Easy to realize

1. Waterfall Model
Presented By
Md. Zabirul Islam (1507110)
Tanim Ahmed (1507113)
Md. Motaleb Hossen Manik (1507114)
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2. CONTENTS
 Introduction
 What is Waterfall Model
 Real Life Example
 Stages
 Scenario
 When to use Waterfall Model
 Advantages
 Disadvantages
 Conclusion
 QA
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3. INTRODUCTION
 Introduced by Winston W. Royce in 1970.
 The waterfall model is the classic lifecycle model.
The waterfall Model illustrates the software development process in a
linear sequential flow.
This means that any phase in the development process begins only if
the previous phase is complete.
 Provides structure to inexperienced staff.
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4. REAL LIFE EXAMPLE
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HSC
ADMISSION
TEST
SSC

5. STAGES OR PHASES
It has 6 phases and they are:
i. RequirementAnalysis
ii. System Design
iii. Implementation and Unit Testing
iv. Integration and System Testing
v. Deployment
vi. Maintenance
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6. SCENARIO
 Although previous is a virtual
scenario but in real life scenario we
see some difference
 In real life we don’t justify the every
previous stage while working in the
present stage
 For this reason we find defects or
bug at the final stage
 Then we start blaming each another.
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7. WHEN TO USE THE WATERFALL MODEL?
 Requirements Are Very WellKnown and Fixed.
 Product Definition Is Stable.
 Technology Is Understood.
 The Client Has High Confidence In The Organization.
 The Project Is Short.
 New Version Of An Existing Product.
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8. ADVANTAGES
18
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 Easy to understand, easy to implementation ,easy to use
 It helps to find error earlier
 Works well when quality is more important than cost or schedule
 Milestones are clear
 Testing is done at every stage.
 Process and results are well documented.
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9. DISADVANTAGES
 Poor model for long and ongoing projects
 Difficult to go back for changing
 No software produces until finalization
 Not good for OOP and complex projects
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10. CONTINUE…
 Difficult to estimate time, cost
 Constant testing needed
 Not suitable for frequently changeable projects
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11. CONCLUSION
 May the wrong choice will not be discovered until final stage
 But can be used for small ,trivial projects
 Where requirements are known before starting
Example: Mobile game development (Pure Waterfall Model)
 Again Canonical for space, medical and life-critical systems i.e. flight control
software, airbag systems, etc.
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12. REFERENCES
1) https://www.oxagile.com/company/blog/the-waterfall-model/
2) https://xbsoftware.com/blog/software-development-life-cycle-waterfall-model/
3) http://istqbexamcertification.com/what-is-waterfall-model-advantages-disadvantages-
and-when-to-use-it/
4) https://study.com/academy/lesson/waterfall-model-advantages-disadvantages.html
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