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

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programmable and
nonprogrammable
communication controllers.
Hewlett-Packard's INP and PSI
are types of communications
controllers.
communications link: The
hardware that directly connects
two locations for the purpose of
data transfer, including the
interface boards, cables, and
modems (if a telephone line is
used).
Control Unit (CU): A device
that controls input and output for
one or more devices such as
printers or display stations.
CU: See Control Unit.
D
data set: In IBM terminology,
any file.
E
emulation: A technique, using
software, allowing one computer
to behave exactly like another
computer. An HP emulation of an
IBM device is a Hewlett-Packard
data communications product
that enables an HP computer or
terminal to carry out many of the
functions of the IBM device. For
example, the Hewlett-Packard
SNA IMF product enables an HP
computer to carry out many of the
functions of an IBM 3270 device.
F
FMD: See Function
Management Data services.
FMH: See Function
Management Header.
front end processor: A smaller
computer that relieves a larger
host computer of certain
processing tasks, such as error
detection, line control, and
message handling.
Function Management Data
(FMD) services: A generic term
that describes two SNA layers:
Session Presentation and Session
Network Services.
Function Management
Header (FMH): An SNA header
that selects a destination or
source for subsequent data
transmission and supplies
information for other data
management tasks.
H
host: A central computer that
provides services for other
computers and terminals
attached to it.
I
INIT-SELF: An SNA request to
the SSCP to initiate an LU-LU
session.
intrinsic: A subprogram
provided by Hewlett-Packard
systems. Intrinsics perform
common functions such as