Removable Storage Keeps on Track toward Faster Access, Bigger Capacity

By Bruce Schneier
MacWEEK
November 16, 1992

Since 1984, RAM capacity has climbed more than tenfold, from 128 Kbytes to 256 Mbytes. CPU power also has increased dramatically, from the sluggish 8-MHz 68000 to the 33-MHz 68040 in the Quadra 950.

Yet, the capacity of floppy disks - that almost ubiquitous storage media - has lagged far behind the others, barely tripling from 400 Kbytes to the current 1.4-Mbyte disks.

Desktop publishing, digital photography, multimedia and CAD all have put pressure on vendors for storage media that is much larger than floppy disks. To fill this need, several different storage technologies have emerged, each with different storage capacities and formats.

Yet with the variety of solutions available, managers now wonder what the future holds for removable storage. The good news is that removable storage will increase in capacity; the bad news is that it is not going to happen next week.

SyQuest Drives

The most common solution for high-capacity removable storage has been SyQuest drives. At an average mail-order price of $104 for the 88-Mbyte drives and $65 for the 44-Mbyte disks, they are an inexpensive way to add high-capacity storage to a Macintosh.

According to SyQuest Technology Inc., yet another flavor of SyQuest drives is on the way. "We'll have 3.5-inch 105-Mbyte [SyQuest] SCSI drives by next year," said Joe Levine, vice president of product planning at SyQuest.

While capacities are going up, seek times are going down. Current SyQuest drives have seek times of 20 milliseconds, but that will improve. "There are better algorithms - better magnetics. The 105-Mbyte drive will have a seek time of under 10 milliseconds," Levine said.

How far can SyQuest technology go? SyQuest has announced a 2.5-inch drive for portable computers, and Levine hinted at even smaller-size products. Levine said, "Everyone expected magnetic storage to peak out, but there are major improvements in head and media technology that are going to allow magnetic storage to keep growing."

Bernoulli Boxes

For several years, the only other removable storage option was a 40-Mbyte Bernoulli disk from Iomega Corp. Currently, the 5.25-inch Bernoulli removable cartridge holds up to 90 Mbytes.

"We believe the technology can be pushed at least an order of magnitude over where it is today," said Mike Joseph, vice president of marketing at Iomega. "We will be growing our capabilities as fast as the Winchester industry." For comparison, Winchester drives generally double in capacity every 18 months to two years.

Access speed also will increase. According to Joseph, Bernoulli boxes were forced to perform slower than they could because of the SCSI interface. SCSI-2 will eliminate this problem. "As SCSI gets faster, we can tap more and more power of the drive," he said.

Magneto-optical Drives

For some, 100-Mbyte disks are just too small. "We regularly deal with files in the hundreds of megabytes," said Jay Samit, president of Jasmine Multimedia Publishing Inc, a multimedia production company based in Los Angeles.

For users such as Samit, magneto-optical drives are one answer. These 3.5- or 5.25-inch drives use a laser for reading and tracking, and both a laser and magnet for writing.

The current 3.5-inch magneto-optical standard capacity is 128 Mbytes, although there are some nonstandard disks and drives that store 256 Mbytes per disk.

However, some vendors note that the nonstandard 256-Mbyte 3.5-inch capacity may be only an interim step. "[Most vendors] will probably just pass 256 Mbytes and go to 512 Mbytes," said Dan Harrell, product manager at DGR Technologies, a hard disk and magneto-optical storage vendor based in Austin, Texas.

These drives cost about $1,000 for a 128-Mbyte mechanism and $55 for a disk - but their 40-millisecond seek times are nearly comparable to hard disks.

Akyra Pagoulatos, marketing manager for the Rewritable Optical Division of Sony Corp. of America in San Jose, Calif., doesn't foresee any substantial speed improvements for 3.5-inch drives. "To improve speed, you need different schemes. You can make the head only so light and spin the drive so fast. You may need a different media that is capable of spinning faster," Pagoulatos said.

More MO

The current standard for 5.25-inch magnetic-optical drives is 650 Mbytes, although again there are nonstandard drives on the market. Several companies have announced 1.3-Gbyte magneto-optical drives that are backward-compatible with current cartridges.

"You'll see [larger-capacity] products by June of next year," said Scott Blum, vice president of marketing at Pinnacle Micro Inc. A 2.6-Gbyte 5.25-inch standard is another two and a half years away, Blum said.

According to industry experts, seek times for 5.25-inch magneto-optical drives will improve. "It will come down by half in six months," DGR's Harrell said. Some industry players see most of the improvement in the 5.25-inch arena, where some companies are already claiming average seek times in the 20-millisecond range.

Sony's Pagoulatos pointed to two technologies, a one-pass writing scheme to increase speed and Zone CAV to more efficiently pack sectors on a disk, as near-term improvements to the technology.

Another magneto-optical technology, called thermal eclipse recording, is likely to push the storage envelope even further. "It packs bits so tightly that you can put 4.3 Gbytes on a single-sided 5.25-inch disk," Pagoulatos said.

Don't rush to your computer store, though. According to Pagoulatos, this technology is at least five years away.

Floppy Alternatives

Recently 3M Corp. of St. Paul, Minn., announced a 4-Mbyte, 3.5-inch floppy. Unlike the current 1.4-Mbyte floppy, this is based on a barium-ferrite media formulation. Researchers think they can push this technology to 100 Mbytes or more. "These disks represent the first in a new generation of products," said Dave Tynan, market development manager for disks at 3M.

Floptical drives use regular 3.5-inch magnetic disks but pack much more data on a disk by using an optical guidance system that follows special tracks stamped on the disk's surface. The drives not only read and write special 20-Mbyte floptical disks, but also 1.4-Mbyte floppies. "This is going to eventually replace floppies," said Dave Broudy, product manager at Procom Technology Inc. of Irvine, Calif.

"Flopticals will probably go to 40 Mbytes in two years," Broudy said. Although speeds also will improve, they will not approach those of hard drives or magneto-optical drives. Said Broudy, "It's still a floppy drive: You have slow seek and slow transfers."

Is the floppy doomed to obscurity in the face of all these technologies? "Software companies will continue to distribute software on a vehicle with very low cost and a large installed base," said Bob Katzive, vice president of Disk/Trend Inc., a market research company in Mountain View, Calif.

Apple's Next Step

Apple traditionally has been conservative with storage technology. The next logical step is a 2.8-Mbyte format. The Mac's floppy controller chip could handle the faster data rate, and it would be easy to adapt the disk interface; unfortunately, experts feel it probably would be incompatible with the ancient 400-Kbyte floppies.

However, some wonder if that small a jump would be worth the cost.

"Apple is a mass-market company; it needs to take the long view. Moving to a 2.8-Mbyte drive is only a short-term solution," said Mike Bentley, president of Crenelle Inc., a multimedia software developer in Chicago.

Ultimately, whether Apple moves to a higher-density floppy, a floptical drive, a magneto-optical drive or something else entirely, there still will be plenty of new third-party removable storage products to satisfy the needs of the marketplace.

"CD-ROM is not a replacement for floppy disks, nor can it be compared to hard disks," said Allen Adkins, president of Optical Media International in Los Gatos, Calif. "CD-ROM is a publishing and distribution media."

The 640-Mbyte disk capacity, coupled with the low costs for players and media, is making CD-ROMs more commonplace. Some software products, such as Macromedia Inc.'s MacroMind Director and most of Apple's Macintosh development tools, ship on CD-ROM. "You can't be a Macintosh developer without a CD-ROM drive," said Mike Bentley, president of Crenelle Inc., a multimedia software developer based in Chicago.

The current generation of CD-ROM players have a data transfer speed of about 350 Kbytes per second. Pioneer Communications of America Inc. has announced a CD-ROM drive that is four times as fast. "Within 18 months there will be a [write-once] recorder that fast," Adkins said.

The emergence of write-once CD-ROM is making the media even more versatile. Users who need to make multiple CD-ROM masters or need to test CD-ROM programs can buy an $8,000 write-once recorder that can produce $35 CD-ROMs that can be read on any player. "It is an ideal system for limited CD-ROM production (less than 50 copies) and will eventually be competitive with tape for data archiving," Adkins said.

earlier essay: Flash Memory Offers Potential for Compact Storage Solution
later essay: Inside the PCMCIA Storage Standard
categories: Non-Security Articles
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