What is the V-Model?

The V-Model is a testing-focused SDLC model where:

• left side: specification and design
• right side: corresponding test levels

The idea: write tests early based on specifications.

Diagram: The V-Model

  graph TD
A[Business Requirements] --> B[System Requirements]
B --> C[High-Level Design]
C --> D[Low-Level Design]
D --> E[Implementation]

E --> F[Unit Testing]
F --> G[Integration Testing]
G --> H[System Testing]
H --> I[Acceptance Testing]

A --- I
B --- H
C --- G
D --- F

Benefits

• clear mapping of tests to requirements
• encourages early test planning

Drawbacks

• can be rigid for fast-moving products
• less natural for rapid iteration than agile approaches

Where it’s used

• regulated industries
• high-risk systems (medical, automotive)