Computer Science – 12.1 Program Development Life cycle | e-Consult

Both the V-model and the Waterfall model are sequential software development life cycles. However, the V-model emphasizes verification and validation at each stage, while the Waterfall model focuses primarily on completing each phase before moving to the next.

Waterfall Model: As previously discussed, the Waterfall model is a linear, sequential approach. Each phase must be completed before the next begins. Testing is typically performed at the end of the development process.

V-Model: The V-model extends the Waterfall model by explicitly linking each development phase with a corresponding testing phase. For example, requirements are linked to acceptance testing, design is linked to integration testing, and code is linked to unit testing. This ensures that testing is planned and executed in parallel with development, leading to earlier detection of defects.

Comparison:

• Emphasis on Testing: V-model has a stronger emphasis on testing throughout the development lifecycle.
• Early Defect Detection: V-model facilitates earlier detection of defects by linking development phases to specific testing phases.
• Documentation: Both models require extensive documentation.
• Flexibility: Waterfall is less flexible than the V-model.

When is the V-model more suitable than the Waterfall model? The V-model is a more suitable choice than the Waterfall model when:

• Requirements are well-defined and stable: The V-model works best when the requirements are clear and unlikely to change.
• High reliability is critical: The V-model's emphasis on testing ensures that the software is thoroughly tested and reliable.
• Regulatory compliance is required: The V-model's documentation and traceability are beneficial for meeting regulatory requirements.
• Project is relatively small and simple: The overhead of the V-model is justified for smaller projects where the benefits of early defect detection outweigh the additional effort.