Incremental Model in Software Engineering

In this article, we will discuss What is incremental model? When to use incremental model? and also discuss the advantages and disadvantages of incremental model?

What is the Incremental Model?

In the Incremental model, we do not develop the full software in a single go, instead first, we break down the customer’s requirements into multiple standalone modules and then develop each module one-by-one (like a mini project) using the waterfall approach and increment each module with the previous modules.

So in this model, the whole software project developed module-by-module and incremented to the previous module.

First, the development team develops the core module of the software project and after that other modules are developed one-by-one, and each module is increment with the core module and so on.

Core module means first the developers develop the highest priority requirements. So when first the core module is developed, it delivered to the customer, so the customer can use it and give us the feedback of the developed software. After that other modules are developed one-by-one and incremented to the core module, and delivered to the customer after each increment.

This module is used, when requirements are well-understood, means the customer known what he wants to develop.

In this phase, all the customers’ requirements are collected at the starting of the project, and SRS documents are created in the starting phase after that we develop and increment software module-by-module according to the customer’s requirements.

Incremental model image

 

When to use Incremental models?

  • This model can be used when the requirements are clearly defined and well understood.
  • When the customer knows his exact requirements.
  • When the product has to deliver in the market early.
  • When the customer demands a quick release of the product.
  • When the project has a lengthy development schedule.
  • When the project is large and some high-risk features and goals.
  • When a new technology is being used and also the software team is new to this new technology.

Advantages of Incremental Model

  • Customer Interaction Maximum: Customer interaction maximum because in every increment, the product delivered to the customer.
  • Initial product delivery is faster: The product can be delivered at the initial stage so the customer can use the product early and gives us the proper feedback.
  • Lowers initial delivery cost: Initially, product cost is low, because the product is delivered increment-by-increment, so the customer does not have to pay all costs initially.
  • Early customer feedback: With every release of the product, the customer can give us feedback, which helps the developers to the next module.
  • More Flexible: This model is more flexible because the product developed in stages, so the company does not have to use all of its cost & manpower, and also because of customer’s feedback, the company knows, what the actual customer expectations from the product, so they can full the customer’s requirements in the next product release.

Disadvantages of Incremental model

  • This model is used when the requirements are well understood, so it needs good and effective planning.
  • It needs more cost and also needs more time.

Summary of Incremental model

  • All the requirements of the customer are collected at the starting of the software project and written in the SRS documents.
  • A whole software project is broken down into modules.
  • Every module develops like a mini project using a waterfall approach
  • First, the development team develops the core module of the system and after it develops other modules one-by-one.
  • When one module is developed that module is incremented in the core module and so on.
  • Every module increment to the previous module and delivered to the customer every time.

Also Read: SDLC (Software Development Life Cycle)