Network Service
These options allow you to enable various network services, including Samba/CIFS, AFP (Apple Network Setup), NFS, FTP, TFTP, WebService, UPnP, Bonjour, SSH, DDNS, and WebDAV.
Application Server
ThecusOS includes an iTunes server application, which allows you to play multimedia files stored on the NAS over your iTunes client.
Put a tick into the "show in login" box to make the application available on the login page.
This tab will display most system modules available on Thecus' official website. If you don't have an Internet connection, which would be pretty strange given you have a NAS, you can use the modules.zip file on the installation CD instead. This zip file includes most popular official NAS modules. You should, however, check the Thecus website for the most recent version of a module.
Backup
ThecusOS supports various backup types. DOM backup saves the system's configuration at specified intervals while Rsync Target Server allows you to back your data to a remote server.
Data Burn allows you to write files and folders to an optical disc, write an image to a disc, or write files and folders to an image. You must install a USB-burning device to use this feature with the NAS.
You can back your data to a remote network location or a NAS, a local location, or Amazon S3.
External Devices
External Devices Options only includes options for UPS and USB printers, which is pretty weird. We hope Thecus will provide more options sometime in the near future. As we noted in a previous Thecus NAS review, they should at least add an option that allows you to format external disks since you currently have to format external drives on a PC before hooking them up to the NAS. That said, the first tab in the group refers to attached printers while the second allows you to configure a few relevant setting, or enable or disable UPS monitoring.
If you connect an external storage device, it will be displaced in the Disk Information tab. You won't have any control over any of the external devices displayed here, but will be able to eject them.