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Time
The
time it takes for an optical drive to locate data
on an optical disk. Measured in milliseconds.
Data
Transfer Rate
The
speed at which an optical drive moves data from an
optical disk to an application. Measured in megabytes
per second (Mbps)
Dual-Head
Drives
Drives
that can read and write to either side of an optical
disk without flipping and re-inserting it. Dual-head
drives are exclusive to 12-inch optical drives.
Dual
Picker
An
enhanced version of a media picker that carries two
optical disks at the same time. A dual picker cuts
disk exchange time in half by inserting the requested
disk into an available drive first and then putting
the second disk back into its storage slot.
Export
To
remove an optical disk from an optical jukebox
HSM - Hierarchical
Storage Manager.
A jukebox manager that automatically and transparently moves data from
a hard disk to an optical jukebox based on rules such as file age and
file size.
Import
To
insert an optical disk into an optical jukebox.
Import/Export
Element
See
Mailslot.
Inventory
The
catalogue of media stored within an optical jukebox.
Jukebox
Manager
A
software program that manages read and write requests
to optical disks stored in an optical jukebox.
Magneto-Optical
(M-O)
A
type of optical disk that uses magnetic (magneto)
and laser (optical) technologies to write and read
data to and from the disk.
Mail
Slot
A
slot on the front or top of an optical jukebox through
which media is inserted into and removed from the
jukebox.
Media
Exchange Time
The
time it takes to move an optical disk from a drive
to a slot and another optical disk from a slot to
the same drive.
Media
Transport Element (MTE)
See
Picker.
Multi-Function
Drive
An
optical disk drive that reads and writes to WORM and
rewritable media.
Optical
Jukebox
An
automated storage device that holds many optical disks
with a small number of optical read/write drives used
to archive and store massive amounts of data. A robotic
arm moves optical disks from storage slots to the
drives. Also referred to as an optical library.
Phase-Change
A
recording process that uses laser light to convert
points on an optical disk from an amorphous state
to a crystalline state.
Picker
The
robotic component of an optical jukebox that moves
optical disks to and from storage slots and optical
drives. Also referred to as a media picker.
Shelf
See
Slot.
Single-Head
Drives
Drives
that can only read or write to one media surface at
a time. The disk must be flipped and re-inserted into
the drive in order to read or write to the other side. 5 ¼" drives
are single-headed.
Slot
An
area inside an optical jukebox where optical disks
are stored. A jukebox can store as few as 20 optical
disks or as many as 638, depending on the manufacturer
and model number of the jukebox.
Time
to Deliver Data (TDD)
The
total time it takes to deliver requested data back
to an application. This includes the time it takes
for the picker to fetch an optical disk, move it to
and insert it into an optical drive, spin up the drive,
locate the requested data, and transfer it back to
the application. Measured in seconds.
WORM
Write
Once Read Many. A type of optical media that allows
data to be written only once. Files cannot be overwritten. Commonly
used in regulated industries requiring permanent file
archives. Some regulatory agencies include the Securities
Exchange Commission, Nuclear Regulatory Commission,
and Food and Drug Administration.
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