The standard system cabinet can hold up to four IP12 drives in the lower bay area. Multiple4.6.3 Tape
external "low-boy" or "tall-boy" racks can be obtained to hold additional drives up to a
maximum of 32.
4.6.4 Exabyte 8mm
As with the hard disk technologies for secondary storage, there are a number of options for
digital tapes to back-up, restore, and share data.
The 8mm Exabyte tape drives offer the largest storage capacity. These drives utilize the same
standard 8mm tapes as camcorders for very low cost media. This low media cost is combined
with very high data density to enable the storage of up to 2.3GB of data on a single tape. This
is extremely useful forthe off-line storage of large databases or complete disk back-ups. The
Exabyte drive would typically be installed in the upper front drive bay of the removable drive
4.6.5 1/4" Data Cartridge
Less expensive and more common are the 1/4" data.cartridge tape drives. These are the drives4.6.6 1/2" Tape
that are found on most workstations and offer a data capacity of up to 150MB per tape. When
operating system and other option software is distributed, this is typically the media utilized.
The tape media for these drives is specialized for the computer industry, however, so the media
cost can be as much as 10x that of the 8mm media. The 1/4" drive, however, is roughly 1/3 the
price of the 8mm drive, so cost efficiency will be at least partially determined by the quantity
of media required.
Sometimes it is important to be able to transfer data not only to and from off-line storage or
between workstations, but to and from mainframes utilizing large 1/2" tapes, not data
cartridges. In these cases (such as reading DMA DTED data), the SkyWriter system can
incorporate a 1/2" tape drive which can be mounted in the lower drive bay.