Red Hat Enterprise Linux 5 Administration Security Desktop, examines topics in system administration, security, file and device management, and desktop use, including the Red Hat Enterprise Linux system-config administration tools. System administration covers software installation and update with Yum, user management, start up and service management, virtualization, system monitoring, and shell configuration. Security includes authentication, public and private key encryption (GPG ), SE Linux, firewalls  using IPtables, the Secure SHell (SSH), and Kerberos. Device and file system management topics cover udev, the Hardware Abstraction Layer (HAL), Logical Volume Manager (LVM), Linux software RAID, and backups. Desktop covers desktop preferences, GNOME, KDE, desktop applications, shared folders, shell commands, network connections, and printers.