Iterative Model in Software Engineering

In this Model, you can start with some of the software specifications and develop the first version of the software. After the first version, if there is a need to change the software, a new version is created with a new iteration. Every release of the Iterative Model finishes in an exact and fixed period called iteration.
The Iterative Model allows the accessing of earlier phases, in which the variations are made respectively. The project’s final output was renewed at the end of the Software Development Life Cycle (SDLC) process.
The Iterative Model, also known as the Iterative Development Model, is a software development process model emphasizing a cyclic, repeated approach to building software systems. It is one of the many software development methodologies used in software engineering. The Iterative Model is often contrasted with the Waterfall Model, a linear and sequential approach to software development.
Here are the key characteristics and principles of the Iterative Model in software engineering:
  1. Repetitive Cycles: The software development process is divided into small, manageable iterations in the Iterative Model. Each iteration represents a complete development cycle that includes planning, designing, coding, testing, and reviewing.
  2. Incremental Development: A portion of the software system is built or enhanced during each iteration. These step up can be new features, enhancements to existing features, or bug fixes. Over time, as multiple iterations are completed, the software gradually evolves and improves.
  3. Feedback and Evaluation: At the end of each iteration, there is an analysis and evaluation phase. Stakeholders, including customers and developers, assess the work done in the iteration. This feedback is used to make necessary adjustments to the project requirements, design, and development plan.
  4. Flexibility: The Iterative Model is highly flexible and adaptive. It allows for changes in requirements, technology, and design as the project progresses. This flexibility is beneficial when the project requirements are not well-defined initially.
  5. Risk Management: By addressing critical and high-risk components early in the development process and refining them through successive iterations, the Iterative Model helps manage project risks effectively.
  6. Customer Involvement: Customers or end-users are actively involved in the development process. They provide feedback after each iteration, which helps ensure that the software meets their evolving needs and expectations.
  7. Phases Within Each Iteration: Each iteration follows a mini Waterfall-like process with stages such as requirements analysis, design, implementation, testing, and deployment. These phases are repeated in each iteration.
  8. Integration and Testing: As the software evolves through multiple iterations, integration testing is performed at each stage to ensure the individual increments work together cohesively.
  9. Completion Criteria: Each iteration has its own set of completion criteria, which define when an iteration is considered finished and ready for review.
  10. Example Frameworks: Some popular software development frameworks that follow the Iterative Model include the Rational Unified Process (RUP) and the Unified Process (UP).

Benefits of the Iterative Model:

  • Allows for flexibility and adaptation to changing requirements.
  • Frequent feedback from stakeholders helps in aligning the software with user needs.
  • Early identification and mitigation of project risks.
  • Incremental delivery of working software, which can be valuable for customers.
  • Easier management of complex projects.

Challenges of the Iterative Model:

  • Requires continuous involvement and feedback from customers, which can be resource-intensive.
  • Managing multiple iterations and keeping track of changes can be complex.
  • The success of the Model relies on effective communication and collaboration among project stakeholders.
The Iterative Model is particularly suitable for projects where requirements are uncertain, and there is a need for frequent interaction with customers or end-users. It is commonly used in agile methodologies like Scrum and Kanban, emphasizing iterative and incremental development practices.

In this Software Testing Tutorial, we will learn about the iterative model in software engineering. The iterative development model was again the improvement over the waterfall and V model in order to address the delay in feedback loop.

When we follow longer development cycles then the feedback from customer is delayed as they only see the actual working software after long development cycle.

In order to overcome this iterative development approach came in picture where the smaller development cycles were repeated in order to get quick feedback from customer after each iteration.