QNAP System's TS-409 Pro is a business-focused, four-bay network-attached storage (NAS) device with Gigabit Ethernet. The device supports RAID 0/1/5/6 as well as JBOD and linear drive array standards, and has a bevy of server and security configuration options.

The TS-409 Pro is almost attractive for a NAS device. It has a black and silver fascia, and a hinged door with a perforated grill faceplate to provide easy access to the hard drives and allow good airflow. A bevy of LEDs at the bottom of the unit provide information on the TS-409 Pro's server, drives and operational health. The drives are hot-swappable, although this isn't as easy as with D-Link's DNS-343. Drives must first be screwed into drive carry trays, which are then screwed into the chassis. This provides a secure connection, but it increases the amount of time it takes to swap drives.

The device has three USB ports for connection to printers, external hard drives, USB drives or a USB UPS. Users can automatically back up data from external hard drives and USB drives to the TS-409 Pro's internal drives thanks to an auto-copy button on the device.

Initial setup is fairly easy. Step-by-step configuration can be initiated using either the provided software or the device's embedded Web server. Format times are dependent on drive size and array configuration; we found the initial format to be fairly quick when using a 1TB drive.

The embedded Web server provides access to the device's settings. Although it isn't as simple as the one found in the DNS-343, it provides all the necessary information and options for both the technologically adept and novices. The device's media and file server capabilities are quite impressive. The TS-409 Pro can be configured for a number of servers, including iTunes, remote FTP, UPnP, MySQL, Web and a multimedia server with a dedicated folder for easy access and storage. The device's 'Download Station' allows automated downloading. Unlike D-Link's DNS-343, the TS-409 Pro supports BitTorrent downloading as well as standard FTP and HTTP downloads. Unfortunately, there's no way to schedule (or throttle) downloads. The TS-409 Pro offers a number of RAID options. RAID expansion and migration can both be accomplished online, allowing users to add new drives and alter the RAID configuration without having to reboot or turn off the server.

We are slightly perplexed as to why the unit offers a RAID-6 configuration option. Although RAID-5 configurations are common in four-bay NAS devices, this is the first time we've come across a RAID-6 option for one. The relatively new RAID standard, which allows for up to two drive failures in an array, seems slightly redundant for four-drive device. The standard is designed for use in arrays consisting of more than 12 drives, so its use in this device would only be justified in cases of high data importance.