Post on 22-Dec-2015
Software Quality Matters
Ronan FitzpatrickSchool of Computing
Dublin Institute of Technology
Outline
Definitions, models and standards The Software Quality Star Perspectives of software quality Strategic drivers of software
quality
Objective
To provide an introduction to the issues that impact software quality as seen through the eyes of a software quality assurance manager.
Definitions
Fitness for purpose Compliance with specification
A measure of excellence measure Low quality, high quality excellence the presence of product
attributes
Definitions of software quality - 1
German Industry Standard DIN 55350 Part 11
Quality comprises all characteristics and significant features of a product or an activity which relate to the satisfying of given requirements.
ANSI Standard (ANSI/ASQC A3/1978) Quality is the totality of features and characteristics of a
product or a service that bears on its ability to satisfy the given needs.
ISO/IEC 9126 (1991) The totality of features and characteristics of a software
product that bear on its ability to satisfy stated or implied needs.
Definitions of software quality - 2
IEEE Standard (IEEE Std 729-1983) The totality of features and characteristics of a
software product that bear on its ability to satisfy given needs: for example, conform to specifications.
The degree to which software possesses a desired combination of attributes.
The degree to which a customer or user perceives that software meets his or her composite expectations.
The composite characteristics of software that determine the degree to which the software in use will meet the expectations of the customer.
Shortcommings of these definitions
Focus only on product attributes or characteristics and to a lesser degree on use
Do not consider the potential to achieve quality through best practice
Management, development, staffing, operations
Models
The House of Quality
Standards
ISO/IEC 12207(1995)
Software Quality Star
Copyright 2000 © Ronan Fitzpatrick
QualitySTAR
Contract
Project
Process
Producer Procurer
Product
User
ISProfessional
Perspectives of software quality
The Product perspective Quality attributes
The Contract perspective Quality assurance review and planning
The Supplier (producer) perspective Producer, project and process
The Acquirer (procurer) perspective Procurer, IS professional and user
The product perspective
EXTERNAL QUALITY FACTORS
INTERNAL QUALITY
FACTORS
STRATEGIC QUALITY
FACTORS
CORE QUALITY
FACTORS
Suitability Installability Functionality Adaptability Ease-of-use Learnability
Interoperability Reliability Safety Security Correctness Efficiency
Maintainability Testability Flexibility Reusability Portability
DOMAIN-SPECIFIC QUALITY
FACTORS
Visibility Intelligibility Credibility Engagibility
Differentiation
The contract perspectiveQuality assurance planning per ISO/IEC 12207 (1995)
Quality standards, methodologies, procedures, and tools for performing the quality assurance activities (or their references in organisation’s official documentation)
Procedures for contract review and coordination thereof
Procedures for identification, collection, filing, maintenance and disposition of quality records
Resources, schedule, and responsibilities for conducting the quality assurance activities
Selected activities and tasks from supporting processes, such as Verification (6.4), Validation (6.5), Joint Review (6.6), Audit (6.7), and problem Resolution (6.8).
The supplier perspective
Producer
Project
Process
The supplier perspectiveProducer
Enlightened philosophy and leadership
Employing first-rate staff Who engage in first-rate processes Using first-rate tools and
techniques To create quality software
products
The supplier perspective Project
ISO 12207 (1995) onus on supplier to develop and document project management plans implement and execute the project management plans
Project management planning issues are 1. Organisation and environment 2. Acquirer involvement 3. Acquirer requirements and quality characteristic 4. WBS, resources and contractors 5. Quality assurance/validation and verification 6. Risk management 7. Licensing, usage and ownership 8. Tracking, documenting and reporting 9. Personnel training
Planning quality detail
Acquirer requirements and quality characteristics
define their quality requirements and quantify the quality
characteristics of the software product
Quality assurance/validation and verification
item testing, integration testing, system testing and acceptance testing
Capability Maturity Model
People P-CMM
Other issues Schedule Budget
The supplier perspective Process
Life cycle processes per ISO/IEC 12207
Capability Maturity Model SPICE ISO 9001 certification
Life cycle processes
6.3 Quality Assurance
1. Process implementation – requires that a quality assurance process tailored to the project should be established
2. Product assurance – requires that plans and procedures be established to ensure that the software product meets the requirements specification
3. Process assurance – requires that the life cycle processes used by the supplier organisation comply with the contract
4. Assurance of quality systems – requires that the ISO 9001 quality management activities are assured.
Capability Maturity Model
SW-CMM
The acquirer perspective
Procurer
IS professional
User
The acquirer perspective Procurer
Can be supported by the IS professionals Will be acceptable to the user community
Also, but not addressed by ISO/IEC 12207 Provides some form of competitive advantage Value for money Complies with any legal obligations Matched current business processes
The acquirer perspective IS professional
Advise to management regarding the specification
Technical excellence, user empowerment, corporate alignment, investment efficiency, supplier organisation
profile.
Perspective is influenced by role viz, development professional or support
professional
The acquirer perspective User - usability
Product-centred view of usability: that the usability of a product is the attributes of the product
which contribute towards the quality-of-use.
Context-of-use view of usability: that usability depends on the nature of the user, product,
task and environment.
The quality-of-use view of usability: that usability is the outcome of interaction and can be measured by
the effectiveness, efficiency and satisfaction with which specified users achieve specified goals in particular environments.
Strategic drivers of software quality
Perspectives of the Software Quality Star are derived from the contracting arrangement of ISO/IEC 12207.
Does not consider all the strategic business issues of either the acquirer or the supplier.
Solution is a new Software Quality Strategic Driver Model.
Corporatealignment
Technicalexcellence
Useracceptance
Investmentefficient
Competitivesupport
Statutoryconformance
Corporateaccreditation
Qualitymanagement
Software Quality – Strategic Driver Model
Copyright © 2000 Ronan Fitzpatrick
Domainspeciality
Competitiveexcellence
Developmentexcellence
QualitySTAR
Contract
Project
Process
Producer Procurer
Product
User
ISProfessional
Strategic Driver Model
Can it be developed further This research developed SQ-SDM
Is there potential to adapt the model for Network Management NM-SDM e-Commerce eCom-SDM Customer Relationship Management CRM-SDM and similar
Conclusion
Definitions, models and standards Definitions are not fully accurate
The Software Quality Star Based on ISO/IEC 12207 (1995)
Perspectives of software quality Contract, supplier, product and acquirer
Strategic drivers of software quality
Procurer perspective Producer perspective