Configuring Systems for Terminals, Printers, and Other Serial Devices (32022-90057)

Glossary
programmatic device
Glossary
260260
programmatic device A device operating under
control of a program running on a computer.
Programmatic devices can be used for input, output,
or both, depending on the device and how it is
opened by the controlling program.
protocol A set of rules that enables two or more
data processing entities to exchange information. In
networks, protocols are the rules that govern each
layer of network architecture. They define which
functions are to be performed and how messages are
to be exchanged.
PSN Packet-Switching Network. Any data
communication network in which data is
disassembled into packets at a source interface and
reassembled into a data stream at a destination
interface. A public PSN offers the service to any
paying customer.
PSS Packet-Switching System. The national public
PSN of the United Kingdom.
PVC Permanent Virtual Circuit. A permanent
logical association between two physically separate
DTEs that does not require call set-up or clearing
procedures.
PXP See Packet Exchange Protocol.
Q
Q bit Qualified bit. When set in DATA packets the Q
bit signifies that the packet's user data is a control
signal for the remote device, not a message for its
user.
QuickVal A software program that tests whether
Network Services are operating correctly between
nodes.
R
RDBA Remote Data Base Access. A network service
that allows users to access data bases on remote
nodes.
reachable network A network that can be
accessed (with additional internet hops possibly
required) by a particular gateway.
remote connect device An asynchronous device
that is indirectly connected to a DTC through a
modem and telephone hook-up or through a PAD.
remote node Any network node that is physically
separate from the node you are currently using or
referring to.
retransmission count (N2) The maximum
number of times a frame will be retransmitted
following the expiration of the Retransmission
Timer, T1.
retransmission timer (T1) The length of time that
a transmitter will wait for an acknowledgment from
a destination address before attempting to
retransmit a frame. When choosing this value,
factors like the line speed and maximum frame size
should be taken into account.
RFA Remote File Access. A network service that
allows users to access file and devices on remote
nodes.
routing The path that packets or fragments of a
message take through a network to reach a
destination node.
RMP Remote Maintenance Protocol. HP proprietary
protocol used in DTC management.
RPM Remote Process Management. A network
service that allows a process to programmatically
initiate and terminate other processes throughout a
network from any node on the network.
RS-232-C The Electronic Industries Association
(EIA) Level 1 protocol specification that defines
electrical circuit functions for 25 connector pins. HP
provides two implementations of this standard: a
3-pin version for direct connections up to a distance
of 15 meters (50 feet), and a version which makes
use of additional circuits and can be used for either
modem or direct connections.
RS-422 The Electronic Industries Association (EIA)
Level 1 protocol specification implemented by HP in
a 5-pin version which can be used for direct device
connection up to a distance of 1500 meters
(4000 feet).