SDLC

What is Software Development Life Cycle (SDLC)?

The Software Development Life Cycle (SDLC) is a well-organized process for building software that guarantees the quality and accuracy of the software created. SDLC process intends to deliver high-quality software that meets client expectations. The system development should be finished in the pre-defined time and cost.

Why SDLC?

Here are the best reasons why SDLC is vital for developing a software system.

• It gives a reason for project outlining, scheduling, and budgeting.
• It gives a framework for a conventional set of projects and deliverables.
• It is the best way for project tracking and administration.
• It increases the visibility of project planning to all associated stakeholders thereby helping in the expansion process.
• It helps boost the development speed.
• It also improves client relations.
• It helps you to reduce project risk and project administration plan overhead.

SDLC Phases

During the agile software development life cycle, six specific phases dictate where the project is at any particular point in time, and what comes next in terms of evolution. The various SDLC phases are requirement gathering and analysis, design, implementation or coding, testing, deployment, and support.

Understanding the Different SDLC Phases

Given there are six different software development life cycle phases, it’s important to understand what each phase entails and why it matters to the overall development of the software in question.

The following are the stages of the software development cycle -

• Planning and requirement analysis: Requirement Gathering is the most important stage in SDLC. Business analyst and project organizer do client meeting to gather all the requirements of the clients like what to build, who will be the end-user, what is the purpose of the product, etc. Before creating a product, a core understanding or knowledge of the product is very necessary. 
• Defining requirements: Once the requirement analysis is done, the next stage is to surely document the software specifications and get them approved by the project stakeholders. This can be accomplished through the "SRS"- Software Requirement Specification document, which embraces all the product elements to be created and developed during the project life cycle.
• Designing: In this stage, the requirements gathered in the SRS document is used as information to obtain the software architecture. Moreover, this phase also consists of storyboarding or wireframing software that is needed for functionality. Through this, the developers then create either rough working models, or illustrates how the software will work, how it will look, how usage flows will move from screen to screen, and more.
• Implementation or Coding: In this stage of SDLC, the exact development begins, and the programming is built. The execution of design begins concerning script code. Developers have to follow the coding guidelines defined by their management, and programming tools like compilers, interpreters, debuggers, etc. are used to generate and implement the code
• Testing: After the code is generated, it is tested against the specifications to ensure that the products are solving the needs directed and inferred during the requirements stage. During this phase, several testing like unit testing, integration testing, system testing, and approval testing are done.
• Deployment: Once the software is approved, and no bugs or errors are asserted, then it is deployed. Later, based on the assessment, the software is delivered as it is or with suggested augmentation in the object segment. After the software is deployed, then its sustenance begins.
• Maintenance: Once the client starts using the developed software, then the real issues start coming up. In this stage, the team is required to fix the issues, roll out new features and refine the functionalities as required. The method where the care is taken for the finished product is thus known as maintenance.

The Role of the SDLC Phases

There can be some crossover or blurring of the lines in many of the SDLC phases, but the importance of each phase as a distinct element in the overall life cycle cannot be denied. Without a full analysis of the customer’s needs or the requirements for the software or app, necessary functionality and needed features, design and development cannot proceed.

Without accurate design work beforehand, the software cannot be developed. Without skilled developers on the project, the development will be slow or fraught with problems. Without being able to accurately test software or an app, bugs could slip through that would compromise operability and stability. It’s all interconnected.

Popular SDLC models

Here are some of the most important models of Software development life cycle:

• Waterfall model - The Waterfall is a widely trusted SDLC model. In this linear sequential model, the whole process of software development is divided into various phases.
• Incremental Approach - The Incremental model is not separate. It is a series of waterfall cycles. The elements are divided into groups at the commencement of the project. For each group, the SDLC model is followed to produce software. 
• V-Model - This type of SDLC model is used for testing and development. The phase is planned in parallel. So, there are verifying stages on one side and the validation phase on the other side. 

Apart from the above mentioned, there are other popular models like the agile model, spiral model, and the big bang model.

In short, the software development life cycle describes a methodology for advancing the quality of software and the overall software development method.