Software of unknown pedigree

SOUP stands for Software of Unknown (or Uncertain) Pedigree, and is a term often used in the milieu of safety-critical and safety-involved systems. Often, engineering projects are faced with economic or other pressure to embody into their high integrity systems software that has not been developed to known standards, software which has unknown or no safety-related properties. This is known as SOUP. Similar, less commonly used, terms apply to firmware 'FOUP' and hardware 'HOUP'.

The Problem

The problem with SOUP is that a) it cannot be relied upon to perform safety-related functions, and b) it may prevent other software, hardware or firmware from performing their safety-related functions. The SOUP problem is therefore one of insulating the safety-involved parts of a system from the SOUP and its undesirable effects.