Model Based System Engineering

Chapter 5Model Verification and Validation

5.1 Verification

The verb “to verify” comes from the Low Latin “verificare,” meaning “to present as true” (verus: true, facere: to do). Its meaning then evolved into “to examine the truthfulness of a thing.” Today, system-level verification consists of determining the correctness and veracity of what is expressed in the system by both sides, taking into account differences in viewpoints and expectations.

In model-based systems engineering (MBSE), verification is important for checking the quality and accuracy of system models. Verification determines whether a model correctly represents the intended design and complies with established rules on syntax, semantics, and consistency (Engel 2010).

Verification confirms that the model is built correctly according to its specifications and that there are no internal errors or inconsistencies. It answers the question: “Are we building the product correctly?”

• It takes place throughout the development process.
• It verifies that the deliverables of a phase meet the conditions established at the start of that phase.
• It uses techniques such as reviews, inspections, audits, walk-throughs, and testing (unit tests, integration tests, etc.).

By verifying models early in the development lifecycle, potential issues and defects can be identified and fixed before they propagate to later stages, where the cost of correction is significantly higher (Stecklein et al. 2004). Model verification techniques ...