Waterfall Model The waterfall is the first-ever, simplest, and one of the best SDLC methodology in the history of software development. The process of development in this model is linear and all the phases are completed one by one. As the name implies, like a waterfall, the progress of development flows downwards.
Waterfall model. The waterfall model is the earliest and the simplest of all the SDLC methodologies. The whole software development process is separated into phases, each phase beginning only when the previous one is completed.
1. Agile. The Agile model first emerged in 2001 and has since become the de facto industry standard. Some businesses value the Agile methodology so much that they apply it to other types of projects, including nontech initiatives.
Agile SDLC is an excellent software development method for businesses that constantly release software to meet customers' needs and client requirements. One of the major benefits of an Agile SDLC is that it promotes cross-functional team collaboration and feedback sharing.
Waterfall development method
Many consider the waterfall method to be the most traditional software development method. The waterfall method is a rigid linear model that consists of sequential phases (requirements, design, implementation, verification, maintenance) focusing on distinct goals.
Advantages of the Waterfall model. Waterfall relies on teams following a sequence of steps and never moving forward until the previous phase has been completed. This structure is suited to smaller projects with deliverables that are easy to define from the start.
Waterfall is a better method when a project must meet strict regulations as it requires deliverables for each phase before proceeding to the next one. Alternatively, Agile is better suited for teams that plan on moving fast, experimenting with direction and don't know how the final project will look before they start.
The agile model works great for projects that need flexibility and speed. Such projects are often found in startups and small organizations. The key advantages of the agile model: It adapts to changes more quickly than other SDLC models.
The key difference between Agile vs. Waterfall is that Waterfall breaks down software development into isolated phases that flow into each other, while Agile advocates iterative development cycles in which multiple lifecycle phases can run in parallel.
Agile – The most widely used software development model in the industry due to the fact that it is an incredibly dynamic and flexible project management process.
Currently, the most common SDLC models used in software development include waterfall and agile-based methodologies.
In DevOps and Continuous Delivery, there are still a series of tasks that need to be completed to deliver software. Instead of a structured SDLC, you focus on reducing batch size, creating autonomous vertical teams, and automating your deployment pipeline.
Developing the software and implementing the requirements is obviously the longest and hardest stage of SDLC.
Phase 4: Development
The developers build the code, test, integrate and manage. It is the longest phase of SDLC because all the development takes place in this phase.
Maintenance – Let's Make the Improvements. The last but not least important stage of the SDLC process is the maintenance stage, where the software is already being used by end-users.
Spiral Model Strong Points
Manages risks and develops the system into phases. Changes can be introduced later in the life cycle as well.
Agile Model
The Agile methodology promotes the continuous interaction of the development and testing during the SDLC process of any project. Unlike the waterfall model, the development and testing activities in the agile model are simultaneous.
The spiral model is a systems development lifecycle (SDLC) method used for risk management that combines the iterative development process model with elements of the Waterfall model. The spiral model is used by software engineers and is favored for large, expensive and complicated projects.
There is plenty of supporting evidence that Agile wins out over Waterfall Projects. That data comes from 25 years of studying project success and failure rates is pretty clear. Agile projects are 2X more likely to succeed and less than half as likely to fail than Waterfall.
This model is more flexible – less costly to change scope and requirements. It is easier to test and debug during a smaller iteration. In this model customer can respond to each built. Lowers initial delivery cost.
A software development life cycle (SDLC) is a methodology followed to create high-quality software. By adhering to a standard set of tools, processes, and duties, a software development team can build, design, and develop products that meet or exceed their clients' expectations.
Waterfall model is the simplest model of software development paradigm.
There are two core software development life cycle models: heavyweight (predictive) and lightweight (agile).