Waterfall model

Posted By on April 24, 2016

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Software Development Process Models
  • The Waterfall Model was first Process Model to be introduced.
  • It is also referred to as a linear-sequential life cycle model.
  • It is very simple to understand and use.
  • In a waterfall model, each phase must be completed fully before the next phase can begin.
  • This type of model is basically used for the for the project which is small and there are no uncertain requirements.
  • At the end of each phase, a review takes place to determine if the project is on the right path and whether or not to continue or discard the project.
  • In this model the testing starts only after the development is complete.
  • In waterfall model phases do not overlap.

Diagram of Waterfall-model:

Waterfall model

Advantages of waterfall model:

  • This model is simple and easy to understand and use.
  • It is easy to manage due to the rigidity of the model – each phase has specific deliverables and a review process.
  • In this model phases are processed and completed one at a time. Phases do not overlap.
  • Waterfall model works well for smaller projects where requirements are very well understood.

 Disadvantages of waterfall model:

  • Once an application is in the testing stage, it is very difficult to go back and change something that was not well-thought out in the concept stage.
  • No working software is produced until late during the life cycle.
  • High amounts of risk and uncertainty.
  • Not a good model for complex and object-oriented projects.
  • Poor model for long and ongoing projects.
  • Not suitable for the projects where requirements are at a moderate to high risk of changing.

When to use the waterfall model:

  • This model is used only when the requirements are very well known, clear and fixed.
  • Product definition is stable.
  • Technology is understood.
  • There are no ambiguous requirements
  • Ample resources with required expertise are available freely
  • The project is short.


Software Development Process Models

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Posted by Akash Kurup

Founder and C.E.O, World4Engineers Educationist and Entrepreneur by passion. Orator and blogger by hobby

Website: http://world4engineers.com