- The waterfall model is also called as Linear Sequential Model/Traditional Model.
- Waterfall Model is the step-by-step implementation of the SDLC model.
- In the waterfall model whenever 1st stage occurs then and then the procedure goes to the next stage.
- Generally, the waterfall model uses in small-scale companies and in product base company.
- This is used in small-scale industries where the time duration of the project is 3-4 months.
- Example: To build a car we create a concept of the car, design a car, build it and then test it.
- Same way, the waterfall model says that you build a software model sequentially one phase after the other. Since the flow is sequential, this model is very simple to understand and easy to implement.
Stages or Phases in Waterfall Model
- It is a requirement gathering from customers or Clients.
- Information gathering involves business requirement specification (BRS) which is prepared by Business Analyst (BA).
- A business Analyst (BA) involves in this process and here software requirement specification (SRS) document is made which is named Software/System Requirement Specification.
- Based on the requirements specified in Software requirement specification (SRS) a Design Document Specification (DDS) OR Technical Design Document (TDD) is proposed and documented.
- In the development phase, a Set of programs is written by the developer and creates software.
- In the testing phase, Testers test the software by using methods, techniques, and tools.
- Testing is the process of checking the completeness and correctness of the software.
- Once the product is tested and ready to be deployed it is released formally in the appropriate market (on a production server). Sometimes product deployment happens in stages as per the organization, business strategy.
- Maintenance means proving service after delivery (like bugs or improvement or enhancement) of the project.
- After delivery of any bug or enhancement occurs then all come under maintenance.
- Maintenance involves non-technical as well as technical support.
How did errors fix in the waterfall model?
In the waterfall model, when the tester found any bug then that bug does not send to the developer, instead of doing the tester log that bug and makes a report, and then those bugs are fixed in the next version of the product.
Advantages and disadvantages :
Advantages of waterfall model:
1. Simple and easy to understand.
2. Easy to Manage.
3. Phases do not overlap.
4. Best for small projects.
Disadvantages of waterfall model :
1. Difficult to go back and change something.
2. Late attention to the testing activity.
3. Hard to ensure quality because the testing team has not been involved in the project from the earlier phase.
4. Errors are more costly to correct.