Software Development Life Cycle, Phases, Methodologies & Practices Explained!

You're likely to have software installed on the system you simply can't live without. I admit! We all use the software in our everyday routine, but most of us don't care about the processes that help run that software without a hiccup. Have you ever wondered how final software is developed and released into the market? Simply put, SDLC - The software development life cycle - A series of phases that help bridge gaps between the software idea and high-quality structure in the shortest time frame. Excellent software development starts with a great vision in the IT landscape. Like other complex processes, SDLC also takes in-depth planning and preparation at different phases.

You can say SDLC is a structured process that involves planning, designing, developing, testing, deploying, and maintaining software. The development teams out there can use this framework to manufacture the software according to the defined standards. With the essence of delivering high-quality software to the client, SDLC consists of a systematic plan, from inception to the final product release. The solution is produced to exceed the client's expectations in line with a specified budget and timeline.

Having an SDLC in place can help minimize the complexity of developing software from scratch. It's a framework with a series of phases that help convert the idea concept into a fully functional structure. In addition to technical aspects, it also encompasses a process that brings conformity to security measures. One more reason for leveraging the SDLC is to make a proper analysis of project requirements, goals of a software project, and a plan to determine the costs. 

SDLC breaks down itself into seven stages to develop high-quality software. No matter what type of software model you choose, each phase plays a vital role in the development process and is used by every developer. Let's explore the stages one by one and understand each of them with the differences between them. 

The SDLC process starts with the planning stage. It is the first stage that involves identifying the project scope and its requirements to build a comprehensive action plan. Within this phase, you will also get through what will happen throughout the life cycle and determine your project's success factors. From team size, timeframe, budget to so many more, all the elements are focused on in this phase.

Once the planning is finished by the software development company, the concept is in place to perform a deep analysis of the functional requirements so that the software meets the client's expectations. All the expectations of the clients are documented all in one place. The output from the requirement analysis will vary as it all depends on the methodology you use. 

Once the complete analysis is done, and all A to Z requirements are set, the designing phase begins. It involves the design of the system's architecture, its UI and UX, and databases. The system is produced to include all the necessary features that help meet all the software's functional aspects. 

The development phase is the prolonged phase of the software development life cycle. It is executed once the final design is approved from the client. In the fourth phase, the developers' team brings the clean code, technical and physical configurations in work to build an overall system. It is the most robust phase of the process where the most efforts, time, and technical skills are put into.

It's another vital phase of the SDLC process. Without proper testing, it's completely impossible to deliver the software of utmost quality. The testing part is essential to perform for better software quality, functionality, vulnerability, and performance. During this phase, all the errors are detected inside the product and fixed. Only after thorough testing, the product is released into the market. 

The next stage of the SDLC is the product deployment which occurs only after the clear coding and testing of the software. In this step, the bug-free, fully functional, and secure software is finally released or launched for everyone. An end-to-end software is made available to users for download on a system. 

The software development life cycle doesn't stop here and continues with the software's regular monitoring for other errors and upgrades. In this phase, there is a traditional watch on the working of the software to analyze whether it's working correctly or there is a need to add something new. Your software needs to be updated regularly to meet quality standards. 

The waterfall model is the most uncomplicated methodology that is easy to manage but can be prone to some delays. Each of the phases is reviewed before the next starts but can be evaluated for feasibility. Once the one stage is completed and you move the next, nothing can be fixed until the maintenance phase. For the waterfall model to work smoothly, knowing the requirements before the project execution is essential than ever. 

Most of the experts stated that the waterfall model is never meant to be best for real projects. Although it is the oldest methodology and works very straightforward, it's still beneficial for some. This model is not appropriate if flexibility is required in the long-term project. 

The spiral model is considered as one of the most flexible software development life cycle models that also follows repetitive principal waterfall principles. In this model, most of the attention pays to the management of risks. After exploring and handling the risks, the model decides whether to move on to the other phase or not. Each of the projects mainly goes through the four stages, starting from the analysis, designing, building, and risk management.

The benefit of this model is that it allows the building of customized software meeting the business requirements. Unlike other models, the cost might be higher for building the complete product. Ideal for large projects, the spiral model allows multiple rounds of refinement to determine the potential risks. 

It's a repetitive process that rinses and produces continual repeats until the complete system is ready. With the Iterative development model, developers can quickly create a basic prototype of the software because it allows them to review and enhance the software step and step. You can start with implementing the features, test and evaluate them, refine and move forward. 

The whole process is implemented again and again until the viable product is produced. Most often used in large-scale apps, the model can get the app up and running with less hassle and meet the business needs so far. The benefit of such a model is that it is less expensive to implement changes, but the repetition of processes can consume more resources. 

The agile model is next on this list. It is one of the widely used SDLC methodologies specially designed to meet customer needs. This methodology comes with very short iterations. The whole development process is split into a few stages - planning, analysis, design, development, and testing. Each iteration executed within the model delivers enough functionality to satisfy the end-user. 

Businesses in the majority prefer Agile methodology to produce releases regularly. The best part about this methodology is that it helps identify all the minor issues before they cause significant problems. Applying the Agile frame to the most complex development projects proves to be beneficial for many reasons. 

In SDLC, DevOps is considered as the newcomer. Just like the Agile model, this methodology also helps in enhancing the relevancy of apps. In this model, both developers and operational teams develop the most reliable software products with advanced functionalities. DevOps is not only an approach for planning and execution, but the methodology also committed to making projects go through an unexpected challenge. 

The Lean model is completely different from all other models that do not rely on multitasking. This methodology comes with a set of principles that minimizes the programming efforts. All the information can be gathered directly from the source which means the software produced fully satisfies the customer needs. Organizations who are in the need of completing the software in the very shortest time frame can consider this model.

Selecting an ideal SDLC model will require one's careful thought. After all, the SDLC methodology is one of the essential pillars for business success. With all the models discussed above, it is clear that each of them offers a unique process for every project challenge. Your choice for the ideal one heavily depends upon a few parameters like the project's constraints and the people involved in the process.

In addition to some SDLC methodologies, there are some good practices to apply in the software development lifecycle. 

It is one of the most helpful practices used to secure the code is keeping it together all in one location while maintaining a history of changes. All the files can be stored and accessed in some physical or virtual space where only authorized users can log in via an encrypted connection. If the code during the development cycle gets messy, the source control management helps you return to the clean version that offers a quick solution to fix the problems.

Continuous Integration and Continuous Delivery are the SDLC practices designed to produce fast software development. CI merges the coding of software constantly to ensure each component is compatible. At the same time, CD allows frequent deployments within the SDLC pipeline. CI/CD is a combined strategy that allows all internal teams to use the same programming languages to prevent duplicate work.

The process of transforming project requirements into secure software requires an appropriate SDLC model. Because it's likely to miss the issues while coding if there is no detailed plan in place, only using the suitable methodologies and tools can you increase the efficiency, cut down expensive costs, and reduce the risks. With enough knowledge of how to choose the SDLC model, a software development expert will build customized solution with your requirements and make the security practices work for your business.