The security of directory services is based in large part on the security of the underlying operating system, and especially on the security of its file system. Directory services can be installed and operated on many operating systems, and this may result in a wide variety of security settings that need to be configured. This variety requires increased planning and corresponding knowledge of the operating system in question. If the resulting overall solution is very heterogeneous or complex, insufficiently planned use of the directory service may cause vulnerabilities during actual operations. Role-based administration of a directory database is also common in connection with directory services. Individual administrative tasks can also be delegated, which leads to the risk of insecure or inadequate system administration if these tasks are not properly planned.