In this waterfall model, the phases do not overlap.
The waterfall methodology uses a sequential or linear approach to software development. Each phase must be completed before the next phase can begin and there is no overlapping in the phases.
1. Requirement Gathering and analysis 2. System Design 3. Implementation 4. Integration and Testing 5. Deployment of system 6. Maintenance
1. It does not allow much reflection or revision. 2. If the requirement changes then, it is hard to do again from the initial stage. 3. It doesn’t follow continuous development. 4. High amounts of risk and uncertainty.
5. Poor model for long and ongoing projects. 6. Not suitable for the projects where requirements are at a moderate to high risk of changing
Agile is a methodology that delivers software or value incrementally from the start of the project instead of all at once at the end. In this model, Analysis, Design, coding, and testing is continuous activities.