V-Model (Software Development): A Comprehensive Handbook

Verification Phases

The verification is typically on the left side of the V-shaped model. It involves product development stages and the process evaluation to ensure the requirements are met. This phase often is static analysis and aims to answer the question of “Does the delivered product meet the requirements and specifications?”

The verification phase can be broken down into five smaller stages:

Business Requirement Analysis

Before the actual work starts, the team needs to understand the customer requirements thoroughly. Most customers have a vague idea of what they want, so proper communication to understand their needs and expectations is paramount.

After a thorough conversation with the customers, the gathered information needs to be refined and rewritten into clear, consistent, and unambiguous requirements and put in the user requirements document. This document should spell out all the functional and non-functional requirements as well as any priorities that the team needs to pay special attention to.

System Analysis

The next step is to interpret the user’s requirements. System engineers and the development teams discuss the requirements and convert them into product features. The system design step typically involves hardware requirements, needed resources, and any additional communication to set up the product development.

Software Architecture Design

Software architecture is chosen based on a number of criteria: the list of modules, their brief functionality, interface relationships, dependencies, relationships, database tables, technological details, and the list goes on.

This overall high-level design enables the design and documentation of integration tests.

Module Design

While software architecture is a high-level design, the module design is considered a low level design. To be specific, a detailed internal design of the modules is developed. Factors like its compatibility with external systems, how the data is collected and integrated, and so on are all carefully considered in this phase. Based on all this information, unit tests may be developed simultaneously.

Coding

The detailed module designs are taken up in the coding phase. Based on the designs of the previous steps, the development team selects the most suitable programming language. A coding standard and principle must be followed at this stage. The codes go through careful review and checking before being checked into the repository.

Validation Phases

The validation phase is on the right side of the V shape. While the verification phase makes sure the requirements are met, validation phases use dynamic analysis techniques, meaning it involves both functional and non-functional testing to guarantee that the product meets customer requirements and expectations. The validation phase can be broken down into four smaller tests.

Unit Testing

In the V model, unit testing corresponds to the module design phase. Also referred to as component test execution, this type of test is run to identify any bugs or errors at the unit level. The test is conducted on the smallest entities, like modules, objects, or classes. These elements are tested in isolation from the system to make sure they work properly. Defects are typically fixed as soon as they are detected.

Integration Testing

Corresponding to the system analysis stage, integration testing is performed to certify the communication between the modules. To be specific, teams review how modules are integrated and how the data is passed through interfaces. Integration testing aims to check and see if the independently tested groups can coexist and communicate with one another.

System Testing

System testing happens during the system design stage. This test is done by the client’s business team. The main aim of this stage is to go through the entire system, as well as functional and non-functional test cases, to make sure every business requirement is met.

Acceptance Testing

This is related to the business requirement analysis part of the V-model. It is performed in the user environment and verifies if the product has any compatibility issues with different systems. This test is used to test non-functional problems like load time or performance. In short, acceptance testing is used to see if the product is ready for the real world.