IBM VERSION 5 SY44-5902-05 - Manual (Page 344)

SUID. System-unique identifier. A 12–character ID
that is assigned by the iSeries manufacturer to support
SOM software functions.
system ASP. The auxiliary storage pool where system
programs and data reside. It is the storage pool that is
used if the user does not define a storage pool. See also
auxiliary storage pool and user ASP.
Systems Network Architecture. The description of the
logical structure, formats, protocols, and operational
sequences for transmitting information units through
and controlling the configuration and operation of
networks.
system reference code. A group of characters that
identifies the machine status or a specific error
condition. The system reference code can be displayed
on the console from the problem log.
task. One or more sequences of instructions that are
treated by a control program as an element of work to
be accomplished. The basic unit of work from the
standpoint of a control program.
TCLK. In data communications, transmit clock.
TD. In data communications, transmitted data. Also
labeled XD.
TDE. Task dispatching element.
TI. In data communications, test indicator.
TSET. In data communications, transmitter signal
element timing.
TX A, B. In data communications, transmit clock (A
and B refer to each individual signal of a differential
pair of signals).
type D IPL. See installation IPL.
UA. (1) Unit address. (2) User agent.
Unattended IPL. An initial program load that is done
automatically by the system after the system power is
on.
UEPO. Unit emergency power off.
upgrade. To change or add to the system; to add
devices, features, or programs.
uninterruptible power supply. A battery installed
between commercial power and the system that
provides power to keep the system running, if a
commercial power failure occurs, until it can complete
an orderly end to system processing.
URC. Unit reference code.
user ASP. One or more auxiliary storage pools used to
isolate journals, journal receivers, and save files from
the other system objects that are stored in the system
ASP. See also auxiliary storage pool and system ASP.
vital product data. A structured description of a
device or program. For devices, it is recorded in the
device at manufacture and includes at least the type,
model, serial number, and installed features. It may
include the manufacturer’s ID and other fields. For
programs, it is compiled as a data area that
accompanies the program. Data includes the name of
the licensed program or Licensed Internal Code group,
the release and modification, the program module
names, the national language or languages selected,
and possibly other fields. Vital product data is
transferred from the device to the system and kept for
display. Vital product data is also visible on the device
name plate or a similar tag.
volume table of contents (VTOC). An area on a disk
or diskette that describes the location, size, and other
characteristics of each file, library, and folder on the
disk or diskette.
VPD. See vital product data.
VTOC. See volume table of contents.
word. 4 bytes.
XD. In data communications, transmitted data. Also
labeled TD.
X.25. In data communications, a specification of the
International Telegraph and Telephone Consultative
Committee (CCITT) that defines the interface to an X.25
(packet-switching) network.
330 Service Functions V5R2