Network attached storage (NAS) devices are useful for more than simply backing up files. Since they contain their own operating system, memory and processor, they can also act as a BitTorrent client, iTunes or DLNA server, or as an online file server.

Configuring a NAS to let you access your music, photos, video and other files from any machine with a web connection, anywhere in the world, isn't always a straightforward task. You need to open the correct ports on your router, which is made more difficult without having a static IP address. Buffalo has tried to simplify this task with the CloudStation Duo, which combines its traditional LinkStation NAS box with a web-based remote access service from PogoPlug.

After creating an account with PogoPlug, pictures, music and films can be streamed directly to a browser or Android/iOS app. The interface isn’t as polished as we'd like, but it works well. Although similar services can also stream movies from a PC to a mobile app, Buffalo lets you bypass a PC by building in this functionality directly to the NAS.

The CloudStation is more compact and less obtrusive than many other NAS devices we've seen. It‘s encased in a matt black plastic housing, and is roughly the size of a thick A5 dictionary. Power and disk activity LEDs are found at the front, while there are gigabit Ethernet and USB 2.0 ports at the rear. A quiet fan helps to keep cool the hard drives inside.

Buffalo's CloudStation Duo is sold with two 1TB disks inside. It uses the older SATA II interface rather than SATA III, although the difference in performance would be noticeable only when using inordinately fast SSDs.

To access the internal disks you must remove the cover and tug the metal catch. No mounting rails or screws are required to fit the disks inside the Buffalo CloudStation Duo.

As we've come to expect from Buffalo hardware, configuration is handled via a vlear and concise software interface. With the exception of a small delay when scanning for USB devices, we found it very responsive, too.

The CloudStation Duo's 1.6GHz Marvell processor is no slouch, and strong performance is assured with 256MB of onboard memory.

Unlike standard two bay NAS drives, Buffalo's CloudStation Duo doesn't support a Raid 0 configuration. Instead, Raid 1 can be used to mirror the drives, or JBOD lets you set them up as individual entities. Although NAS performance can be affected by the network speed and disk controller as much as the disks themselves, we'd like to have the option to use other Raid setups for times when performance is more important than security.

The Buffalo CloudStation Duo was far from the fastest NAS we've seen in our benchmarks. In our usual 15GB file copy test, we saw read speeds of 26MBps, and write speeds of 22MBps. When streaming a full-HD movie we found no problems with stuttering or lag, however.


We'd love to recommend the Buffalo CloudStation Duo, if only its network performance wasn't so lacklustre. Its build quality is superb, and it's handy to be able to stream media without needing to switch on the PC.