1.
ALPHA BREATHING

2.
EVOCATION

3.
Spiral Model
EVOLUTIONARY PROCESS MODELS

4.
 Proposed by Boehm
 Couples Iterative nature of prototyping + classic life cycle
waterfall model
 Potential for rapid development of increasingly more complete
version of software
 Software is developed in a series of evolutionary releases.
The Spiral Model

5.
A Typical Spiral Model

6.
 Divided into set of framework activities defined by the software
engineering team
 Each Framework activities represents 1 segment of a spiral
path
 As evolutionary process begins the software performs activities
implied by circuit in clockwise direction
 Begins at the center
Framework Activities

7.
 Function of each circuit:
 1st circuit – development of a product specification
 2nd circuit – prototype is developed(trial product)
 3rd and rest – sophisticated versions of software is developed
 For each pass:
 Planning : Adjustment of project plan is done
 Cost & schedule: Adjusted based on feedback of customer after delivery
 Project manager: Adjusts number of iteration to complete software
The Process

8.
 Anchor point milestones – a combination of work products and
conditions that are attained along the path of the spiral are noted
for each evolutionary pass.
 Circuit Representation:
 First circuit – concept development project
 Second circuit – new product development project
 Further circuits – product enhancement projects
Contd..

9.
 Realistic approach of development in large scale
 Developer and customer satisfaction
 Enables developer to apply prototype in any stage
 Stepwise approach
 Direct consideration of technical risk at all step.
Advantages

10.
 Demands considerable risk assessment expertise
 Model has not been used as widely as the linear sequential or
prototype paradigm
Disadvantages

11.
Mind Map

12.
Summary
 Evolutionary Process Models
 Spiral model
 Stages
 Communication
 Planning
 Modeling
 Construction
 Deployment
 Anchor point milestones
 Concept development project
 Product enhancement project
 Application: To build custom software and mobile apps which
requires enhanced versions. E.g.: windows, android, etc...

13.
1. A few years ago, Sun Microsystems, decided to develop and market StarOffice,
a set of desktop tools that would be comparable to Microsoft’s office suite of
tools but would be targeted for UNIX rather than Windows. At that time no other
major UNIX vendor had developed or was planning to develop such a product.
What process model would you use?
Stimulating Questions