It was first introduced as a process model. The model is easy to use. This model requires that each phase be completed before moving on to the next. The phases do not overlap. This is the first SDLC method used in software development. It is easy to use and understand. It is easier to maintain since only one phase takes place at a time. Each phase is completed separately and does not overlap. The Waterfall Model is ideal for small projects with well-understood requirements. The results can be documented. Waterfall models have some drawbacks. For example, they cannot adapt to new requirements. The waterfall model is difficult to return to an earlier phase. Let’s say that during a particular stage, it is necessary to return to an earlier stage. This would be extremely difficult. The method is not suitable for ongoing and long-term projects.
The second model is the agile one. Agile SDLC model is an iterative process that uses incremental and iterative models. The focus of the model is on customer satisfaction and process adaptability. Agile methods break up the product in small incremental builds. These builds come in iterations. Iterations typically last between one and three weeks. Each iteration includes cross-functional team members working on different areas at the same time. Agile models are a more realistic way of developing software. It requires very little planning, and is easy-to-manage. It can deliver early partial solutions. It gives developers flexibility. Agile models have some disadvantages, such as the fact that they are not designed to handle complex dependencies. Sustainability, maintainability, and extensibility are at greater risk. The documentation is minimal, resulting in a high level of individual dependence. Lack of documentation may also make it hard to transfer the technology to a new member of a team. Rapid Application Development uses rapid prototyping instead of extensive planning. Functional modules are designed simultaneously and integrated to create a product. This allows for a faster delivery. Customer can give feedback and provide early visibility into the software. It can reduce development time since all prototypes will be created simultaneously. The RAD model increases reusability, and the initial review is quick. The customer can give feedback early on. It increases the reusability. The model is not without its disadvantages. It relies on the performance of a team as well as individual members to determine business needs. This model requires highly skilled designers and developers. The cost of automated code generation and modeling may be high.
