APPC Subsystem on MPE/XL Node Manager's Guide (30294-90007)

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host: A central computer that
provides services for other
computers and terminals
attached to it.
I
independent LU: An LU
capable of conducting multiple,
simultaneous (parallel) APPC
sessions with another
independent LU on a remote
system. An independent LU can
function as either a primary or
secondary LU. See dependent LU.
INIT-SELF: An SNA request to
the SSCP to initiate an LU-LU
session.
internal trace: A trace file,
created by the APPC subsystem,
that records subsystem internal
events and state changes.
intrinsic: A subprogram
provided by Hewlett-Packard to
perform common functions such
as opening files, opening
communicationslines,performing
subsystem-defined functions, or
transmitting data over a
communications line.
L
local TP: The TP running on the
local processor.
locally controlled session: An
APPCsession controlled by an LU
on the local system. Also called a
first speaker session. If a
transaction program on the local
system attempts to allocate a
conversation, a locally controlled
session will always be granted if
one is available. If a transaction
program on the remote system
wants to allocate a conversation
over a locally controlled session, it
must ask permission of the local
LU. The local LU may grant or
deny the request. The APPC
subsystem supports only locally
controlled sessions.
logical device (ldev): A disk
file, a set of disk files, or a
physical device. An HP 3000 ldev
is identified by a number or by a
device class name.
Logical Unit (LU): The SNA
entity through which application
data is transmitted within an
SNA network. Logical Units are
the ports through which end
users have access to the network
(see end user). They format
message units, display
information, and handle error
recovery. There can be multiple
LUs in an SNA node.
LU type: A Logical Unit type,
defined by SNA to perform a
particular type of communication.
LU-LU session: The logical
connection between two logical
devices in an SNA network.
LU 6.2: An SNA LU type that
defines the communication that
can take place between two
application programs on separate
processors. LU 6.2 includes