Abstract: A security platform, for stand-alone or networked processors using UNIX or similar operating systems, limits access to system resources, including software and hardware, by personnel using the system and by other resources within the system. The platform implements a rules-based naming and rule convention for types of access of security interest to one or more served application programs, providing rule sets each of which associate an access type with a subject and, optionally, one or more objects to which are compared access demands made by the served application to the platform in the same form as the rule sets to determine whether the access demanded is permissible. Internal platform security is provided by limiting users who can modify the platform and its resident rules.