The Software Quality Star:
A conceptual model for the software quality curriculum
Ronan Fitzpatrick
School of Computing,
Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland.
Email: ronan.fitzpatrick@comp.dit.ie
INTERACT 2003: Closing the Gaps.
Ninth IFIP TC International Conference on
Human-Computer Interaction
1 - 2 September, 2003
Zurich, Switzerland
Overview

Originating philosophy
• ISI/IEC 12207
Software Quality Star
 Perspectives of software quality

• Perspectives of Producer, Product and Procurer
Closing the Gaps
 Strategic Driver Model
 Questions

The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Software life cycle processes
Purpose

An international standard
ISO/IEC 12207:1995(E) that
– establishes a common framework for software life
cycle processes.
– uses well-defined terminology
– is suitable for all sectors in the software industry
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Software life cycle processes
Field of application

Intended for use in a two-party situations
– parties from different organisations
– parties from same organisation
– single party/self imposed tasks


Not intended for off-the-shelf software products
unless incorporated into a deliverable product.
Written for the
– acquirer, supplier, developers, operators, maintainers
– managers, QA managers and end-users
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Software life cycle processes
Structure of the international standard ISO/IEC 12207 (1995)
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Software life cycle processes
Five Primary life cycle processes
ENGINEERING VIEW
5.3 Development process
Process
implementation
System
requirements
analysis
System
architectural
design
Software
Software
requirements architectural
analysis
design
Software
detailed
design
Software
installation
Software
acceptance
support
System
integration
System
qualification
testing
Process
implementation
Software
integration
Software
qualification
testing
Modification
implementation
Software
coding and testing
The Software Quality Star
5.5 Maintenance process
Migration
Ronan Fitzpatrick
Problem &
modification
analysis
Maintenance
review/
acceptance
Software
retirement
Closing The Gaps, September 2003, Zurich
Software life cycle processes
Five primary life cycle processes
(plus Supporting and Organisational)
5.1 Acquisition process
End
5.2 Supply process
5.3 Development process
5.4 Operation process
5.5 Maintenance process
6. Supporting life cycle process
(documentation, configuration management, Quality assurance and problem resolution)
Start
7. Organisational life cycle process
The Software Quality
Star
(management,
Ronan Fitzpatrick
Closing
The Gaps, September 2003, Zurich
infrastructure,
improvement
and training)
Quality focus
Provides a common framework and
vocabulary.
 Written with QA manager in mind.
 Addresses need quality planning.
 Specifies unit, integration, system and
acceptance testing.
 Identifies the ongoing need for process
improvement.

The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
The Software Quality Star
Contract
Producer
Project
– Supplier,
– developers,
– managers,
– QA managers.
Procurer
Quality
STAR
User
– Acquirer
Process
The Software Quality Star
IS
Professional
Product
Ronan Fitzpatrick
– operators,
– maintainers,
– managers,
– end-users.
Closing The Gaps, September 2003, Zurich
The Producer’s perspective

Producer
– Competitive excellence - best in their field
– Corporate accreditation - e.g., CMM, ISO
– Domain speciality - knowledge and expertise of the procurer
organisation’s business processes

Project
– Development excellence, i.e., best project management
standards and practice (e.g., P-CMM)

Process
– Quality management, i.e., building in quality requirements as
specified in the contract.
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
The Product perspective
Quality factors






Suitability
Installability
Functionality
Adaptability
Ease-of-use
Learnability
EXTERNAL
INTERNAL
QUALITY FACTORS
QUALITY FACTORS






Interoperability
Reliability
Safety
Security
Correctness
Efficiency
The Software Quality Star
Ronan Fitzpatrick





Maintainability
Testability
Flexibility
Reusability
Portability
Closing The Gaps, September 2003, Zurich
The Procurer’s perspective

Procurer
–
–
–
–

Competitive support - support for competitive position
Investment efficient - value for money
Statutory conformance - complies with legal obligations
Corporate alignment - product is in keeping with
organisation’s business strategy
User
– User acceptance - acceptable and usable by user community

IS professional
– Technical excellence - serviceable and maintainable
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Closing the Gap

Software life cycle and Software quality
– More than testing, permeates all perspectives
– At postgraduate level
» Group of mixed primary degree - BSc, BEng, BBS,
MBCS, BA,
– At undergraduate level
» BSc and BBS
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Closing the Gap
Identifies the various stakeholders and their
perspectives
 Allows stakeholders and students for any
discipline to understand the perspectives of
stakeholders and students from other
disciplines
 Provides a common model for all.

The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Closing the Gap

Software Engineering – HCI
– SE considerations
» Development excellence, i.e., best project management standards and
practice (e.g., P-CMM):
» Quality management, i.e., building in quality requirements as specified in
the contract.
– HCI considerations (acceptable an usable)
» Usability – All 12 external quality factors per slide 11
» Usability evaluation - Usability methods and techniques


» Usability quotient - numerically quantify/metrics
» Views of usability – product-centred view, context-of-use view and quality-ofuse view which includes effectiveness, efficiency and satisfaction.
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Closing the Gap
Originally developed with a Quality focus
 Focus of this presentation is HCI


The Software Quality Star can have its
focus tailored to suit whatever discipline is
being thought, typically, Security.
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Software Quality – Strategic Driver Model
Competitive
support
Competitive
excellence
Investment
efficient
Corporate
accreditation
Contract
Producer
Domain
speciality
Project
Procurer
Quality
STAR
User
Development
excellence
Statutory
conformance
Corporate
alignment
User
acceptance
Process
Quality
management
The Software Quality Star
IS
Professional
Product
Ronan Fitzpatrick
Technical
excellence
Copyright © 2000
Ronan2003,
Fitzpatrick
Closing The Gaps, September
Zurich
Conclusion

Originating philosophy
• ISI/IEC 12207
Software Quality Star
 Perspectives of software quality

• Perspectives of Producer, Product and Procurer
Closing the Gaps
 Strategic Driver Model

The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Closing the Gap
QUESTIONS
The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
The Product perspective
Quality factors






Suitability
Installability
Functionality
Adaptability
Ease-of-use
Learnability
EXTERNAL
INTERNAL
QUALITY FACTORS
QUALITY FACTORS






Interoperability
Reliability
Safety
Security
Correctness
Efficiency





Maintainability
Testability
Flexibility
Reusability
Portability

The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich
Usability methods
as named by ISO/TR 16982
Usability Methods
Observation of users
Performance-related
measurements
Critical incidents
Questionnaires
Interviews
Thinking aloud
Collaborative design and
evaluation
Creativity methods
Document-based methods
Model-based approaches
Expert evaluation
Automated evaluation
Additional Methods and Techniques
Electronic surveys
Log files
Video capture
Scan converter
Focus groups
Parallel design
Brainstorming

The Software Quality Star
Ronan Fitzpatrick
Closing The Gaps, September 2003, Zurich