IBM TS2900 Setup, Operator, And Service Manual page 241

data check. A synchronous or asynchronous indication
of a condition caused by invalid data or incorrect
positioning of data.
dc. Direct current.
DCS. Designated Cleaning Slot
degauss. To make a magnetic tape nonmagnetic by
means of electrical coils carrying currents that neutralize
the magnetism of the tape.
degausser. A device that makes magnetic tape
nonmagnetic.
degradation. A decrease in quality of output or
throughput or an increase in machine error rate.
degraded. Decreased in quality of output or
throughput or increased machine error rate.
deserialize. To change from serial-by-bit to
parallel-by-byte.
detented. A part being held in position with a catch or
lever.
device. Any hardware component or peripheral, such
as a tape drive or tape library, that can receive and send
data.
device driver. A file that contains the code needed to
use an attached device.
DHCPv6. The Dynamic Host Configuration Protocol
for IPv6. Although IPv6's stateless address
autoconfiguration removes the primary motivation for
DHCP in IPv4, DHCPv6 can still be used to statefully
assign addresses if the network administrator desires
more control over addressing.
DH group. Diffie-Hellman group.
DIAG. Diagnostic section of maintenance information
manual.
differential. See High Voltage Differential (HVD).
direct access storage. A storage device in which the
access time is independent of the location of the data.
display contrast. The brightness of the display on the
Operator Panel.
DLL. Dynamic Link Library. Microsoft's
implementation of the shared library concept. These
libraries usually have the file extension dll, ocs (for
libraries containing activeX controls, or drv (for legacy
system drivers).
DNS. Directory Name System. This allows the library
to recognize text-based addresses instead of numeric IP
addresses.
download. (1) To transfer programs or data from a
computer to a connected device, typically a personal
computer. (2) To transfer data from a computer to a
connected device, such as a workstation or
microcomputer.
DRAM. Dynamic random-access memory.
drive, magnetic tape. A mechanism for moving
magnetic tape and controlling its movement.
Drive Not Configured. This message occurs during
the first boot after a factory settings restore is executed.
This is not a real issue since it takes the library a while to
configure.
DRV. Drive.
DSA key. Encryption key type.
DSE. Data security erase.
DSP. Digital signal processor.
E
EBCDIC. Extended binary-coded decimal interchange
code.
EC. Edge connector. Engineering change.
ECC. Error correction code.
EEPROM. Electrically erasable programmable
read-only memory.
EIA. Electronics Industries Association.
EIA unit. A unit of measure, established by the
Electronic Industries Association, equal to 44.45
millimeters (1.75 inches).
eject. To remove or force out from within.
EKM. See encryption key manager.
electronic mail. Correspondence in the form of
messages transmitted between user terminals over a
computer network.
e-mail. See electronic mail.
encryption. A method of storing data in a format that
helps protect data from inadvertent or deliberate
compromise. An encryption-enabled drive contains the
necessary hardware and firmware to encrypt and
decrypt host tape application data. Encryption policy
and encryption keys are provided by the host
application or host server.
I-3
Glossary