1. Tests to determine whether an implemented system fulfills its requirements.
2. The checking of data for correctness or for compliance with applicable standards, rules, and conventions.
3. [The] process of applying specialized security test and evaluation procedures, tools, and equipment needed to establish acceptance for joint usage of an AIS by one or more departments or agencies and their contractors.
Note: This action will include, as necessary, final development, evaluation, and testing, preparatory to acceptance by senior security test and evaluation staff specialists.
4. In universal personal telecommunications, the process of verifying that a user or terminal is authorized to access UPT services.
Source: from Federal Standard 1037C and from MIL-STD-188 and from the National Information Systems Security Glossary