Software verification

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Software verification is a discipline of software engineering whose goal is to assure that software fully satisfies all the expected requirements.


Broad scope and classification

A broad definition of verification makes it equivalent to software testing. In that case, there are two fundamental approaches to verification:

Dynamic verification (Test, experimentation)

Dynamic verification is performed during the execution of software, and dynamically checks its behavior; it is commonly known as the Test phase. Verification is a Review Process. Depending on the scope of tests, we can categorize them in three families:

The aim of software dynamic verification is to find the errors introduced by an activity (for example, having a medical software to analyze bio-chemical data); or by the repetitive performance of one or more activities (such as a stress test for a web server, i.e. check if the current product of the activity is as correct as it was at the beginning of the activity).

Static verification (Analysis)

Static verification is the process of checking that software meets requirements by inspecting the code before it runs. For example:

Verification by Analysis - The analysis verification method applies to verification by investigation, mathematical calculations, logical evaluation, and calculations using classical textbook methods or accepted general use computer methods. Analysis includes sampling and correlating measured data and observed test results with calculated expected values to establish conformance with requirements.

Narrow scope

When it is defined more strictly, verification is equivalent only to static testing and it is intended to be applied to artifacts. And, validation (of the whole software product) would be equivalent to dynamic testing and intended to be applied to the running software product (not its artifacts, except requirements). Notice that requirements validation can be performed statically and dynamically (See artifact validation).

Comparison with validation

Software verification is often confused with software validation. The difference between verification and validation:

See also

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