of improving quality is more than offset
by savings resulting from higher quality
Models for Quality in Software
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CMMI-SW
ISO 9001:2000
ISO 90003
TickIt
Six Sigma
Plan, Do, Check, Act (PCDA)
CMMI
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Ratings from 1 to 5:
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1 – Initial
2 – Repeatable
3 – Defined
4 – Managed
5 – Optimizing
ISO 9001 Requirements for Quality
Management System
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General Requirements
Documentation Requirements
Management Responsibility
Resource Management
Product Realization
Measurement, analysis, and improvement
Planning for SQA
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IEEE Std. 730: Standard for Software Quality
Assurance
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Choose process improvement model
Plan the organization
Show documentation in the life cycle context
Add review, audit, test, problem reporting, and corrective
action tasks
Develop the measurement goals and processes
Peer review of the SQAP
Maintenance of the SQAP
Minimum Documentation IEEE Std. 730
Requires
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Software requirements description (SRD)
Software design description (SDD)
Verification and validation plans
Verification and validation results report
User documentation
Software configuration management plan
(SCMP)
Other (defined by the user of the standard)
Minimum Software Reviews IEEE Std.
730 Requires
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Software specifications review (SPR)
Architecture design review (ADR)
Detailed design review (DDR)
Verification and validation plan review
Functional audit
Physical audit
In-process audits
Managerial reviews
Software CM plan review (SCMPR)
Post-implementation review
Other reviews and audits as defined
Key Processes to Support SQA
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SQA process
Verification process
Validation process
Review process
SQA Process Includes:
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Setting standards
Checking compliance with standards
Revising standards
Coaching participants
Collecting, evaluating, and reporting metrics
Disseminating best practice examples
Proposing potential improvements
Measurement for SQA
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Desirable attributes
Undesirable attributes
Each quality criteria can be evaluated with a
metric
Metric Attributes
According to IEEE Std. 1061
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Name
Costs
Benefit
Impact
Target Value
Quality Factor
Tools
Application
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Data item
Computation
Interpretation
Considerations
Training required
Example
Validation history
References
Recommended Life Cycle for Quality
Metrics
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Establish software quality requirements
Identify software quality metrics
Implement the software quality metrics
Analyze the software quality metrics results
Validate the software quality metrics
Conclusion
References:
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http://www.swebok.org/
http://www.tickit.org/
http://www.sei.cmu.edu/cmmi/
http://en.wikipedia.org/wiki/CMMI/
Thank you!