Software development projects begin with the decision of which methodology to use. Generally, a development methodology is a simple method for organizing your work. The Waterfall methodology manages a project linearly from start to finish. Engineers often use a front-loaded method. It relies on thorough planning, detailed documentation, and consecutive execution of the project. You will likely hear from a new-age developer that Waterfall is dead. Organizations continue to use the Waterfall methodology due to traditional development environments. The iterative Waterfall model comes with unique requirements, advantages, and challenges. Let us look at the Waterfall methodology and phases in detail.

What is The Waterfall Model?

A Waterfall model divides software development into predefined phases. The phases must be completed independently and without overlap. During the SDLC phase, each phase performs a specific activity. Winston Royce made it popular in 1970.

Who applies the Waterfall model?

Project managers adopt the Waterfall approach when dealing with development projects that:

  • Avoid ambiguous requirements.
  • Be clear about what will happen from the beginning.
  • Once a project is underway, clients are unlikely to change its scope.

Project managers may want defined processes that outline cost, time, and design requirements. The Waterfall method is the best choice when the project meets those constraints.

Waterfall Model Software Development Life Cycle

According to the Waterfall methodology, requirements, dates, and outcomes are fixed. The Waterfall model is ideal for execution teams. Since they are usually self-contained and don’t need to communicate constantly.

Team members work independently and report status less frequently. An orderly process begins with the completion of the previous phase. Software development projects usually follow the iterative Waterfall model as follows:

1. Requirements Gathering

In Waterfall methodology, every requirement for the project is gathered and understood up-front. The project manager performs deep research to understand the client’s requirements. The project requirements for each stage include costs, risks, success metrics, and schedules.

Example: 

After analyzing the client’s requirements, the developer checks the new reservation system supports more than one language. What is the expected number of active users in a minute? Etc.

2. Design

Developers create technical solutions such as models and layouts to meet client requirements. The first step is to create a high-level or logical design. It describes the project’s purpose, goals, flow, and integration points. It is transformed into a physical design using hardware and software technologies.

Example: 

The team’s senior members discuss the system architecture, low-level and high-level design together. During this process, developers would discuss redundant backup and failover capabilities. Thereby it ensures system availability at all times.

3. Implementation

Technical implementation follows the completion of the design. As a result of the thorough research and design, the Waterfall process might be the shortest. This phase involves programming applications according to specifications and requirements, testing, and implementation. It may be necessary to revisit the design phase if significant changes are needed.

Example:

The developer incorporates for smooth application function. It includes security checks, audit logging, etc.,

4. Testing

It is necessary to test a product before releasing it to customers to ensure there are no errors. The completion of all requirements ensured a good user experience. The testing team will create test cases based on the design, personas, and use case scenarios. The product manager provides test cases.

Example:

 As part of the project, app domain-specific testers tested the reservation functionality. Security teams examined the application’s security.

5. Deployment 

When the software passes all tests, the user installs it (released to the market). The deployment process involves installing, migrating, and supporting the system in the customer’s or user’s environment. Customer satisfaction will increase, which will reduce maintenance costs. Thus the results will be more accurate due to the improved output. This phase tests the interactions between modules and the system. This step requires you to ensure the environment is running all test exit conditions. Ensure the application functionality by performing sanity checks on the deployment environment.

Example: 

Coordination between the network and IT administration teams is necessary. It supports setting up and running the reservation system.

6. Maintenance

Product development cycles must include regular maintenance and checks. The Waterfall model concludes with maintenance. Modifications are performed immediately after installation. It includes enhancing, changing, or modifying the system’s operation. Client environments present some complications. Patches are available to address these vulnerabilities. Whenever a product is improved, a new version is released.

Example: 

Reservation systems have various features, such as booking, payments, and filters. You must maintain these sections to avoid any glitches in the live application.

Waterfall Model – Advantages

A Waterfall development model offers departmentalization and control benefits. Each stage of development can have a deadline, and the product can go through each phase as it is developed. The development process includes concept, design, implementation, testing, installation, troubleshooting, maintenance, and operation. The phases of development proceed in strict order. The Waterfall Model has the following major advantages.

  • User-friendly and simple to understand
  • The rigidity of the model makes it easy to manage. Deliverables and review processes are specific to each phase.
  • Every phase involves completing one step.
  • It works well for smaller projects with clearly defined requirements.
  • The stages are absolutely defined.
  • A clear understanding of milestones.
  • Tasks are easy to arrange.
  • Well-documented processes and results.

Waterfall Model – Disadvantages

Waterfall development has the disadvantage of allowing little reflection or revision. After testing, changing an undocumented or unthought-through idea takes a lot of work. Waterfall has the following major disadvantages: 

  • It takes a long time to work on software production.
  • There is a high degree of risk and uncertainty.
  • This model is not suitable for complex, object-oriented projects.
  • Long-term and ongoing projects need to be better suited to this model.
  • Incompatible with projects with moderate to high change risks. In this process model, risk and uncertainty are high.
  • Stage-by-stage progress is difficult to measure.
  • Incapable of accommodating changing needs.
  • Changing the scope of a project during its life cycle can lead to its termination.
  • The integration process is a “big bang in the end.” It prevents the early identification of technological or business bottlenecks.

Conclusion

In this blog, we discussed the Waterfall model from different perspectives. Small software development projects are better suited to this approach than large projects. Small projects are easier to design, develop, and implement. It entails completing all previous phases before moving on to the next. That’s why big software development projects are unlikely to use it. The Waterfall model is still necessary for smaller projects. However, most of the projects use Agile approaches now. A Waterfall model will be most effective if testing is straightforward.