SDLC Phases

System Development Life Cycle (SDLC)

The SDLC is a structured framework that defines the phases involved in building an information system from initial concept to deployment and beyond. Each phase produces specific deliverables that feed into the next phase.

Overview of SDLC Phases

   Planning
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   Analysis
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   Design
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   Implementation
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      v
   Testing
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   Deployment
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   Maintenance

Phase 1: Planning

The planning phase establishes the project scope, objectives, and feasibility. Key activities include:

• Defining the problem or opportunity
• Conducting a feasibility study (technical, economic, operational)
• Estimating costs and timelines
• Developing a project plan
• Identifying stakeholders and forming the project team

Phase 2: Analysis

The analysis phase determines what the system must do. Key activities include:

• Gathering and documenting requirements
• Analyzing current workflows and processes
• Creating DFDs, ERDs, and use case diagrams
• Building a data dictionary
• Defining acceptance criteria

Phase 3: Design

The design phase determines how the system will work. Key activities include:

• Designing system architecture
• Creating input/output specifications
• Designing the database schema
• Designing user interfaces
• Creating system flowcharts and program specifications

Phase 4: Implementation

The implementation phase builds the system. Key activities include:

• Writing and compiling code
• Unit testing individual modules
• Integrating modules
• Conducting system testing
• Preparing user documentation and training materials

Phase 5: Testing

While testing occurs throughout the SDLC, dedicated testing activities include:

• Unit Testing: Testing individual components
• Integration Testing: Testing combined modules
• System Testing: Testing the complete system end-to-end
• Acceptance Testing: Users validate the system meets requirements

Phase 6: Deployment

The system is delivered to users. Key activities include:

• Choosing a changeover strategy (parallel, pilot, phased, direct)
• Training end users
• Migrating data from the old system
• Going live and monitoring for issues

Phase 7: Maintenance

After deployment, the system requires ongoing support. Types of maintenance include:

• Corrective: Fixing defects
• Adaptive: Adjusting to environmental changes
• Perfective: Enhancing performance or features
• Preventive: Avoiding future problems

Summary

The SDLC provides a roadmap for system development. Understanding each phase and its deliverables ensures that projects are well-organized, risks are managed, and the final system meets user needs.