SDLC Traditional Models Overview

System Development Life Cycle (SDLC) Models

• The term "Traditional Life Cycle Models" refers to structured approaches in software development and system engineering for planning, designing, implementing, testing, and maintaining projects in an organized way.
• These models are called "traditional" because they follow a linear or sequential process, usually with clearly defined stages.

Learning Objectives

• Identify traditional SDLC models
• Explain differences between systems life cycle models used in system development
• List all stages of the SDLC

Traditional Life Cycle Models (Examples)

• Waterfall Model: A linear approach where each phase (Requirements, Design, Implementation, Testing, Deployment, and Maintenance) is completed before proceeding to the next.
• V-Model (Validation and Verification): Extends the Waterfall model by emphasizing testing and verification at each development stage.
• Incremental Model: Divides a project into smaller segments for incremental development and delivery.
• Iterative Model: Repeatedly refines and revisits processes through cycles to enhance the system at each iteration.
• Prototype Model: Involves creating an initial prototype to gather user feedback and refine requirements.

Traditional Life Cycle Models (Diagram Examples)

• Diagrams illustrate the different stages of the Waterfall, V-Model, Incremental, Iterative and Prototype Models

Modern Life Cycle Models (Examples)

• Rapid Application Development (RAD): Emphasizes speed, flexibility, and iterative development, facilitating quick delivery of a working product with minimal planning and maximal user involvement.
• Agile Model: A flexible and iterative approach that highlights collaboration, customer feedback, and rapid releases in small increments.
• Scrum: A subset of Agile with short development cycles (sprints) and defined roles like Scrum Master and Product Owner.
• Kanban: A lean methodology focusing on visual workflows and limiting work-in-progress for enhanced efficiency.
• DevOps: Combines development and operations to optimize collaboration, automate processes, and enable continuous delivery and integration.
• Spiral Model: Combines iterative development with a risk-driven approach, recursively passing through phases of planning, design, build, and testing.

Overview of SDLC Stages

• Planning: The initial SDLC phase where organizational information system needs are identified, analyzed, prioritized, and organized.
• Analysis: Involves studying current procedures and systems, determining requirements, generating alternative designs, comparing alternatives, and recommending the best alternative.
• Design: Consists of converting the recommended solution into logical and physical specifications for the system's functional features, independent of any computer platform.
• Implementation: The phase where the information system is coded, tested, installed, and supported within the organization.
• Maintenance: The final phase during which an information system is repaired and improved. Programmers make adjustments based on user requests and evolving business conditions to maintain system functionality.

Products, Outputs or Deliverables of Each SDLC Phase

• A table outlines the products, outputs and deliverables for each phase of the SDLC. This includes priorities for systems and projects; system scope and high-level system specifications, assignment of team members, and resources.  Further details included about features, justification for systems, and alternative systems specifications. Additional details on implementation, maintenance, code, training, documentation etc are included.