Understanding the Software Development Life Cycle:

To develop the best possible software in the most efficient manner is no easy feat.

Complex software development projects may take tens or hundreds of hours to complete and require extensive testing and revising once the project is complete.

Without a solid framework to manage such a monumental task, financial and time-related costs can get vastly out of control, leading to an unpleasant situation for both the client and developer(s).

It’s highly recommended for a software development team to develop and adhere to an effective software development checklist to streamline the development process.

Creating and executing such a checklist begins with a clear understanding of the software development life cycle.

What is the Software Development Life Cycle (SDLC)?

The software development lifecycle describes the sequence of events that transpire throughout a software development project from planning all the way through to maintenance.

This in-depth process is associated with several models, each including its own set of tasks and activities.

Software development requires a tremendous amount of planning, starting with the proper identification of project requirements, their implementation, and deployment measures.

But of course, the strenuous process of software development doesn’t end there.

After the deployment phase, software developers must provide proper, timely maintenance services to ensure that the software works optimally.

Because the SDLC offers a basis for software development project planning, scheduling, and estimating deliverables, the process has been broken down into phases.

What Are the Phases of the Software Development Life Cycle?

The entire SDLC life cycle is divided into these seven phases:

1. Requirement Extraction & Analysis

2. Feasibility Analysis

3. Architectural Design

4. Building & Coding

5. Testing

6. Installation & Deployment

7. Maintenance

All of these phases must be executed in sequential order for the project to prove successful.

Any skipping, skimming, or half-measures will result in programming errors that can become expensive, frustrating, and discouraging to the client.

Phase 1: Requirement Extraction & Analysis

The first stage of the SDLC process is the requirement extraction & analysis phase.

This is where senior software development team members and domain experts plan for quality assurance requirements and recognize the risks involved during the development process.

The best course of action to take whenever beginning a software project is to team up with highly experienced developers who understand the project requirements’ ins and outs.

You wouldn’t hire a first-year law student to defend you in a court of law, would you? No, we didn’t think so.

Amid a lawsuit, you’d want to hire an attorney with the most experience and professional success that you could find, right?

Well, the same goes for software development.

This stage presents a clear picture of the entire software project’s scope, along with its anticipated roadblocks, opportunities, and directives.

Phase 1 also helps companies finalize the timeline to finish the work once they’ve established the details and precise requirements.

From there, we move onto the second phase of the SDLC - the feasibility phase.

Phase 2: Feasibility Phase

Once your team has completed the requirement & analysis phase, it’s time to define and document your software needs.

The feasibility process includes everything that should be designed and developed during the SDLC.

There are five types of checks involved in the feasibility phase:

1. Economic

2. Legal

3. Operational

4. Technical

5. Schedule

This process is conducted with the help of the Software Requirement Specification document, also known as the SRS document.

Phase 3: Architectural Design

During this phase, the software design is prepared as per the SRS document, which also serves as input for the fourth phase of the life cycle.

The design plan, or Design Specification, incorporates a collection of the stakeholder’s input, which is then followed by their feedback to improve upon the system.

There are two kinds of design documents that are developed during phase 3:

High-Level Design (HLD)

High-level designs incorporate the name and a brief description of each module. They showcase the complete architectural diagrams next to technical details and essential elements.

These designs also include the interface relationship and dependencies between the modules and identifiable database tables.

Low-Level Design (LLD)

Low-level designs describe the complete input and output for each of the modules, along with explanations addressing all types of dependency issues.

This document includes a thorough listing of error messages, functional module logic, details of the interface, and the database tables’ type and size.

Phase 4: Building & Coding

Now we arrive at phase 4 - where the magic happens.

In the building and coding phase, developers build the entire system by writing code in a specific programming language, such as JavaScript or Python.

Phase 4, the development phase, is the longest in the life cycle, and for a good reason!

Typically, tasks are divided into modules or units and are then assigned to different developers to execute as part of the collaborative effort.

Developers leverage different programming tools, including compilers, debuggers, interpreters, and others, to generate and implement the code.

Developers must define and establish a file nomenclature, as it will help their team produce organized, consistent code that’s testable during the next development phase.

Phase 5: Testing

Once the developers have finished the coding, it’s time to test it out!

During the testing phase, the software is deployed in the testing environment, where a quality assurance team tests its functionality.

This is where QA and testing teams find bugs and defects within the system. They then communicate these issues with the developers so that they can apply a solution to the problem.

The testing process continues as long as it takes to ensure that the software is stable, bug-free, and has no defects.

Once everything has been tested and proved to be in perfect working condition, developers move into the next development phase.

Phase 6: Installation & Deployment

The goal for this phase is to deploy the software to the production environment for distribution purposes.

Some stakeholders prefer to deploy the product in a testing or staging environment first before showcasing it to the public.

This allows stakeholders to play with the product before releasing it, allowing for any final edits to be made.

Phase 7: Software Maintenance

Just because a new system has been deployed and distributed to the masses, it doesn’t mean that all work is finished.

Just like any piece of technology, software requires maintenance and upkeep.

For example, software updates must be performed regularly to ensure optimal performance.

Sometimes, testers miss things, and they have to go back and fix bugs and other relevant errors after the deployment phase.

Stakeholders also decide later on that they wish to add new features to the system, which of course, must be implemented by a team of developers.

The primary focus of this phase is to ensure that the software system performs as per the specifications mentioned in phase 1: requirement extraction & analysis.

What Are the SDLC Models?

There are several SDLC models, followed during the software development process. Each process follows a series of unique steps that developers go through to ensure a successful outcome.

Here are a few of the most popular SDLC models to choose from:

Waterfall Model

The waterfall model is a classic approach to software development. In this methodology, developers finish one phase and then move onto the next.

Each phase involves its own detailed plan, and then each phase spills over or “waterfalls” into the next phase to ensure that each phase is completed before moving on to the phase that proceeds it.

A significant advantage of the waterfall model is that each phase can be thoroughly evaluated for feasibility and continuity before moving onto the next phase.

However, if something goes wrong in a particular phase, it can drastically slow things down in terms of moving forward. Skipping phases isn’t allowed in this model.

Developers who follow the waterfall model must finish a phase before moving on, no matter what.

Agile Model

What’s great about the agile model is that it was designed with the client in mind. This methodology strongly focuses on input and user experience.

Using this customer/client feedback is an essential part of the process, as it makes the software much more user-friendly in the end.

In response to an ever-changing market, the agile model also promotes a quicker release of these software cycles.

The only drawback with the agile model is that the project will typically rely heavily on customer feedback, which can lead to a project going off-track or take longer to deploy.

Prototyping Model

In this methodology, the developers create prototypes or incomplete sample versions of the software.

This is an effective model because it helps developers test the process more accurately and visualize the components.

There are four types of prototyping, including evolutionary, incremental, throwaway, and extreme prototyping.

This model tends to be time-consuming, resulting in delayed deployment times. Although this could result in an unhappy client, it could prove useful to develop a prototype if the software warrants it.

Spiral Model

The spiral model is the most flexible of the SDLC models, which involves planning, designing, coding, and QA testing phases multiple times with gradual improvements after each pass.

This risk-driven process model helps development teams adopt the elements of both the prototyping and waterfall models.

The spiral methodology is a unique combination of rapid prototyping and developmental concurrency.

Big Bang Model

Unlike the other SDLC models, the big bang model requires no or very little planning. This methodology focuses on software development resources and coding practices, with developers understanding and implementing the requirements as they come.

This model is most effective when working on smaller projects and a small team of developers. It has also proven useful when deploying academic software development projects.

For developers and stakeholders who have a vague list of requirements and an unknown release date, the big bang model is the most pragmatic solution to achieve success.

In Conclusion

When it comes to your unique software project, don’t rely on amateurs. Hire a team of experienced, dedicated, and trusted software developers and engineers to ensure that your project is completed promptly.

Chetu has been providing best-in-class software development services for over 22 years. Our team consists of 2,800 developers who have in-depth, industry-specific experience.

We’ve been developing, implementing, integrating, configuring, and programming custom software solutions successfully for a wide variety of businesses and industries.

We understand every aspect of the software development life cycle and practice the principles mentioned in this article every day.