Abstract
Role Based Access Control (RBAC) has gathered much attention in the recent literature. Much of the discussion has focused on theoretical issues, potential features, or on Web or security database implementations. The paper describes an implementation of RBAC mechanisms on LOCK6, a secure operating system developed at Secure Computing Corporation. The implementation has the RBAC features necessary to solve the usual problems in our application domain (that of firewall construction) while providing a path to many of the more advanced RBAC features needed by other application domains. Finally we argue that RBAC alone is not a sufficient mechanism to produce secure systems but that an additional lower level mechanism such as type enforcement is required.