Iterative SDLC model

iterative sdlc model QaonCloud

What is the Iterative SDLC model?

The iterative methodology, unlike the waterfall model, does not start with fully specified requirements. This process begins with the implementation of a subset of a requirement and slowly enhancing the requirements to evolve multiple versions, thereby developing a complete requirement. Finally, a system development happens through multiple incremental iterations with a review at each cycle.

The different phases in the iterative model are listed below:

Iteration 1

  • 1. Requirement gathering and Analysis Phase

  • 2. Design Phase

  • 3. Coding/Development Phase

  • 4. Testing/Verification Phase

  • 5. Review/Risk Analysis Phase

Iteration 2 Starts
(Repeat steps 1 to 5)

Multiple Iterations occur until the development of system is fully happens. Then the deployment of software happens and goes to the maintenance phase.

The requirements at each iteration are reviewed and enhancement based on the results of the previous iteration.

When to use the Iterative model?

  • The software release needs to happen quickly
  • Large scale projects
  • The final requirements of the software are frozen, but the details may advance with the time
  • Enhancement in each iteration using the requirements, tools, and techniques

Testing Phase in the Iterative software development model

In this model, the testing phase is parallel to the development phase. The iteration starts with gathering and analyzing the requirements. The development occurs in multiple builds, and a testing phase occurs in each build. The testing includes Unit Testing, Integration Testing, and Regression Testing. These test results ensure the stability of the system with each enhancement, and also early detection of errors requires less time to correct and the most cost-effective method. A risk analysis is done at the end of the testing, and then the next iteration starts.

Advantages and Disadvantages


  • Earlier flaw detection as the testing involves in the early stages of development

  • Can accommodate the change of requirements

  • Easy to manage the iterations

  • Cost-effective


  • Requires more supervision on each iteration and each iteration is rigid

  • Not suitable for smaller projects

  • Requires more resources

  • The progress of the project depends on the review/risk analysis of previous iteration

At QAonCloud, We provide testing services based on your SDLC model and your requirements.