With protected subsystems, you have
a mechanism to provide conditional access to data that is not available
with traditional OpenVMS access controls. Traditionally, you give
users privileges to bypass protection codes or access control lists
(ACLs). In giving these privileges, however, you grant users a wide class
of access. (Refer to Appendix A “Assigning Privileges” for
information on the power different privileges carry.) Protected subsystems
avoid extensive privilege use by individual users.