Research Computing
Computer Bits
A condensed summary of new computer technologies and products that
will affect the future of computing.
Disclaimer:
Reviews and discussions are not intended to be comprehensive, nor
should they be viewed as endorsements of the technologies or the products.
Storage Devices
- Removable Hard Drives
- Syquest EZ135
- IOmega ZIP drive
- IOmega JAZ drive
- CD-R Drives and DVD
- New Products
- The Floptical Drive - LS-120
- The Western Digital Swappable hard drive
- On the Horizon
- The Fibre Channel Specification
Storage technologies are in a period of rapid evolution, with disk storage
capacities, transfer rates, and cost/megabyte all changing almost daily. Cost
per megabyte of storage has plumetted: in 1985 a bargain desktop drive cost
$12/MB, with a throughput of 0.5 MB/sec and a capacity of 20MB. In 1990 the
cost was $3/MB, with a throughput of 1.5MB/sec and a capacity of 80MB. As of
12/95 a typical `middleweight' desktop computer is shipping with a minimum of a
540 MB disk, with 1GB common. A typical 1GB disk today costs $0.28/MB and
offers in excess of 5MB/sec throughput. By 6/96 a typical midrange computer
comes with 1.6GB of storage and 16MB RAM.
The Future: The cost of storage will continue to decrease, and new
technologies are being developed to meet the demand for increased data
transfer. Today, the most common storage interfaces for desktop computers and
workstations are the SCSI-2 specification and EIDE specification. Both of these
interfaces are limited to about 10MB/sec. Ultra SCSI is a bidirectional
technology designed to reach 40MB/sec. New interfaces (see the Fibre Channel
specification) are under development to raise this limit to 100 or even
200MB/sec, and dramatically increase the distance between the storage device
and the computer.
The EZ135 is based on the Syquest 270MB technology, but only writes on a single
side of the removable hard drive cartridge to reduce manufacturing costs.
Available with IDE or SCSI interface.
Comparison: The IOmega ZIP drive is the closest competitor to the EZ135.
The Syquest stores more information (130 vs 100 MB), is faster (14ms seek vs
20ms, 2.5MB/sec sustained data transfer vs 1.2MB/sec), the cartridge is better
isolated so the media is likely to last longer, and the case is larger and more
rigid. Cons: The cartridges are larger, are more susceptable to impact,
the unit weighs more, and ejecting a disk requires 3 actions: unmounting the
disk from software, hitting a button on the front of the unit, and finally
ejecting the disk using a lever (in other words, the standard set of actions
for a syquest drive) vs. software disk unmounting and auto-ejection for the
ZIP.
Street Price: $200 (IDE), $220 (SCSI), disks $18-20
12/95
The IOmega ZIP drive is a small, light alternative to a 3.5" floppy drive, and
unlike flopticals, is available today. One disk stores just less than 100MB
when formatted. The unit is quiet, the disks are flexible and about the width
of two standard floppies. Cons: The ZIP drive has definite drive
compatibility problems on SCSI-equiped computers, especially with SCSI printers
and SCSI scanners. Likewise the parallel port interface ZIP drivers with
Windows95 and Windows NT are extremely finicky and on a number of computers
have simply not worked.
Comparison: See Syquest EZ135 for a comparison of the ZIP and the
EZ135.
Street Price: $180 (Parallel), $200 (SCSI), disks $15
11/95
The IOmega JAZ drive is a small, light alternative to a 3.5" floppy that
addresses many of the problems with the ZIP drive. Disks are available in
either 500MB or 1GB capacities. The unit is quiet, the disks are small, and
access is extremely fast, with 6MB/sec ratings and better than 3MB/sec real
world throughput, or more than 5x faster than the ZIP. Cons: There don't
seem to be any at this point.
Comparison: See Syquest EZ135 for a comparison of the ZIP and the
EZ135.
Street Price: $499 (internal SCSI), $599 (external SCSI), disks
$100/1GB
6/96
Compaq
QuickSpec Sheet for the LS-120.
The Floptical Drive is a 3-1/2" magneto-optical disc that is scheduled to ship
second quarter 1996. A Floptical disc will hold 120 MB of data and is
manufactured by MKE Limited. The Floptical was jointly developed by 3M,
Matsushita Electric Industrial Co, and Compaq Computer Co. Estimated street
price is $150. For specs, see compq
QuickSpec Sheet for teh LS-120.
12/95, shipping 2nd quarter 1996
Western Digital Corp. is gearing up for the release in September 1996 of an
ultrathin removable hard drive that can be swapped between laptop and desktop
computers.
The technology is licensed from JTS Corp. in San Jose, Calif. JTS already is
shipping its version of the drive, code-named Nordic, to Compaq Computer Corp.
for fixed installation in forthcoming laptops.
In its removable form, the passport-size drive fits in to a PC docking bay and
does everything a fixed hard drive does, from running the operating system to
storing data. Business travelers will be able to move the drive between
desktops and notebooks. Multiple users will be able to share one PC but use
different hard disks. Western Digital CEO Charles Haggerty estimates the price
will be between $200 and $300.
The JTS drive transfers data almost 12 times as fast as the Zip and more than
29 times as fast as the LS-120. Drive capacities have not been announced.
Computerworld, 7/1/96, shipping 3rd quarter 1996
A Fibre Channel Specification (developed by AMP and Western Digital) was
recently proposed jointly by Sun Microsystems and Compaq Computer Co. for use
in their mid-level servers. The disk drives incorporating the high speed Fibre
Channel interface will be first used in mainframe and high-end servers.
Seagate Technology andWestern Digital have begun to ship units and are expected
to reach full production in first quarter 1996. The Fibre Channel interface
allows data transfer rates of up to 200M bytes/sec, with the first units
capable of 100 MB/sec. The specification also permits cable lengths of up to 30
meters in length for copper, and fiber optic connections up to 10 kilometers.
This site created and maintained by
- Warren A. Kibbe, Ph.D.
Technical Director of Research Computing, Basic Sciences
Email: WAKibbe@nwu.edu
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