What is meant by models of Software Engineering and types of models of Software Development?

Models of Software Engineering:

Models are a common sort of description used in the software development process. They’re abstractions that help developers deal with the complexity of the problem or solution they’re working on by expressing and communicating what’s important while avoiding unnecessary detail. Modeling is used in several areas of design and engineering.

The various methods or approaches chosen for project development depending on the project’s aims and goals are referred to as software development models. To satisfy varied requirements, multiple development life cycle models have been developed. The models outline the process’s numerous phases as well as the order in which they must be accomplished.

The model chosen has a considerable impact on the testing that is conducted. It will establish the what, where, and when of our intended testing, as well as the impact of regression testing and the test techniques to be used.

All software development models may be classified based on how they manage workflow organization – linearly or iteratively – and the types of interactions generated between the development team and the customer.

Types of the model of software engineering:

Waterfall model:

The Waterfall Model is a sequential flow that takes a straight line. In which the steps of software construction are portrayed as flowing smoothly downwards (like a cascade). This means that each stage in the development process may begin only after the one before it has concluded. The waterfall approach does not describe how to return to a previous phase to handle needs changes. The waterfall approach was the earliest and most well-known software development method.

Usage:

Projects that do not focus on changing needs, such as those initiated in response to a request for proposals (RFPs) and where the client has extremely well-documented specifications.

V-shaped model:

Instead of flowing down in a linear fashion as in the waterfall model, the process steps are twisted upwards following the implementation and coding phases, generating the typical V shape. The key distinction between the V-shaped model and the waterfall model is the early test planning in the V-shaped model.

Usage:

• Software requirements are well-defined and well-understood.
• The technologies and tools used in software development are well-known.

Incremental model:

It is critical to understand that the incremental approach is not a standalone model. A series of waterfall cycles cannot be avoided. The needs are divided into groups at the outset of the project. Each group’s software is built using the SDLC approach. The SDLC process is repeated until all requirements are met, with each release increasing capacity. In this strategy, each cycle serves as a maintenance interval for the previous software release. The gradual technique has been updated to allow for overlapping development cycles. Following that, a new cycle may begin before the previous one has been completed.

RAD model:

The Rapid Application Development (RAD) technique is a waterfall model adaption that focuses on rapidly developing software. The RAD method is based on the premise that by acquiring system needs through focus groups, a better system may be built in less time.

RAD model has the following phases:

• Business modeling
• Data modeling
• Process modeling
• Application generation
• Testing and turnover

Agile model:

The phrase “agile process model” refers to an iterative software development strategy in which projects are broken into smaller iterations or sections and long-term planning is ignored. The project’s scope and requirements are set at the start of the development process. The number of iterations, length, and scope of each iteration are all specified in advance.

Each iteration in the Agile process paradigm is a short-term “frame” that can span anywhere from one to four weeks. The division of the entire project into smaller pieces aids in reducing total project delivery time requirements while reducing project risk. Each iteration needs a team to go through the whole software development life cycle, which includes planning, requirements analysis, design, coding, and testing, before presenting a working product to the customer.

Agile thinking emerged early in software development and expanded in favor over time due to its flexibility and adaptability.

Some of the most well-known Agile approaches include Rational Unified Process (1994), Scrum (1995), Crystal Clear, Extreme Programming (1996), Adaptive Software Development, Feature Driven Development, and Dynamic Systems Development Method (DSDM) (1995). Following the 2001 publication of the Agile Manifesto, these are now known as Agile Methodologies.

Iterative model:

The iterative process begins with a primitive implementation of a small set of software requirements and continuously improves the evolving versions until the full system is finished and ready for deployment.

Iterative life cycle models do not start with a complete set of requirements. Rather, development starts with the definition and execution of a tiny section of the software, which is then assessed to identify further needs. The iterative model procedure is then repeated, with each model iteration resulting in a new version of the software.

You can begin with minimal software specifications and also use the Iterative Model to construct the first version of the software. If the program has to be altered after the initial version, a new version of the software with a new iteration is created. Every Iterative Model iteration is done within a specific time range.

The Iterative Model allows you to return to previous phases and also examine how modifications were implemented. The project’s final product was refreshed at the conclusion of the Software Development Life Cycle (SDLC) method.

Spiral model:

The spiral model is one of the most prominent Software Development Life Cycle models for risk management. In diagrammatic form, the spiral model resembles a spiral with numerous loops. The exact number of loops in the spiral is unknown, and it changes from project to project. Each loop of the spiral represents a Phase in the software development process. The project manager may adjust the number of phases necessary to deliver the product depending on the project risks. Because the number of phases is always decided by the project manager, the project manager plays an important role in producing a product using the spiral model.

Prototype model:

Rather than freezing requirements before proceeding with design or coding, the Prototype technique develops a throwaway prototype to gain a better understanding of the needs. This prototype concept is based on currently recognized needs. A prototype model is a software development approach. Interacting with the prototype allows the client to get a “genuine feel” for the system since interactions with the prototype can assist the customer in better understanding the needs of the planned system. When there is no manual technique or existing system to assist in developing requirements, prototyping is an appealing idea for complex and large systems.

The prototype model is frequently not a complete system, and many of the complexities are not included. The goal is to develop a system that is generally functioning.