SDLC Traditional Life Cycle Models

System Development Life Cycle (SDLC) Models

• Traditional Life Cycle Models typically use structured approaches in software development and system engineering processes.

• They follow a linear and sequential process, with clearly defined stages.

• Examples include the Waterfall Model, V-Model, Incremental Model, Iterative Model, and Prototype Model.

Learning Objectives

• Students should be able to identify traditional SDLC models.

• They should explain differences between different systems life cycle models.

• They should list all stages of the SDLC.

2.1 Traditional Life Cycle Models

• Waterfall Model: Linear where each phase (Requirements, Design, Implementation, Testing, Deployment, and Maintenance) must be completed before proceeding to the next phase.

• V-Model (Validation and Verification): Extends the Waterfall model by emphasizing testing and verification at each development stage.

• Incremental Model: Divides the project into smaller segments for incremental development and delivery.

• Iterative Model: Focuses on repeated cycles for refining and improving the system at each iteration.

• Prototype Model: Involves an initial prototype to gather user feedback and then refine requirements.

2.1 Traditional Life Cycle Models (Continued)

• Diagrams illustrate the Waterfall model's sequential phases (Requirement Analysis, System Design, Implementation, Testing, Deployment, Maintenance).

• A diagram also demonstrates the V-Model, showing verification and validation phases.

• Diagrams showcase the incremental model, outlining phases of requirement analysis, design & development, testing and implementation.

• Diagrams illustrate iterative model (Requirements, Analysis & Design, Implementation, Planning, Evaluation, Testing, Deployment).

• Diagrams visually describe the steps in the prototype model (Start, Requirement Gathering, Quick Design, Prototype Building, Engineer Product, Refine Prototype, Customer Evaluation and Stop).

2.2 Modern Life Cycle Models

• Modern Life Cycle Models emphasize flexibility, adaptability, and iterative progress catering to dynamic business requirements and evolving technologies.
• These are contrasted with traditional models, emphasizing continuous improvement, collaboration and faster delivery.

2.2 Modern Life Cycle Models (Continued)

• Rapid Application Development (RAD): A modern methodology emphasizing speed, flexibility, and iterative development, minimizing planning and maximizing user involvement to deliver a working product quickly.

• Agile Model: A flexible and iterative approach focusing on collaboration, customer feedback, and small, rapid releases.

• Scrum: A subset of Agile emphasizing short development cycles (sprints) and well-defined roles (Scrum Master, Product Owner).

• Kanban: A lean methodology emphasizing visual workflows and limiting work-in-progress to enhance efficiency.

• DevOps: Combines development and operations to enhance collaboration, automate processes and enabling continuous delivery and integration..

• Spiral Model: Combines iterative development with a risk-driven approach, repeatedly passing through planning, design, build, and testing phases.

2.3 Overview SDLC Stages

• The Traditional methodology used to develop, maintain, and replace information systems.

• This methodology consists of five phases: Planning and Selection, Analysis, Design, Implementation, and Maintenance.

• Phases aren’t necessarily sequential.

• Each phase has a specific outcome and deliverable.

• Individual companies often customize the life cycle process.

2.3 Overview SDLC Stages (Continued)

• Planning: The first phase of the SDLC where an organization identifies, analyzes, prioritizes, and arranges its information system needs.

• Analysis: Studying current procedures and information systems to determine requirements; generate alternative designs; compare alternatives and recommend best alternative options.

2.3 Overview SDLC Stages (Continued)

• Design: Describes the recommended solution in logical and physical system specifications (Logical design – functions independently of the platform; Physical design – technology specific details).

• Implementation: Coded, tested, installed and supported information system.

2.3 Overview SDLC Stages (Continued)

• Maintenance: Addresses the maintenance phase of the SDLC; programmers make changes to the system based on user requests, to reflect evolving business conditions ensuring the system remains functional and useful.

• Various deliverables and products associated with each SDLC phase are listed in a table.