Software Development Life Cycle (SDLC) Explained

Post date :

Jan 30, 2024

Have you ever experienced the frustration of investing time and resources into a software project, only to encounter bugs and functionality issues post-launch? It's a common challenge in software development that often stems from a lack of structured planning and execution.

Consider the aftermath of a poorly managed software project – customer dissatisfaction, increased costs due to fixing errors, and missed opportunities in the market. Without a systematic approach like the Software Development Life Cycle (SDLC), these issues persist, hindering success and causing setbacks.

What is SDLC?

The SDLC is the roadmap for creating software, ensuring efficiency and quality. It breaks down the entire process into distinct phases: planning, design, development, testing, deployment, and maintenance. By following this structured approach, developers streamline processes, reduce errors, ensure quality, leading to cost savings and quicker time-to-market, and deliver software that meets user needs effectively.

Understanding and implementing the SDLC methodology is crucial for anyone aspiring to excel in software development. It's the key to crafting robust, error-free software that resonates with users and stands out in the market.

Understanding and implementing the SDLC methodology is crucial for anyone aspiring to excel in software development. It's the key to crafting robust, error-free software that resonates with users and stands out in the market.

Why is SDLC important?

Navigating the complexities of software development poses unique challenges: evolving requirements, technological advancements, and the intricacies of cross-functional teamwork. The SDLC method ensures consensus among stakeholders from the outset, establishing a unified vision for software development goals. Moreover, it crafts a strategic roadmap, enabling a clear and cohesive plan to bring these shared objectives to fruition.

Here are six benefits of the SDLC methodology:

  1. Helps in organizing tasks, reducing errors, and ensuring smoother progress.

  2. Ensures that the software meets quality standards, functions correctly, and satisfies user requirements.

  3. Helps in identifying and mitigating risks early in the development process. 

  4. More predictable timelines and cost control throughout the project lifecycle.

  5. It facilitates better communication among teams, stakeholders, and clients by providing a structured framework that everyone can understand and follow.

  6. The SDLC can be tailored to fit different project sizes, types, and methodologies. This adaptability allows teams to adjust the process based on project requirements, making it scalable for diverse software development needs.

How does SDLC work?

As you know now, the SDLC breaks down the development process into distinct phases – planning, designing, development, testing, deployment, and maintenance. This section digs deeper into each phase.


In this initial phase, project goals, requirements, and constraints are defined. It involves gathering information, analyzing feasibility, creating a project roadmap, and establishing a project plan. Key tasks include defining scope, setting objectives, allocating resources, and creating a timeline.

Analysis sub-phase

During this sub-phase, a detailed study of the project requirements is conducted. It involves understanding end-user needs, gathering specific requirements, and documenting functionalities that the software should deliver. Analysts work closely with stakeholders to ensure all requirements are captured accurately.


The design phase involves creating a blueprint for the software based on the gathered requirements. It includes architectural design, system design, and user interface design. The goal is to create a comprehensive plan that outlines how different components will work together to fulfill the specified requirements.


This phase involves the actual development of the software. Developers write code based on the design specifications from the previous phase. It's where the software begins to take shape. This stage includes coding, unit testing, and integration of various components to form a complete system.


Testing is a critical phase where the software is rigorously checked for bugs, errors, and functionality issues. Different types of testing, such as unit testing, integration testing, system testing, and user acceptance testing (UAT), are performed to ensure the software meets quality standards and functions as intended.


Once the software has been thoroughly tested and validated, it's ready for deployment or release. This phase involves installing the software in the live environment, making it accessible to end-users. Deployment strategies and plans are executed to ensure a smooth transition from development to production.


After deployment, the software enters the maintenance phase. It involves addressing issues reported by users, making necessary updates, fixing bugs, and enhancing features. Maintenance ensures the software remains functional, secure, and aligned with evolving user needs.

How does SDLC address security?

Today, cyber security is an integral part of the software development lifecycle. You should address security throughout the SDLC by following DevSecOps best practices and conducting security assessments. This section looks at the stages of the SDLC from a cybersecurity perspective.

Planning and Analysis: During the early stages, security requirements are identified. This involves understanding potential threats, compliance needs, and security features necessary for the software. By defining security requirements upfront, developers can integrate security measures into the design and development phases.

Design Phase: Security considerations are embedded into the architectural design. This includes implementing secure design principles, such as least privilege access, data encryption, and secure communication protocols. Threat modeling is also performed to anticipate potential vulnerabilities and plan mitigation strategies.

Implementation and Coding: Developers follow secure coding practices to reduce vulnerabilities. This involves using secure coding standards, input validation techniques, and avoiding common coding mistakes that can lead to security vulnerabilities like SQL injection or cross-site scripting (XSS).

Testing: Security testing is a crucial part of the SDLC. It includes various types of testing such as penetration testing, vulnerability assessment, and security scanning. These tests identify and rectify security flaws, ensuring the software is resilient against attacks and complies with security standards.

Deployment: Before deployment, a final security assessment is often conducted to ensure that the software meets security standards and compliance requirements. Secure configuration practices are applied to servers, networks, and other components involved in the deployment process.

Maintenance: Ongoing maintenance involves patching known vulnerabilities, updating security measures, and monitoring the software for emerging threats. Incident response plans are put in place to address any security breaches or vulnerabilities discovered post-deployment.

What are SDLC Models?

There are different ways of arranging the SDLC

Waterfall Model:

The Waterfall model is a linear and sequential approach where each phase flows in a downward direction, like a waterfall. It progresses through distinct stages such as requirements gathering, design, implementation, testing, deployment, and maintenance. Once a phase is completed, the next phase begins. This model is rigid and requires clear and well-defined requirements upfront, making changes difficult once the process moves forward.

V-Shaped Model:

The V-shaped model is an extension of the Waterfall model with a strong emphasis on testing. Each development phase has a corresponding testing phase, forming a "V" shape. It emphasizes verification and validation at each stage of development. This model ensures that testing is incorporated early in the process, reducing the likelihood of major issues discovered late in the cycle.

Iterative Model:

The Iterative model involves breaking down the software development process into smaller cycles or iterations. Each iteration encompasses the phases of the Waterfall model but allows for revisiting and refining each phase iteratively. This model allows for flexibility and iteration based on feedback, making it easier to accommodate changes.

Spiral Model:

The Spiral model combines iterative development with elements of the Waterfall model. It involves repeated cycles, each of which includes planning, risk analysis, engineering, and evaluation. It emphasizes risk management by addressing potential risks and uncertainties throughout the development process. The Spiral model is particularly useful for large, complex projects where risks need continuous evaluation and mitigation.

Agile Model:

Agile is an iterative and flexible approach focused on collaboration, adaptability, and customer involvement. It emphasizes delivering functional software in short iterations called sprints. Agile methodologies, such as Scrum or Kanban, prioritize frequent feedback, allowing for changes based on customer needs or evolving requirements. It values individuals and interactions over rigid processes and tools.

Big Bang Model:

The Big Bang model is an unconventional approach where there is no specific process or sequence. It involves starting development without clear requirements or a structured plan, often due to urgent or rapidly changing needs. The development progresses chaotically, and the entire system is developed simultaneously without predefined phases.

Each SDLC model has its strengths and weaknesses, and the choice of model depends on project requirements, complexity, flexibility needed, and the ability to accommodate changes during the development process. Different projects may benefit from different models based on their specific needs and constraints.

Software Development Bootcamp with UBC Extended Learning

Become a software developer in only 36 weeks. This Bootcamp equips learners to become well-rounded software developers, aligning their skills directly with current market trends and demands. By covering everything from foundational web basics to advanced front-end and back-end development skills, including system design and mobile development, we ensure bootcamp graduates stand out in today’s competitive landscape. 

Ready to conquer the challenges of software development? Join our Bootcamp today.

© Circuit Stream.
This course is delivered by Circuit Stream in partnership with UBC Extended Learning.

© Circuit Stream. This course is delivered by
Circuit Stream in partnership with
UBC Extended Learning.

© Circuit Stream.
This course is delivered by Circuit Stream in partnership with UBC Extended Learning.