quartz/content/notes/000 This Semester/002 Courses/Software and Engineering/Chapter 2/Spiral model.md

Spiral model

1. Introduction

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Definition :: Spiral model is a combination of systematic aspect of Waterfall Model and iterative nature of Prototype Model

Spiral Model = systematic approach of **Waterfall** + iterative nature of **prototyping**

2. When to use spiral model?

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• When software is big
• Need to solve as much risk as possible
• Requirments are complex
• Significant changes are aspected

3. Four fold procedure

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1. Evoluation
2. Defining
3. Planning/Design
4. Engineering !

4. Phases of Spira Model

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• Requirement Analysis
• Prototyping
• Coding and testing
• Customer's Evoluation !Pasted image 20220205052425.png

5. Advatage

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• The possibility of risk in the product signaficly reduce
• Very flexible
• Good for lard project
• Additional functionality can be added
• Software produces earlu

6. Disadvantage

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• Waste for small project
• Highly depends on removing risk
• Need expertise for removing risk
• The success is depends on risk removing phase