The document describes the waterfall model of software development. It introduces the waterfall model and explains that it is a linear sequential process where each phase must be completed before moving to the next. The phases include requirements analysis, system design, implementation, testing, deployment, and maintenance. While the waterfall model provides structure, it is not suitable for complex or changing projects since changes later in the process are difficult to implement. The model works best for small, well-defined projects where requirements are known upfront.

1. Waterfall Model
Presented By
Md. Zabirul Islam (1507110)
Tanim Ahmed (1507113)
Md. Motaleb Hossen Manik (1507114)
5/9/2018

2. CONTENTS
 Introduction
 What is Waterfall Model
 Real Life Example
 Stages
 Scenario
 When to use Waterfall Model
 Advantages
 Disadvantages
 Conclusion
 QA
5/9/2018 2

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.
5/9/2018 3

4. REAL LIFE EXAMPLE
5/9/2018 4
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
5/9/2018 5

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.
5/9/2018 6

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.
5/9/2018
7

8. ADVANTAGES
18
UniversityofEducationOkara
Campus
 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.
85/9/2018

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
5/9/2018 9

10. CONTINUE…
 Difficult to estimate time, cost
 Constant testing needed
 Not suitable for frequently changeable projects
5/9/2018 10

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.
5/9/2018 11

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
5/9/2018 12

13. 5/9/2018 13

14. 5/9/2018 14