1. CIF301 Project Quality Unit 6

2. Project Quality Introduction
“Quality” is generally agreed to be a good thing
Often the use of procedures that will help ensure a systems quality will be lacking
Quality systems must be defined
Metrics should be used to check quality systems

3. The importance of software quality
Increasing criticality of software
The intangibility of software
Accumulating errors during software development

4. Defining software quality
Should be three specification for software quality
a functional specification describing what the system does
a quality specification concerned with how the system operates
a resources specification concerned with how much will be spent on the system

5. ISO 9126 Published in 1991 Provides a definition for software quality
Is seen as the base on which more detailed standards can be built

6. ISO 9126 ISO 9126 defines six software quality characteristics
Functionality
which covers the functions that a software product provides to satisfy a user needs
Reliability
which relates to the capability of the software to maintain its level of performance

7. ISO 9126 Usability Efficiency Maintainability Portability
which relates to the effort needed to use the software
Efficiency
which relates to the physical resources used when the software is executed
Maintainability
which relates to the effort needed to make changes to the software
Portability
which relates to the ability of the software to be transferred to a different environment

8. Software quality measures
Reliability
Could measure
availability
mean time between failures
failure at time of operation
number of faults dealt with

9. Software quality measures
Maintainability
Closely related flexibility
Extendibility
Ease with which new features can be added to the software

10. Product versus process quality management
What is the difference?
Why is this important?
Often one or the other is looked at
Both should always be considered

11. BS EN ISO 9001 This is the standard for quality management systems
Current standard BS EN ISO 9001:2000
This is a family of standards.
2000 series superseded 1994 series
Standard grew out of DEF STAN and BS5750
There are other related quality standards

12. BS EN ISO 9001 BS EN ISO 9000 is a group of standards:
9000, fundamentals and vocabulary , Quality Management Systems requirements
9004, guidelines for performance improvement
9001 is the standard that applicants are assessed against.
It is a general standard that can be applied to any business or organisation

13. TickIT
The BS EN ISO 9000 series of standards refers to quality management systems in general
In the UK, the Department of Trade and Industry (DTI) have formulated the TickIT standards.
The TickIT standards give an interpretation of the BS EN ISO 9001 standard as it specifically applies to software development.

14. TickIT The main requirements of Tick IT are:
A detailed development plan is required before development is embarked upon.
Change control procedures should be used at all stages of development
Design reviews must take place
The suitability of the design methodology must be reviewed

15. TickIT main requirements of Tick IT (cont.)
Progress must be reviewed on a systematic basis
It must be possible to trace back the features of software design to specifications and requirements
Designs must be properly documented

16. TickIT main requirements of Tick IT (cont.)
Suitable test plans, specifications and records must be produced
A code of practice must be in place that governs the way the software is developed

17. TickIT The code of practice must include the following:
The design must be broken down into levels, each with identifiable inputs and outputs.
Software must be organised into modules.
A module must normally perform a single function or a set of related functions.
A plain language description must exist for each module.

18. TickIT
A TickIT auditor will certify that a particular organisation conforms to the standard
The process is referred to as certification
The TickIT scheme is now administered by a division of the British Standards Institute on behalf of the DTI

19. Capability Maturity Model
Developed in US by The Software Engineering Institute, Carnegie Mellon University.
The Capability Maturity Model attempts to place an organisation producing software at one of five levels.

20. Capability Maturity Model
Level 1: Initial
Level 2: Repeatable
Level 3: Defined
Level 4: Managed
Level 5: Optimizing

21. Capability Maturity Model
Level 1: Initial
The procedures followed tend to be haphazard.
Some projects will be successful, but this tends to be because of the skills of particular individuals including project managers.
There is no level 0 and so any organization would be at this level by default.

22. Capability Maturity Model
Level 2: Repeatable
Organizations at this level will have basic project management procedures in place.
The way an individual task is carried out will depend largely on the person doing it
Level 3: Defined
The organization has defined the way in which each task in the software development cycle is to be done.

23. Capability Maturity Model
Level 4: Managed
The products and processes involved in software development are subject to measurement and control.
Level 5: Optimizing
Improvement in procedures are designed and implemented using the data gathered from the measurement process

24. Ways to help enhance software quality
Increasing visibility
checking each others code
proposed by Weinberg in 1971in what he termed “egoless programming”
Procedural Structure
Checking intermediate stages

25. Conclusion IT Project Quality Quality definitions ISO 9126
BS EN ISO 9001
TickIT
The capability maturity model
Enhancing software quality