SNA IMF/XL Node Manager's Guide (30293-90010)

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opening files, opening
communications lines, or
transmitting data over a
communications line.
L
ldev: See logical device.
ldn: Logical device number. See
logical device.
link: The physical or logical
connection between two devices
in a network.
logging: The recording of
significant events that may be of
use to the user at the time they
occur. This is distinguished from
tracing, which is the recording of
events for future use.
logical device (ldev): Adiscfile,
a set of disc files, or a physical
device associated with a data
stream between a host and a
remote system. An HP logical
device is identified either by a
number or by a device class name.
For SNA IMF, ldevs are identified
by ldev numbers; device class
names are not supported.
Logical Unit (LU): A program
or a set of programs within a node
that provides access to an SNA
network for an end user. A logical
unit can support two types of
sessions: (1) an LU-SSCP session
and (2) an LU-LU session. The
logical unit formats message
units, displays information, and
handles error recovery. Multiple
logical units can reside in an SNA
node.
Logical Unit (LU) class: A set
of logical units on the HP 3000.
For SNA IMF, an LU class may
contain multiple LUs.
Logical Unit Type 1 (LU.T1): A
session between an application
program and one or more data
processing terminals. The
environment may be interactive,
distributed processing, or batch
data transfer. Character-oriented
printer devices, batch support
(RJE), and the SNA Character
String (SCS) are supported.
Logical Unit Type 2 (LU.T2): A
session between an application
program and one 3270-type
display station using interactive
data transfer. IBM 3270 Data
Stream Capability (3270 DSC)
and 3270-type display station
support is provided.
Logical Unit Type 3 (LU.T3): A
session between an application
program and a printer. IBM 3270
Data Stream Capability (3270
DSC) is provided. Many devices
support both LU.T1 and LU.T3
print requests.
LU: See Logical Unit.
LU class: See Logical Unit
class.
LU-LU session: A connection
between two LUs.