In computers, functionality assurance is a form of continuous testing to assure a working system remains functional.
From a technology risk point of view, there are a number of long-term risks (difficult to envisage) that might result in unacceptable application functionality status. The functionality assurance model asserts that it is not acceptable to detect reduced functionality through user interaction and is cost beneficial both from a functionality and a risk management point of view to assure that the applications within scope operate at full functionality. There are many states that can produce reduced functionality, such as security updates to operating systems, internal system errors, changes to the external application context and even application updates. Functionality assurance is not performed with automated vulnerability scanning as such scans cannot detect introduced or undetected vulnerabilities.
