What is Waterfall Model in Software Engineering

Waterfall Model is the primitive model in software engineering that evolved with time, put together all the phases in natural sequence.

Phases of Waterfall Model:

The phases of the waterfall model are as follows:

• Requirement Phase: It consists of extensive user participation and ends with an approved set of requirements documented called SRS.
• Design Phase: It works as a bridge between user wants and code that will be created to satisfy the requirement.
• Construction Phase: According to design and requirement coding is implemented. This phase consists of a large team.
• Testing Phase: After the construction testing phase is started. It involves the lowest component testing, then the testing of a group of components & then the whole system is tested and finally, acceptance testing is done to validate that the system fulfills user requirements or not.
• Deployment Phase: After the testing on this phase the user training, installation of the system are done.
• Operation & Maintenance Phase: This Phase helps to make the system more updated and also helps to reduce the defects if generated in the system.

Advantages of Model :

• The model has well-defined phases with well-defined output.
• It recognizes the sequence of software engineering activities in a software product.
• It is simple and easy to execute.
• This model is intuitive and logical.

Disadvantages of Waterfall Model:

• The Cycle time of this model is very long.
• In this model, there is no user feedback.
• The approach is very simple.
• The model assumes that requirements as clearly specified at a beginning of the project the model have no mechanism to handle changes to the phases once implemented.

Types of projects in which model is used:

• Short duration project are taken to implement by this model.
• Projects which require automation of adjusting manual sytem are implemented by this model.
• The projects which have well understood problem are implemented using this model.