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The Terabyte Zone

A review of an external drive that can hold one trillion bytes of data – and how it might change the way we deal with our personal information.

A terabyte for less than a grand! Now, that’s progress.

Maxtor’s new OneTouch III external drive connects to a PC, Macintosh, or Linux computer and holds a trillion bytes of data (actually a bit less than a true terabyte, which is 1,0244 or 1,099,511,627,776 bytes). This device is fast and silent and can be comfortably carried in a backpack or a thick briefcase. Open up the box and you’ll actually find two 500-gigabyte hard drives: the OneTouch III uses a technology called RAID (redundant array of independent disks) to combine the drives into a single high-capacity virtual device.

I have been using external hard drives for large-scale data storage for more than a decade. Of course, the definition of “large-scale” has changed considerably over that time. I bought my first external hard drive back in 1993; it cost $995 and stored one gigabyte. In the intervening years, engineers have improved magnetic storage technology even faster than they’ve increased computers’ processing power. In 1993, my desktop workstation ran at a clock speed of 33 megahertz and had 32 megabytes of RAM; my desktop computer today runs at 100 times that speed and has 32 times as much RAM. But the Maxtor holds a thousand times as much data as my first external drive.

Over the years, I’ve bought drives from literally a dozen manufacturers. But I’ve never found one as good as the Maxtor OneTouch III – and not just because of its mammoth capacity, which puts it among the largest hard drives on the consumer market. The device is virtually noiseless in operation and cool to the touch, both important features in today’s home offices. Unlike most other drives, the OneTouch III has three different interfaces on the back – USB 2.0, Firewire 400, and Firewire 800. That means it will work with practically every desktop and laptop on the market today; if your computer doesn’t have one of these interfaces, you can buy a card for less than $30. The connector is a sturdy barrel that’s unlikely to break – no delicate pins here.

All this engineering makes the OneTouch III a pleasure to use. But why would anyone actually need a terabyte of storage in a home or small office? And will someone who has it actually know what to do with it?

Back when I bought my gigabyte drive in 1993, it wasn’t very hard to put all that storage to use. CD-ROMs, which were just beginning to become widespread, stored 600 megabytes each. Copying a single CD-ROM to the hard drive could nearly fill it up. It’s a bit harder to generate a terabyte of data, and the average consumer doesn’t need quite that much storage – yet. But in a few years, a terabyte for a household will seem pathetically small. The reason, of course, is digital video.

Music and still photography have been driving the need for consumer storage in recent years. Even with compression technologies like MP3 and JPEG, songs and high-resolution still photographs still require between one and five megabytes each. Collect your photos of the family trips, throw in a few birthday parties, and add the music collection of just one teenager, and pretty soon you need tens of gigabytes, if not a few hundred, to keep it all at hand.

But digital video is a different animal entirely. MiniDV video cameras record digital video on tape at 250 megabytes per minute, or 15 gigabytes per hour. Many new digital video cameras have flash RAM or miniature hard drives that can capture several gigabytes of compressed video per shooting. And these days, most digital cameras will create video clips – files that can quickly grow to hundreds of megabytes in length. Just a few vacation videos will stuff the hard drive that came with your PC. (The largest hard drives for off-the-shelf desktop or laptop computers these days hold only about 500 gigabytes.) So as digital recording technologies become more commonplace, consumers will face a very real dilemma: either purchase terabytes of extra storage or discard their digital memory chests. I suspect many will opt for the storage.

Although there are other ways to capture and archive digital information, none offers the permanence, reliability, and convenience of hard drives. It’s certainly cheaper to keep your video on miniDV tape, which costs about $4 for each recorded hour, but it’s much more convenient to have all your videos on a single drive than to have them scattered across two or three shelves. Hard drives don’t degrade as fast as tapes do, and unlike tape drives, they don’t need to be cleaned to maintain picture fidelity.

What’s more, as download services like iTunes, YouTube, the Google Video store, and Movielink become more popular, consumers will be storing not just the songs they’ve purchased online but also TV shows and movies. Some computers even act as digital video recorders, copying data directly from a cable or satellite feed – which will further fuel the need for storage. Devices like the Maxtor OneTouch III will fill that need.

Combining two 500-gigabyte drives is more than just a gimmick to let Maxtor
say it sells a terabyte hard drive. Having two drives is actually a blessing. It makes the system either faster or more reliable than a similarly equipped single drive could possibly be.

Unfortunately, you need to choose between speed and reliability: you can’t have them both. Under the default RAID configuration, called “drive striping,” the OneTouch III alternates between drives as it records data files, writing the first segment to drive one, the second to drive two, the third to drive one, and so on. Because the device has two disk controllers and two sets of cache memory, it writes data roughly twice as fast as a single drive. But drive striping is risky: if either drive fails, all the data on both drives may be lost. A second RAID configuration is called “drive mirroring.” In this mode, every block of data is stored on both drives. Mirroring reduces the capacity of the OneTouch III from a terabyte to 500 gigabytes, but it dramatically improves reliability: both drives have to fail at precisely the same time for you to lose data.

RAID technology and terabyte-sized storage systems were invented in the 1980s for supercomputers and moved to the world of corporate computing in the late 1990s. In that era, considerable skill was required to assemble and manage this much storage. And unfortunately, while storage technology has gotten a lot smaller and cheaper, the tools for managing all that stored data have not gotten much simpler. All of us are going to be spending more of our time trying to manage our storage devices effectively (as the choice between drive striping and drive mirroring illustrates), but there aren’t yet many easy-to-use tools for organizing a terabyte of digital video.

Of course, there’s always Windows Explorer or the Macintosh Finder: you can create a directory for each year and store your videos in chronological order. You can then use the Windows search utility, or Spotlight on a Mac, to search your collection by file name. But what I would really like is some kind of semantic video search engine that indexes video by analyzing the dialogue or the scenes, taking into account the time of year, the location, and the people in the picture. Then I could simply say, “Computer, find all video clips of my mother in a red dress.” Unfortunately, that kind of search technology is still in the research stages.

The Maxtor drive does make one storage task easier: backing up other hard drives. The word “OneTouch” refers to a prominently placed push button on the front of the device; pressing that button causes your host computer to run Retrospect Express, the personal backup program included with the drive.

But I don’t use Retrospect Express. When I back up my laptop, I just copy all the files into a new directory. This is less efficient, but it’s a lot faster to recover the backed-up files using the Macintosh Finder or Windows Explorer than using Retrospect’s “Restore” facility.

Of course, having a terabyte of backup capacity could change our notions about what it means to back up a computer in the first place. Instead of storing a snapshot of all the files on the computer at a particular point in time, the way automatic backups do, we could continuously store every version of every file that we’ve ever edited. Your browser’s “history” could be a real history, with a copy of every Web page you ever viewed, every song or video clip you ever downloaded. Storage on this scale would mean never having to hit “delete.” These kinds of desktop backup systems are also a current subject of research.

With great storage comes a great need for storage management. Today’s terabyte drives deliver the bytes – but unfortunately, it’s still up to the user to know what to do with them.

Simson Garfinkel researches computer forensics at the Harvard Center for Research on Computation and Society.

OneTouch III Turbo Edition Hard Drive Maxtor
$900 list, $700 street

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