High Quality Content by WIKIPEDIA articles! RACF, short for Resource Access Control Facility, is an IBM software product. It is a security system that provides access control and auditing functionality for the z/OS and z/VM operating systems. Its primary market competitors have been ACF2 and TopSecret, both now produced by CA, Inc.In addition to being one of the most mature and scalable security monitors in computing, it has some interesting features that are not often found in Microsoft Windows or Unix environments. It can, for example, set permissions for file patterns - that is, set the permissions even for files that do not yet exist. Those permissions are then used for the file (or other object) created at a later time. In other words, RACF establishes security policies rather than just permission records.