Full testing of all aspects of a specification requirement. For example, testing every possible value for an argument to a function. Testing sufficientto validate that the implementation under test matches a specification requirement without exhaustive testing. For example, a subset of the possible values of an argument to a function, exercising boundary and representative conditions. For example, that a function exists without validating its processing of any arguments.
Testing occurs at the exhaustive level where practical.
However in many areas it may not be practical to do so due to the time and system resources required. Identification testing is rarely used unless the specification requires it, by stating merely that a feature exists and defining no behaviours or values. Once the test suite specification has been developed it needs validating to assure that its a correct representation of the requirements of the specification under test. The Open Group has developed methods for managing review feedback which allow development to proceed in an objective and timely fashion. This is achieved using review guidelines and a pro-forma responses.