A COMPREHENSIVE OVERVIEW

OF SOFTWARE DEVELOPMENT
LIFE CYCLES
By : Anshuman Mridul Sharma
SOFTWARE DEVELOPMENT LIFE CYCLE : AN INTRODUCTION

The Software Development Life Cycle (SDLC) is a structured framework that defines the process of
planning, creating, testing, deploying, and maintaining software applications. It acts as a roadmap, guiding the
entire software development journey from conception to post-launch.

PHASES OF A SOFTWARE DEVELOPMENT LIFE CYCLE

Planning : In this phase the project scope, goals, resources, and timeline are defined to
set the stage for development.

Analysis : In this phase the team gathers and analyses user requirements to
understand what the software needs to do.

Design : In this phase the team translates user requirements into a technical
blueprint outlining the software's architecture and functionality.

Implementation : In this phase the focus shifts from building the software to
deploying it in the real world and ensuring users can effectively utilize it.

Testing : In this phase the software is rigorously evaluated to identify and fix bugs
and ensure it meets all requirements.

Maintenance : In this phase software receives ongoing support, bug fixes, updates, and
potential new features to ensure its functionality and adaptation to evolving needs.
SOFTWARE DEVELOPMENT LIFE CYCLE : PLANNING STAGE

The planning phase is the foundation of the SDLC, where the project takes shape. It involves defining the
software's purpose, outlining clear goals and objectives, estimating timelines and resource allocation, and
establishing a roadmap for the entire development journey. This crucial phase ensures everyone involved is on
the same page from the very beginning.

OUTLINE OF THE PLANNING PHASE

• Identify the problem the software solves. • Identify potential risks (resource constraints, technical
challenges).
• Prioritize core features for initial launch. Risk
Defining • Develop mitigation strategies for each risk.
• Set clear deliverables and acceptance criteria. Management
Project Scope

• Identify project stakeholders (clients, developers, users).

• Craft SMART goals aligned with business objectives.
Communication • Establish clear communication channels for each group.
Goal Setting & • Define metrics to track progress (user adoption, KPIs, etc.). Strategy
Success Metrics

• Select tools to track progress, manage tasks, & facilitate

• Estimate development time and resources (WBS, project tools). communication.
• Assemble a skilled development team. Project • Define processes for decision-making, change management, &
Project Management
• Develop a realistic project budget. Tools & Processes
version control.
Estimation
SOFTWARE DEVELOPMENT LIFE CYCLE : ANALYSIS STAGE

We gather requirements through user interviews, workshops, and existing systems to understand what the
software should do. This includes both the specific functionalities (functional requirements) and how it should
feel to use it (non-functional requirements). By prioritizing these needs based on their importance and business
goals, we ensure we're building the right software.

OUTLINE OF THE ANALYSIS PHASE

• Conduct user interviews: One-on-one sessions to delve into user • Create detailed use cases for key
workflows, challenges, and expectations. functionalities, outlining: Actors involved
Gather • Analyze user stories: Narratives capturing user interactions with the (users, external systems), steps taken by each
Requirements software and desired functionalities. Develop Use actor to achieve a specific goal, Preconditions
Cases and postconditions for each use case

• Functional Requirements : Specific actions the software should perform.

• Non-Functional Requirements : Performance, security, usability, and
Define Functional
& Non-Functional maintainability considerations. • Develop a Software Requirements Specification
Requirements
(SRS) document, a comprehensive record of all
gathered requirements.
• Use a prioritization matrix to evaluate requirements based on factors like Document • The SRS should be clear, concise, and easily
importance to users and business goals, difficulty of implementation etc. Requirements understood by all stakeholders.
Prioritize • Focus on building a Minimum Viable Product with core functionalities in
Requirements the initial phase.
SOFTWARE DEVELOPMENT LIFE CYCLE : DESIGN STAGE

Here, we define the software's architecture, considering data flow, application structure, and technology
choices. We craft UI with mock-ups and prototypes, prioritizing UX through testing and feedback. We then
choose a database system and design its schema for efficient storage and retrieval. Finally, a design document
captures all technical decisions, ensuring a smooth transition to development.

OUTLINE OF THE DESIGN PHASE

• Involves outlining the overall structure of the software, encompassing

various components and how they interact. • System Flow Design: Outlining the overall flow of
Defining the • Choosing the appropriate programming languages, frameworks, and tools the system, detailing how different components
System needed to build the software is very important.
Architecture interact and functionalities are executed.
System Design
•This focuses on designing the screens and interfaces users will interact with.
•Mock-ups and Prototypes: Creating visual representations of the UI, allowing for
early user feedback and iteration.
User Interface •Usability and Accessibility: Ensuring the UI is easy to use and navigate for all • Developing comprehensive documents that capture all
(UI) Design users, regardless of their abilities. technical decisions and specifications made during the
design phase.
• These documents serve as a reference point for
• Defining the structure of the data the software will store and Design developers during the implementation phase and ensure
manage. Documentation everyone is on the same page.
• Identifying the different types of data
Data Design • Specifying the characteristics of each entity
SOFTWARE DEVELOPMENT LIFE CYCLE : IMPLEMENTATION AND TESTING & INTEGRATION STAGE

Implementation brings the design to life. Code is written, tested piece-by-piece, and then assembled. The whole
system is rigorously evaluated, including real users, to ensure a smooth user experience before deployment.

OUTLINE OF THE IMPLEMENTATION AND TESTING & INTEGRATION PHASE

• Coding: Developers translate the design documents into functional code • Preparing for Release: Once testing is complete
using the chosen programming languages and frameworks. and any bugs are fixed, the software is prepared
• It involves : Writing maintainable code, implementing functionalities as per for deployment to the target environment.
Development design specifications.
• Choosing a deployment method (e.g., on-premise
Deployment servers, cloud platforms).

• Component Integration: Individual software

components developed by different programmers are
Integration assembled and integrated to form a cohesive system.
• User Manuals and Training
Materials: Creating user manuals and
training materials to help users understand
• Comprehensive Testing: Rigorous testing is essential to ensure Documentation and effectively utilize the software.
the software functions as intended and meets all user
Testing requirements.
SOFTWARE DEVELOPMENT LIFE CYCLE : MAINTENANCE STAGE

Maintenance keeps the software healthy! Bugs are squashed, security patches are applied, and performance is
monitored to keep things running smoothly. New features can be added to stay competitive, and user support
ensures happy users. Regular reviews keep the software relevant and secure in the ever-evolving tech world.

OUTLINE OF THE MAINTENANCE PHASE

• Providing Assistance: Offering ongoing user
• Addressing Issues: As users interact with the software, bugs and errors may support through various channels
be identified. The maintenance phase focuses on promptly resolving these (e.g., FAQs, knowledge base, help desk) is
Bug Fixes and issues through bug fixes and updates. crucial. This empowers users to resolve issues
Updates
User Support independently and ensures a positive user
experience.
• Optimizing Performance: Regularly monitoring the software's
performance is essential. This involves identifying and
Performance addressing bottlenecks that may slow down user experience. • Maintaining Stability: As new features and
Monitoring
updates are introduced, maintaining clear
version control is essential. This ensures
• Evolving Needs: User needs and market trends may evolve over previous versions remain stable and functional
time. The maintenance phase allows for the development and Version Control for users who may not be ready to upgrade.
New Feature implementation of new features to enhance the software's
Development: functionality and keep it competitive.
TYPES OF SOFTWARE DEVELOPMENT LIFE CYCLES

Agile Model: This iterative and incremental model emphasizes

Waterfall Model: This traditional, sequential model
flexibility and continuous feedback. The project is broken down
follows a rigid, step-by-step approach. Requirements
into smaller chunks (sprints), with requirements and
are defined upfront, and each phase
functionalities evolving throughout the development process. It's
(planning, design, development, testing, deployment,
ideal for projects with evolving requirements or where user
maintenance) is completed in order before moving to
feedback is crucial.
the next. It excels in well-defined projects with clear
requirements, but may struggle to adapt to changing
needs.
Spiral Model: This risk-driven model combines elements of
Waterfall and iterative models. It emphasizes risk identification
and mitigation throughout the development lifecycle. Each
Iterative Model: Similar to Agile, this model focuses on iterative iteration involves risk assessment, followed by
development cycles. However, it has a more defined planning development, testing, and planning for the next iteration.
stage at the beginning of each iteration. It provides a balance
between the structured approach of Waterfall and the adaptability
of Agile.

V-Shaped Model: This model emphasizes a strong verification and Big Bang Model: This high-risk model involves minimal planning
validation process. It mirrors the Waterfall model, with a and jumps straight into development with limited upfront
corresponding testing phase for each development stage. This requirements. It's rarely used for large-scale projects due to its
ensures rigorous quality control throughout the development unpredictable nature, but may be suitable for small, quick
lifecycle. prototypes.
PROS AND CONS OF SOFTWARE DEVELOPMENT LIFE CYCLES
ADVANTAGES DISADVANTAGES

Enhanced Quality: By following a defined process with clear stages and Reduced Flexibility: Some SDLC models, like the Waterfall
deliverables, SDLCs promote the creation of high-quality model, can be rigid and inflexible. They may struggle to adapt to
software. Each phase focuses on specific aspects like requirements changing requirements or unforeseen challenges that arise during
gathering, design, testing, and maintenance, reducing the likelihood of development. This can be problematic for projects with evolving
errors and defects slipping through the cracks. needs or where user feedback plays a crucial role.

Potential for Delays: While SDLCs aim to streamline

Reduced Risks: SDLCs encourage proactive risk identification and
development, some models may introduce additional processes
mitigation throughout the development process. By planning for
and documentation that can lead to delays, especially in the initial
potential challenges early on, the likelihood of project delays, cost
stages. Finding the right balance between thorough planning and
overruns, and unforeseen issues is significantly reduced.
efficient execution is key.

Increased Cost-Efficiency: The structured approach of SDLCs helps

May Not Suit All Projects: Not all projects require the same level
avoid rework and project delays, which can be significant cost
of structure. SDLCs may be overkill for small, simple projects with
drivers. By clearly defining requirements and following a well-
well-defined requirements. Choosing the appropriate model based
defined process, resources are allocated efficiently, leading to cost
on project complexity is crucial.
savings in the long run.

Greater User Satisfaction: SDLCs prioritize user needs throughout

Limited Room for Innovation: While SDLCs promote well-defined
the development process. Requirements gathering, testing
processes, they may inadvertently stifle creativity and
phases, and user feedback loops ensure the final software delivers
innovation. Finding ways to encourage innovation within the
value and meets user expectations. This leads to a more positive
framework of the chosen SDLC model is important.
user experience and increased user satisfaction.