Past Issues of Government Technology

Storage: More Bytes for the Buck

Our growing electronic history requires greater storage capacity and faster retrieval. Here's a report

by / March 31, 1996 0
The longer we compute, the more electronic history we create. It's amazing how the lowly bytes add up. All of a sudden, we have multi-gigabyte databases.

Another demand is multimedia. Real information is not just names and addresses, it's text, pictures and video. Count your file cabinets. Now, convert every piece of paper to 50,000 bytes. Need a calculator? It's almost as if we've been in the Pleistocene era 'til now (I'm not sure when that was, but it was before electric toothbrushes).

The bottom line is that there's no energy lost or gained in the universe. The 'ole adage -- that if the auto industry followed the computer industry, you could buy a Rolls Royce for $2.50 and get 500 miles per gallon -- is only half the truth. Usage is the other half. If the auto industry had followed us, we'd all be driving a million miles a day.

Following are the trends in tape and disk storage. We're always getting more bytes for the buck, but we can never get enough.

Pundits have prophesied the death of tape for years, but it is stronger than ever. Why? Tape is 25 to 100 times less expensive than disk. Tape cartridges have a 30-year life, and any decent disaster recovery program means you're taking data off site. So while it's not a direct-access medium, it doesn't have to be.

QIC tape still leads in desktop backup. The venerable 3.5" QIC-80 minicartridge originally started out with 125MB (uncompressed), but has risen to 200, 400 and 500MB with QIC-Wide, Travan and QIC-EX extensions.

QIC-Wide drives support a wider .315" tape. Travan drives support longer tapes as well as QIC-Wide, and QIC-EX cartridges, which come in both .25" and .315" formats, and extend capacity of both old and new drives even further. One company has gone to great lengths to make tape backup simple and cheap. Iomega's $150 "Ditto" QIC-80 Travan drive comes in parallel port and floppy interface versions, and its software makes it a button-click to back up.

There is still action in full-size 5.25" QIC data cartridges. Top models provide up to 25GB uncompressed, but this market is expected to dwindle.

DAT is 4mm audio tape adapted for data. DAT tapes are faster than QIC and hold from 2GB to 4GB, due to helical scan recording, which records data in diagonal chunks like videotape. DAT cartridges are also the smallest modules on the market. Street prices are $900-$1,700, and cartridges run $8-$20, so media cost is cheaper than QIC.

DAT usage is increasing on stand-alones and small to medium-sized LANs. DAT libraries are available that hold thousands of cartridges.

Exabyte introduced 8mm tape drives in 1987. Like 4mm DAT, 8mm uses helical scan, and there's more width to begin with. 8mm yields from 2.5GB to 7GB per cartridge. Street prices for drives are $1,500-$2,500 and cartridges about $20. 8mm is faster than QIC and DAT and is used to back up large LANs. Exabyte's Mammoth 20GB system should have been introduced by now and the cartridge price should be in the $30+ range. Exabyte and others make tape libraries that hold thousands of cartridges.

Last year saw outstanding growth in 1/2" tape cartridge technology called Digital Linear Tape. DLT was developed at Digital and later sold to Quantum, which now OEMs the drives. What's hot about DLT is its raw capacity and speed. A 10GB drive costs about $3,000 with cartridges around $38. Jump to 15GB for $3,500 and $50. DLT libraries are cost-effective too. For example, Overland Data in San Diego makes a 10-cartridge DLT library that holds 150GB for $13,000.

DLT is also faster than 8mm, DAT and QIC, providing up to a 1.5MB/sec data transfer for large backups. DLT is not as fast as 3480/3490 tape cartridges, but virtually swamps their capacity.

The old 1/2" reel-to-reel tape is still used and drives are still made for compatibility with legacy systems. However, most IBM shops have migrated to half-inch 3480/3490 cartridges. The 3490e has a raw capacity of 800MB, but is the fastest tape on the market. Storage Technology's Timberline drives use the ESCON channel or Fast SCSI-2 to achieve blazing 17 and 20MB/sec data transfer.

For the ultimate in tape backup, Storage Technology's Redwood library, which uses proprietary helical-scan 1/2" cartridges, can hold 6,000 50GB cartridges. That's 300 trillion bytes. (And you think your gigabyte drive holds a lot!)

The future of storage is optical. Since Sony introduced the first rewritable magneto-optic (MO) disc in the late 1980s, optical storage has grown steadily and has every chance of overtaking magnetic disks in time.

MO drives come in 5.25" and 3.5" form factors and use removable cartridges. Today's 2.6GB 5.25" drives support earlier 1.3GB and 650MB disks. 5.2GB are planned for 1997. The smaller 3.5" drives use 128MB and 230MB cartridges, and 650MB is around the corner. There is a difference. The 5.25" media is dual sided. You have to flip the disc to get to the other half. A 2.6GB drive is really 1.3GB online. Not so with the 3.5" media, which is single-sided.

Pinnacle Micro should have introduced its Apex MO drive by the time you read this, which can store 4.6GB (2.3GB per side) and read-and-write industry-standard 2.6GB discs. This is breakthrough technology, especially at a $1,695 MSRP per drive and $195 per cartridge. With a 17ms access time and 6MB transfer rate, it's neck and neck with many hard disks.

Panasonic stands alone with its phase-change technology, which can write data in one rotation. MO currently requires two passes, but that could change.

Optical libraries store from a handful to several thousand platters and can use multiple drives to read them. You can back up onto optical creating an identical copy of a hard disk. Upon failure, just execute directly from the optical disc and you're up and running much faster than tape.

Using its Apex technology, Pinnacle offers a 5TB library for $200,000. That's a million times as much online storage as the first hard disk. A 75GB library costs $6,000.

Optical discs have a life expectancy of 30 years, but WORM disks will last 100. WORMs are used for archiving, and the bits in these "ablative" discs cannot be reversed. The 12" and 14" systems are still being manufactured and used, but smaller diameter WORMs have given way to multifunction MO drives that emulate the read-only nature of WORMs. Firmware in the MO drive makes sure the data cannot be changed. Multifunction MOs and CD-Rs are shortening the life of ablative WORM disks.

CD-R is used to record data onto blank CD-ROMs. Also called "one-offs" (one disc at a time), they are used to create master discs for CD-ROM manufacturing. CD-R has become popular because the drives have dropped from well over $10,000 to less than $1,000. Pinnacle once again lowered the boom to $995 with major companies following suit, including HP, which offers a caddyless internal unit for the same price. A caution: the gurus say caddies keep the media cleaner while recording.

CD-R is appealing for write-once applications, because CD-ROMs are now as standard as floppies. CD-R provides 650MB of archival space. It may take half an hour to record one disc, but it provides a way to distribute large amounts of information to a small number of offices. Or, send one disc to a CD manufacturer who will press all you need for as little as a buck apiece.

CD-R is expected to evolve into CD-E this year, which means a rewritable 650MB CD disk. CD-E drives can read CD-ROM and CD-R disks, but existing CD-ROM drives cannot read CD-E disks under the currently-proposed technology. There is speculation that the CD-E disc will be abandoned for the really big banana (see DVD below).

With the security and unlimited storage advantages of removable disks, one might wonder why only one company has owned the market to date. In 1982, Syed Iftikar founded "Sy's Quest" and made a custom removable drive for the military. In 1986, SyQuest introduced the 5.25" 44MB drive, and later upped the ante to 88MB and 200MB. In 1993, it introduced its first 3.5" drive with 105MB and last year raised it to 270MB. Street prices for the 3.5" drives are about $500 and $75 for the cartridges.

Right now, SyQuest disks, especially the 5.25", are the de facto standard at graphics service bureaus. Need to send a huge PostScript file to an imagesetter? A SyQuest is a best bet. At 13.5 milliseconds, they are fast, so you can use them as a second hard drive with unlimited storage.

But SyQuest is starting to face competition. Iomega introduced its 1GB Jaz drive, a fast, removable magnetic disk that costs just a tad more than a SyQuest and offers three times the capacity. Jaz cartridges are only $99. In order to keep itself number one, SyQuest plans to introduce a 1.3GB drive just about the time you read this. It expects to keep its lead with prices the same as or perhaps a few dollars less than the Jaz. Unfortunately, although the 1.3GB SyQuest uses 3.5" media, it will not be able to read or write its own 105MB and 270MB disks.

Both SyQuest and Iomega have introduced what each is hoping will become the storage solution between the floppy and high-capacity removables. SyQuest's EZ135 disk and Iomega's Zip disk provide 135MB and 100MB capacities respectively with drives that cost $200 and less-than-$20 media. The EZ135 disk holds a third more data, and because it's a hard disk (the Zip is a floppy), its access time is twice as fast as the Zip. Both units are doing well, but the Zip disks are flying out of the Iomega warehouse.

Sony released its lightweight, portable MD DATA disc with a tad more capacity than the EZ135, but at a hefty price. This 2.5" optical disc is the data counterpart of the audio MiniDisc, which has been shipping for over a year. The street price should be about $600 with $25 cartridges. It runs on three AA batteries or can be plugged into the wall for a charge. It can also play MiniDiscs, but not record them.

Sony invented the 3.5" floppy, which, thank God, has finally obsoleted the 5.25s. But even with Sony's immense marketing clout, it's hard to believe a $600 drive will eclipse either SyQuest's or Iomega's offerings. The Zip, EZ135 and MD DATA all offer appealing media prices for backup, but $20 is still 80 times the cost of a floppy. We could sure use a 100MB floppy-like disk that costs a buck!

Iomega's removable floppy disk-like Bernoulli Box was designed from principles demonstrated by 18th century Swiss scientist, Daniel Bernoulli. In 1983, the Bernoulli cartridge was 10MB. Capacities increased to 20MB, 44MB, 90MB and 105MB, and most recently 230MB. Street price for the 230MB drive is about $500.

Bernoullis are known for their high reliability, especially if you have to send them via mail. At 18 milliseconds, they provide respectable speed.

The Digital VideoDisc, or DVD, is yet another storage offering coming down the pike that could have more impact than anything in this article. The disc is the same size as a CD-ROM, but has seven times the capacity: 4.7GB instead of 650MB. Plus, you can record on the other side to double that amount. What's more, a dual-layer version is planned that yields 8.5GB per side. DVD players are expected to play/read CD, CD-ROM, CD-I and Video CD discs.

DVD uses MPEG-2 compression for approximately 135 minutes of video per side, which approaches the quality of analog LaserDiscs. This is not a guaranteed length, because the data rate varies depending on how much action takes place in each frame.

Both the computer and movie industries have worked on DVD to make it the next CD-ROM standard and primary digital movie medium, superseding Video CDs and analog LaserDiscs. What makes this a potential killer product is that the DVD is designed to be rewritable, unlike the problem we're having trying to make a read-only CD-ROM erasable. A rewritable DVD could squash the CD-E before it ever gets here. Because there's a huge consumer market waiting for this, the drives and media could become very affordable much sooner than expected.

Watch out hard disk vendors, optical disc vendors and tape vendors. Watch out everybody! Who knows, the DVD could become the next floppy.

Not enough choices? How about a little science fiction called holographic storage. Using two laser beams to create a hologram of binary data, 10,000 one-million-bit pages can fit within a cylinder of optical material one centimeter long by one millimeter in diameter. Holographic storage can potentially store 10 megabytes on the head of a pin with transfer rates 1,000 times greater than today's rates. Compare the sublime magic in the chip to the ridiculous "washing-machine" actions of whirring motors and heads jutting in and out on disk drives. There will be a time when all storage is solid- state.

Some of the facts and figures in this article were gleaned from reports from Freeman Associates. Freeman Reports provide exhaustive detail on the technology, capacities, market share and future trends of disks and tapes. Contact Freeman Associates, Inc., 311 E. Carrillo St., Santa Barbara, CA 93101, 805/963-3853.

Alan Freedman's Computer Desktop Encyclopedia is an award-winning source of computer terminology, concepts, products and players with more than 9,000 definitions from micro to mainframe. The fully-hypertexted Windows version includes 200 illustrations, takes 7MB hard disk space and costs $34.95 from The Computer Language Company, 215/297-8082 (Fax 8424).


Bit (b) From "BInary digiT." A single digit in a binary number (0 or 1). A bit is like a light bulb, either on or off, a magnetic spot on disk or tape.
Byte (B) Groups of bits make up storage units in the computer. The most common is the byte, made up of eight bits, and equivalent to one alphanumeric character. The above article on storage and this sidebar together contain about 14,700 bytes.
Kilo (K) Thousand. KB refers to Kilobyte. Kb refers to kilobit.
Kilobyte (KB) A kilobyte is technically 1,024 bytes, since it's a binary number (1-2-4-8-16-32-64-128-256-512-1024). Equals about 1/3 page of text.
Mega (M) Million.
Megabyte (MB) 1,048,576 bytes, about 365 pages of text, approximately the storage capacity of a high-density 3.5" floppy disk. The 68-page February issue of Government Technology occupied 480 megabytes of memory for text, photographs, ads, etc.
Giga (G) Billion.
Gigabyte (GB) 1,073,741,824 bytes. About 395,000 pages of text, or 1,000 average-sized books.
Tera (T) Trillion
Terabyte (TB) 1,099,511,627,776 bytes. About 400 million pages, or the text contained in a library of a million books.
Reference: The Computer Glossary, Seventh Edition, By Alan Freedman, 1995, The Computer Language Company Inc.