Hard drives hit the road

Here's a surprise: Removable hard drive enclosures could well become the next hot storage technology for PCs, workstations, set-tops and game stations.This might seem unimaginable, but think about it. Floppy drives, CD rewritables, DVD rewritables, tape drive systems and cartridge systems simply can't compare in capacity, performance or price per megabyte to the good old hard drive already installed in your computer.In the last two decades, the density of the hard drive has increased 10,000-fold, and the price per megabyte has decreased 1,000 times, according to Steven L. Kaczeus of DataZone Corp. of Felton, Calif., a manufacturer of ruggedized transportable storage devices.A 60G hard drive will hold about four and one-half hours of uncompressed digital video. A 120G drive can hold about as much music as 192 CDs. Despite these clear advantages, most buyers still think CD or DVD storage peripherals are the way to go.A general reluctance to include hard drive technology as part of our removable storage arsenals is due in part to the well-known fragility of the drives themselves, Kaczeus said. Statistics show that shock and physical abuse of computers, particularly notebook PCs, damages sensitive hard drives and causes 44 percent of all data loss among notebook users.Meanwhile, rapid consumer acceptance of optical CD and DVD drives has put hard drive secondary storage systems in the back of the pack.But companies such as DataZone are looking to catch up. The company's DataBook is an external, ruggedized hard drive weighing only 12 ounces that connects to PC or Mac desktop and notebook PCs.DataBook is designed for a variety of applications such as downloading Internet and MP3 files, system backup, file transportation, fast-and-simple storage capacity upgrades and data archiving. It's available in 10G, 20G and 30G capacities.Other hard drive manufacturers and start-ups are also developing external and internal removable drive products.[IMGCAP(2)] Exactly what are removable hard drives, anyway? According to SimpleTech Inc., a manufacturer of peripherals in Santa Ana, Calif., removable hard drives have all the necessary hardware'including caddies and connectors'to make them the equivalent of a computer's original drive. They should plug right in with no extra hardware.But here is where it gets swampy for potential buyers. Different manufacturers use different names for the various components of removable hard drives. And there are at least two different types to reckon with: removable drive drawers and external drive enclosures.Removable drive drawers, also known as mobile racks and a handful of other names, are designed to give easy access and portability to hard drives. In effect, they provide an interesting compromise between internal and external hard drives.They generally come in two pieces: one piece, the bay, is mounted in a standard 5.25-inch opening in the front of a desktop or tower computer. The other piece, the caddy, contains the hard drive. When the caddy is seated in the bay and locked into place, the connection between the hard drive and the computer's IDE or SCSI port is completed, and the hard drive works normally.This system allows you to easily swap out hard drives without the need to open your computer's case.If you want to remove a hard drive for transport or storage, simply open the lock, pull on the caddy handle and take out the entire unit. It can serve as a data storage unit or be used right away in another computer.[IMGCAP(3)] If this confuses you, don't worry. Even industry insiders admit that conflicting nomenclature for the same products is confounding would-be buyers. It might help to do a general Web search using the term 'removable drive drawers.' You'll come up with about 10 pages of results, including a dozen or more manufacturers and some idea of the different names they use.External drive enclosures are portable or desktop cases designed to hold standard hard drives and to permit interfacing that drive to a computer. They contain electronics that bridge the hard drive's interface to common data interfaces, such as IEEE 1394 FireWire, Universal Serial Bus 2.0, PC Card or parallel port. If a power supply isn't provided through the interface it is part of the drive enclosure's package.At prices of $100 or less, external drive enclosures don't usually come with a hard drive. You can purchase a new hard drive of any capacity'up to 137G for a high-end IDE ATA drive'and install it into the enclosure for backing up existing files. You can also remove the hard drive from your desktop or notebook PC for storage and security purposes, or for use when you travel.Again, a Web search of the term will get you more information. By specifying FireWire, USB 2.0, PC Card or parallel port, you'll pull out the enclosures using these popular interfaces.Although some external drive enclosures provide SCSI interfaces, the ones in the chart below are all designed to hold a standard IDE hard drive and bridge their IDE interfaces to high-speed USB 2.0 and FireWire data buses. I prefer them for their easy setup, ease of use and speedy throughput.Why the sudden interest in removable IDE drive enclosures? According to Lava Computer Manufacturing Inc., a maker in Toronto, the reasons are fourfold:Drives with either FireWire or USB 2.0 interfaces are good choices for the following reasons:Speed. Both FireWire and USB 2.0 have enough speed to take advantage of the throughput capabilities of the hard drives fitted into the enclosures. Easy setup. Both FireWire and USB 2.0 represent good alternatives to SCSI drive interfaces, as they need no terminators or device IDs. They are easy to configure.Convenience. FireWire drives can daisychain directly to other FireWire devices for a total of 63 in all. USB 2.0 devices can be daisychained to other USB devices via hubs. Good support. Both FireWire and USB 2.0 are supported by popular OSes. FireWire is supported by Windows 98 Server Edition, Me, 2000 and XP; Macintosh OS 8.6 and higher, and Linux kernel 2.4 and higher. USB 2.0 is supported by Windows 98SE, 2000 and XP.The widespread use of USB 1.1 and the fact that USB 2.0 is backwards compatible with it means that you can use USB 2.0 devices right away, even with an older computer. But the full benefits of USB 2.0 will only be realized if a USB 2.0 port is on the host device.