In SDLC, certain models are used for designing the software development process. These models help in the sequence of flow for development and will render a successful project. It gives management of the project and hence called as “Software Development Process Models”. These models will start from the feasibility study and continue till the completion of a project.
The different types of software models are:
1.Waterfall Model
2.RAD Model
3.Spiral Model
4.Incremental Model
5.Agile Model
6.Iterative Model
1.WATERFALL MODEL:
Waterfall model is the step-by-step procedure where the software development phases are completed one by one before the other phase is being started. It is the continuous process for software development model. It follows top-to-bottom approach. The activities are sequential in this approach and this approach is known as Linear-Sequential lifecycle model. The process will move to the next phase only if the previous phase is completed. Waterfall model can be used when the requirement is clear and the application is not complicated.
PHASES IN WATERFALL MODEL:
1.Requirement Analysis
2.System Design
3.Implementation
4.System Testing
5.System Deployment
6.System Maintenance
2.RAD MODEL:
RAD model is Rapid Application Development, it is based prototyping method for development. It takes less time to gather the requirements. RAD does not require specific planning. It uses an incremental and iterative approach. In this model, more priority is given to the development of the tasks rather than planning.
3.SPIRAL MODEL:
Spiral Model is the combination of iterative and waterfall model. It is the important model that is used for supporting Risk Handling. This model is used for large projects. It consists of spirals with loops that constantly used to build the projects. Each loop is called as the phase of the software process in the spiral.
PHASES IN SPIRAL MODEL:
1.Planning phase
2.Risk analysis phase
3.Engineering phase
4.Evaluation phase.
4.INCREMENTAL MODEL:
In this model, the requirements will be distributed into several modules known as standalone software modules. Each module will be processed through the requirements, design, testing and implementation phases. A series of increments are made to improve the functionality progressively for the client.
5.AGILE MODEL:
Agile methodology is used for continual planning, implementation and development of the project. It involves early delivery of the product. This method is of short time span and will last up to one to four weeks. The tasks are divided into timeboxes and specific features will be delivered after completion.
PHASES IN AGILE MODEL:
1.Requirements gathering
2.Design the requirements
3.Construction/ iteration
4.Testing/ Quality assurance
5.Deployment
6.Feedback
6.ITERATIVE MODEL:
In iterative model, it starts with the simple implementation process with all the software requirements and will iteratively improve the versions, till the project remain completed and deployed. When there is a change in the software, then the new version of the software can be created and iterated. Here, in this phase the earlier phases can also be accessed and the final output will be renewed accordingly.
PHASES OF ITERATIVE MODEL:
1.Requirements Phase
2.Design Phase
3.Implementation and Test
4.Review Phase
