Waterfall model is the classical model of software development where each phase of software development is completed in a linear fashion. Once one phase is over then next phase starts and in the end the software development is marked completed. Waterfall model works for smaller projects and has one single cycle of development. Following are the phases:
Requirement Analysis -> Designing -> Implementation -> Testing -> Deployment -> Maintenance
RAD Model or Rapid Development Model is also known as incremental model of software development. It allows changes in any stage which was very costly in case of waterfall model. It has multiple cycles and each cycle delivers a version of a software and after each cycle, new features are added and software is enhanced.
Following are some of the important differences between Waterfall Model and RAD Model.
|Sr. No.||Key||Waterfall Model||RAD Model|
|1||Name||Waterfall model is also named as Classical or Traditional Model.||RAD Model, Rapid Development Model is also named as Iterative Model.|
|2||Risk||Waterfall model is a high risk model for software development.||RAD model is a low risk model for software development.|
|3||Team Size||Waterfall model requires large team to start software development.||In RAD model, team size can be increased or decreased as the development progresses.|
|4||Changes||Any changes to be done should in the earlier phases of development otherwise, it is very costly to fix.||Changes can be done in any phase.|
|5||Product Delivery||Water fall model delivers product in the end of the software development cycle.||RAD model gives earlier deliveries and seeks feedback to update the software as needed.|
|6||Waiting Time||A running or ready software is available at the end stage of development.||A running or ready software is avaiable as soon as first iteration is complete.|