The evolution of storage: yesterday, today, & tomorrow

by Alan Zisman (c) 1996. First published in Computer Player, May 1996

Where does your data go when you flip off the power switch?

Unless you?ve saved your file, the answer, of course, is to that big bit-bucket in the sky?in other words, it?s gone unless you?ve stored it. Your computer needs storage... not just to save your data files, but to store your applications, and even the operating system. Without being able to read and write files, your computer would be a mere shadow of itself.

Not useless, mind you?we use a lot more computers than we?re aware of, mostly in the form of embedded processors. CPUs with a relatively small amount of instructions permanently burned into ROM chips, in our cars, cameras, microwaves, and VCRs. But without storage, these computers are limited to a single purpose... not really computers as we know them.

Yesterday...

For the first personal computers, storage was slow and unreliable... paper tapes on the pioneering Altair; cassette tapes on later Commodore VIC-20s, for example. Even the first IBM Personal Computer had a port for a cassette player. But a big breakthrough came when Apple co-founder Steve Wozniak designed a floppy-drive interface for the Apple II, permitting it use relatively fast cheap and reliable disks. Even though floppy disks were an extra-cost add-on for those early Apples and IBMs, they were clearly the way to go.

Floppy diskettes shrank in size and grew in capacity, from the 160kb 5¼? disks of those first  IBM PCs to the 360kb double-sided, double-diskette disks of IBM?s XT to the 1.2 meg 5¼? AT diskettes. Smaller, more durable 3½? diskettes were first popularized as 400kb single-sided models on 1984s ground-breaking Apple Macintosh, growing in capacity to 800kb and then 1.44 meg models, now standard on both Macs and PCs. (And yes, these hard-shelled diskettes are still floppy disks... break one open and see).

IBM tried to establish a higher-density standard, 2.88 meg diskettes, in the late 80s, but these have failed to become popular?drives and disks are rare and expensive; other than that, floppy disk technology has pretty much remained stagnant, with the older  5¼? being left off most new computers to make room for CD-ROM players.

Even though a 1.44 meg diskette holds almost ten times as much as the initial generation of floppies, even users of early personal computers ran into problems... You quickly ended up with a collection of floppies, and had to shuffle between them. And applications soon required multiple diskettes?you might have to swap disks to spell check your word processor file.

Mainframe and minicomputer users had been making use of a technology that used rigid platters?hence the name hard disks. Some models were removable, but most stayed in a permanent stack, in a unit with multiple platters?IBM (which often prefers its own names for things) called these fixed disks. But these were too big and too expensive for personal computer users. Even when they were scaled down to 5¼? size to fit in a PC, a hard drive with a then massive-seeming 5 megabytes of storage might cost $2000 or so.

A breakthrough occurred in 1983, when IBM released its XT model?basically a barely upgraded original PC, but with a 10 meg hard drive included. A year later, the AT doubled that, with a 20 meg drive...giving owners of that $5,000 machine visions of unlimited storage. Room for all the key business programs of the mid-80s, 1-2-3, WordStar, and dBase, along with your data.

Even then, there were alternatives. Some users preferred removable storage, and companies like Iomega and Syquest provided it. Prime Minister John Turner, in his Vancouver office, for instance, used a PC together with a unit offering twin 10-meg Iomega Bernoulli boxes; a total of 20 megs of removable storage.
 

Today...

Hard drives have shrunk in size and cost, while growing tremendously in capacity and reliability.

In 1988, I purchased a 40 meg hard disk on sale for $400... today, a gigabyte (a billion bytes?25 times as large) drive is about ¼ the size, and little more than half the price. And by the end of the year, expect that gigabyte drives will be the standard capacity offered on computers aimed for home and business use.

Inside, these units still look like miniatures of a 1970s-style hard drive?a stack of metal platters, spinning at high speed. But breakthroughs in the technology of packing magnetic information onto the disks has made it possible to manufacture small, high-capacity drives for the same cost as the much less capable units of even two years ago.

At the same time, newer PCs include support for larger drives?so-called Logical Block Addressing (LBA) built in, making it easy to add drives larger than 512 meg... formerly a limitation that could only be overcome with special hardware or software.

Drives are available in two basic flavours. EIDE is the common standard for PCs... now that the 512 meg limitation has been bypassed, permitting cheap, high capacity drives. SCSI, first made common on Apple Macintosh models, also permits high capacity drives, and can provide performance and features beyond EIDE. SCSI remains non-standard on PCs, however, and as a result, SCSI drives cost more than their EIDE equivalents (and users also typically need to purchase a $200-300 adapter).

Tomorrow?

It seems clear that hard drive capacities are going to continue to increase, at least for a while, with gigabyte capacities becoming standard, and multi-gig units increasingly common and affordable.

The biggest changes, however, seem to be happening with removable storage. Since the adoption of the 1.44 meg floppy almost a decade ago, this area had been pretty stagnant; users needing higher capacities (typically graphics professionals, using Macs) tended to standardize on the 40meg Syquest cartridges, which, requiring SCSI, were rare among PC users.

The past year has changed all that. Iomega?s ZIP drive, a $300 (CDN) unit using 100 meg disks costing about $20 each has threatened to become a new standard. It?s available in SCSI models for both Mac and PC, and in a parallel-port PC unit, which while slower than the SCSI version can be easily moved from computer to computer.

(SCSI users may prefer Syquest?s faster and higher capacity EZ-135... unfortunately, the Syquest and Iomega models can?t share disks).

But 100-135 megs may not be enough, and both Iomega and Syquest are among the companies offering even higher capacity removable storage at relatively affordable prices. Again, Iomega appears to be first off the mark?their Jaz drive is just starting to become available, offering both internal and external (SCSI only) drives using massive 1 gig cartridges. At about $600 (US) for the drive, and $100 (US) per cartridge, these are initially pricier than hard drives, but become increasingly economical as more cartridges are purchased. And performance promises to be within the range of  hard drive performance.

Even tape is making a bit of a comeback. Slow and linear, it isn?t going to replace hard drives or diskettes for storing often-used programs or data, but it has built a niche as a low-cost media for back-up purposes. Recently, low cost drives have become available from a number of companies, using 800 meg Travan tapes. At $40 per tape, these are quickly replacing the older but more expensive drives running QIC-80 style tapes. (The Travan units can also use the older QIC-80 tapes). And parallel-port tape drives, such as MicroSolutions? BackPack or Iomega?s Ditto can be easily used to backup multiple PCs? data, while costing only around $250 (CDN). Note that as with the parallel port ZIP drive, parallel port tape drive performance can be increased dramatically using enhanced or ECP parallel ports.

Again, SCSI provides the high end alternative. SCSI-based DAT tape drives can archive a couple of gigabytes of data onto a standard digital audio cassette tape... about $30 per cassette, but the drives themselves still cost around $2,000.

For a time, it seemed as if recordable-CD-ROM (CD-R) would become a new standard medium, but I?m pessimistic, at least in the short term.

Writable CD drives remain expensive, hovering around $1,000 or more, and more important, difficult to use. Users need a fast, big hard drive, with a CD?s worth of unfragmented free space (about 650 megs). Even then, recording remains hit and miss?users often find they?ve ruined a $20 use-once blank disk. And the CD standard is about to change?from the 650 meg current disks, to the 3.7 gig (higher capacities later) DVD (also known as SD-ROM). Expect high-priced DVD units near the end of the year, with a couple of years before this becomes a widespread standard.

For the near future, at a minimum, look for gigabyte or larger EIDE hard drives in entry-level machines. Hopefully, enhanced (or ECP) parallel ports will become standard, as more and more devices are sold making good use of the added performance and convenience of these ports. Built-in SCSI may become more common on mid-level machines, making it possible for buyers of these units to make use of devices such as the Jaz drive; higher end machines may even start offering internal Jaz drives for fast, high-capacity removable storage.
 
 
 
 
 



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Alan Zisman is a Vancouver educator, writer, and computer specialist. He can be reached at E-mail Alan