OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
Its not the model - its what you do
SPIN-UK, 2 February 1999
2 February 1999
Slide 1
OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
Contents
• Characteristics of s/w process models
• Using models
• Change - approaches and strategies for SPI
• Tools for change
• Summary
2 February 1999
Slide 2
OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
Characteristics of s/w process models...
• Examples of models:
– SPICE
– CMM
– Bootstrap
– Trillium
– ISO 9000-3
2 February 1999
Slide 3
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…Characteristics of s/w process models...
• Models describe/prescribe what development practices are
advisable
• They do not describe how
2 February 1999
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…Characteristics of s/w process models
• Models tend to be:
– generic
– abstract (specifications rather than particulars)
– static, or steady state*
– conservative
– well considered (easy to criticize, difficult to improve)
* Abdel Hamid, Madnick ‘Software Project Dynamics’ model is a notable exception
2 February 1999
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2 February 1999
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Using the models...
• Models are used for:
– comparison
– emulation
– sources of information and ideas
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…Using the models...
Business
Objective
?
A Model
meets
Development
Process
2 February 1999
comparison
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…Using the models...
• Used in business context
– what are business requirements for s/w development?
– how do these relate to model requirements?
• Need to know how to compare (assess, evaluate, audit)
• Need to know how to emulate (make changes)
• ‘Judgement’ is critical
– indicates deficiencies
2 February 1999
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…Using the models
• Judgement is required:
– there is no equivalent to production engineering or production
management for s/w
– need to identify ‘appropriate technology’
• distinguish state of practice from state of art
• keep it simple
– need disinterested view of industry practices and cultures
2 February 1999
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2 February 1999
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Change - approaches to SPI...
• Top down
– directed by model
– directed by business need
• Bottom up
– fix current development problems
(these are not exclusive)
2 February 1999
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...Change - approaches to SPI...
For visibility
-metrics
-assessment
-QA
Frameworks
-PDCA
-TCM
-resource models
-PI templates
PI
- Process Definition
- work ‘upstream’
- piloting/rollout
- models
- ‘flat pack’ infrastructure
Top Down - directed by model
Assess
(e.g CBA IPI)
Planning
(e.g. DevPIP)
Framework
for action
(e.g. TCM)
2 February 1999
Tools
and
tactics
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...Change - approaches to SPI...
Top Down - directed by business objectives
Business need
(e.g reduce
costs)
Performance
target
(e.g. HP’s 10X)
Framework
for action
(e.g. TCM)
2 February 1999
For visibility
-metrics
-assessment
-QA
Frameworks
-PDCA
-TCM
-resource models
-PI templates
PI
- Process Definition
- work ‘upstream’
- piloting/rollout
- models
- ‘flat pack’ infrastructure
Tools
and
tactics
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...Change - approaches to SPI...
10X
•
“We need similar gains in the quality of our software products to achieve the same excellent
reputation for quality that our hardware products have earned. For this reason I an extending the
commitment made for hardware to software….
•
“HP is to achieve a tenfold improvement in two key software quality measures in the next five years.
The first measure is aimed at out design process; the second at our ability to solve problems once
customers have our products in place. We will measure these improvements by...
•
Post Release Defect Density - The total number of defects (KPRs) reported from any source, during
the first twelve months after first shipment, divided by the size (KNCSS) of the product. This
measure helps us to understand the effectiveness of our design and testing process and is in a format
widely used in industry.
•
“Open and Serious KPRs - The number of service requests classified as KPRs (Known Problem
Reports) which have a severity of critical or serious which are not yet closed or signed off at the end
of the month. This measure helps us to focus on the support process involved in providing permanent
solutions to severe customer problems.”
•
John Young HP’s CEO, 24 April 1986
2 February 1999
Slide 15
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Software Engineering Services & Consultancy
...Change - approaches to SPI...
Bottom Up - e.g. PIRL
Tools
and
tactics
trends and issues
Development
‘quick fixes’
2 February 1999
PIR’s
Focus for PI
(e.g. SEPG)
For visibility
-metrics
-assessment
-QA
Frameworks
-PDCA
-TCM
-resource models
-PI templates
PI
Process Definition
work ‘upstream’
piloting/rollout
models
‘flat pack’ infrastructure
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Software Engineering Services & Consultancy
...Change - approaches to SPI...
Top Down - directed by model
• Strengths
– available ‘off the shelf’
– others have done it
• Weaknesses
– may not address real issues
– expensive
– takes time
– high risk
2 February 1999
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...Change - approaches to SPI...
Top Down - directed by business objectives
• Strengths
– meets business needs
– generates commitment
• Weaknesses
– novel
2 February 1999
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...Change - approaches to SPI...
Bottom Up
• Strengths
– addresses real developer needs
– quick
– cheap
– effective
– low risk
• Weaknesses
– does not explicitly address business needs.
2 February 1999
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2 February 1999
Slide 20
OXFORD SOFTWARE ENGINEERING
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Tools...
• There are numerous tools and tactics for SPI
• They can be classified (loosely) into three types
– Visibility
– Frameworks for change
– Analysis and production
2 February 1999
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Software Engineering Services & Consultancy
…Tools...
Visibility
• Provide visibility and understanding of development processes
• Examples:
– Quality Assurance
– Measurement
– Assessment
2 February 1999
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OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
…Tools...
Frameworks for change
• Provide a secure, repeatable infrastructure for SPI activities
• Improve the probability of rapid completion of tasks
• Examples:
– PDCA
– TCM
– PI templates
– Grady - ‘spiral’
2 February 1999
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OXFORD SOFTWARE ENGINEERING
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…Tools
Analysis and production tools
• Develop artefacts
• Build understanding and consensus
• Examples:
– process definition
– PIRs
– ‘7 tools’
– ‘upstream’ analysis
– piloting and roll-out
– ‘flat pack’ infrastructure, etc...
2 February 1999
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OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
2 February 1999
Slide 25
OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
Summary
• Models are useful as static generic specifications
• Models can be used for comparison and emulation
• They do not address business needs or show how to make
changes
• Strategies tactics and tools for change are being developed
• Select elements to build effective SPI strategy equipped with
useful tools
2 February 1999
Slide 26
OXFORD SOFTWARE ENGINEERING
Software Engineering Services & Consultancy
OXFORD
S O FTWAR E E N G I N E E R I N G
LIMITED
9 Spinners Court, 53 West End,
Witney,
Oxfordshire
OX8 6 NS
tel. +44 (0) 1993 700878
email shelley@osel.netkonect.co.uk
www.osel.co.uk
2 February 1999
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