In order to test the functionality of the WD My Book World Edition, we placed it on our Gigabit-Ethernet network and accessed it from a variety of Windows and Mac desktops and laptops. We connected to it via both wired and wireless connections, as well as remotely over the Internet.
To test the device's performance, we conducted a number of data-transfer tests to and from the device over our network using an HP Pavilion Elite m9550f desktop (2.5GHz Intel Core 2 Quad Q9300, 8GB PC2-6400 DDR2 SDRAM, 1TB NTFS 7200RPM SATA hard drive, ATI Radeon HD 4850 512MB, Windows Vista Home Premium SP1 64-bit) via a Gigabit-Ethernet connection. We conducted large-file write and read tests where we copied a 1.7GB ISO file between the WD My Book World Edition and the HP Pavilion Elite m9550f. We also conducted small-files write and read tests where we copied a 267MB folder made up of 70 JPGs ranging in size from 2.27MB to 4.38MB between the WD My Book World Edition and the HP Pavilion Elite m9550f. We conducted these tests by dragging-and-dropping the folders and files in Windows. We disabled the WD Anywhere Backup tool so that there wouldn't be any background data transfers occurring during testing.
We compared the performance of the WD My Work World Edition against that of a number of NAS devices we've looked at recently, including the Maxtor Central Axis Business Edition, Linksys by Cisco Media Hub, and the Addonics NAS Adapter. We also repeated all of our tests on an older 500GB Maxtor Shared Storage NAS device--copying files between the Maxtor Shared Storage device and the HP Pavilion Elite m9550f. Additionally, we ran our tests on an external hard drive connected directly to a USB 2.0 port on the HP Pavilion Elite m9550f; the drive we used was a 320GB Western Digital Caviar Blue drive (7200RPM SATA-II, 16MB cache) placed into an external enclosure and formatted using the NTFS file system.
The WD My Book World Edition took 107.1 seconds to write and 60.2 seconds to read a 1.70GB ISO file. These speedy transfer rates, hands-down, make the WD My Book World Edition the fastest NAS device we have looked at recently, when it comes to large-size file transfers--and by a sizeable margin. Its transfer rates can't compare to that of a directly-connected USB hard drive, of course; but we wouldn't expect network transfer performance to be as fast as that of a directly-connected drive. The large-file transfer rates on our tests equate to about 16.3MB/Sec (136.4Mb/Sec) for writing and 28.9MB/Sec (242.5Mb/Sec) for reading.
The WD My Book World Edition took 28.5 seconds to write and 17.0 seconds to read a 267MB folder of small files. The device's small-file transfer speeds are also very good, but not necessarily fast enough to make the WD My Book World Edition the undisputed performance leader. We saw similar write performance from the Maxtor Central Axis Business Edition; and the Linksys by Cisco Media Hub was even a few seconds faster. The WD My Book World Edition, however, did have the quickest small-files read performance. On our tests, the WD My Book World Edition writes small files at about 9.4MB/Sec (78.6Mb/Sec) and reads small files at around 15.7MB/Sec (131.8Mb/Sec). The USB-connected hard drive, obviously, bested all of the NAS devices. In fact, we couldn't even generate useful numbers for the USB drive's small-files read performance as Windows cached the files in memory and essentially performed instantaneous transfers whenever we repeated the file copy. (All tests were run multiple times to ensure repeatability.)
As to more anecdotal performance observations, we found the WD My Book World Edition to be very quick to respond to file queries and copies. The only time we noticed any significant lag time was when the device had gone into Sleep mode and our query only then caused the device to wake up.
We also connected the WD My Book World Edition to a power meter to get a sense of how much power it consumes. When the device is sitting idle, it uses only about 7 watts of power. Under load, its power consumption goes up few more watts to about 10 watts. When in Sleep mode, the device sips only about 4 watts of power.