Multitech CommPlete MT5634HD8, User Manual, Page: 87 / 99

Glossary
CommPlete Communications Server 81
Node : Any point within a network which has
been assigned an address.
Normal mode : In modem operation, this refers
to a mode of operation without error correction
active.
O
OCR (Optical Character Recognition) : The
recognition of printed characters and subsequent
translation into character code for use on a
computer. OCR systems can recognize many
different fonts, as well as typewriter and
computer-printed characters. Advanced OCR
systems can recognize hand printing.
Off-hook : The condition of a device which has
accessed a phone line (with or without using
the line). In modem use, this is equivalent to a
telephone handset being picked up. Dialing
and transmission are allowed, but incoming
calls are not answered.
OS (Operating System): The master control
program that runs a computing system. It is the
first program loaded when the computer is
turned on, and its main part is called the kernel
and resides in the memory at all times.
P
Parameter :
1. A “place holder” in a command which
should be substituted with useful
information.
2. The list of acceptable values for a given
option or command.
Parity bit : An extra bit attached to each byte of
synchronous data used to detect errors in
transmission.
PCB (Printed Circuit Board) : A flat board
that holds chips and other electronic
components. The board is “printed” with
electrically conductive pathways between
components. The main PCB in a system is called
a motherboard and the smaller PCBs that plug
into the slots in the motherboard are called
daughter boards or cards.
PCMCIA (Personal Computer Memory Card
International Association)
: An organization of
U.S. and Japanese companies set up to
standardize memory cards and other
architecture-independent expansion devices.
These cards are typically used in laptop
computers.
Phase : The timing of a signal based upon the
starting point of each cycle in another signal.
To be detected, phase requires the comparing of
two signals. If the cycle of two signals begin at
the same point, they are said to be “in-phase”.
In-phase signals add, while out-of-phase
signals tend to cancel each other.
Port : A location for input or output data
exchange. Computers, muxes, etc., have ports
for various purposes.
Print Server : A computer in a network that
controls one or more printers. It stores the print
image output from all users of the system and
feeds it to the printer one job at a time. The
print server may be part of the network
operating system or an add-on utility.
Program : A collection of computer instructions
that tell the computer what to do.
PROM (Programmable Read Only Memory):
A permanent memory chip that can be
programmed or filled by the customer after the
manufacturer has set initial values. Contrast
with ROM.
Prompt : A request for information from the PC
that provides required input or information.
Protocol : A set of rules that defines how
computing devices communicate with each
other. The rules governing the transmitting and
receiving of data.
PSK (Phase Shift Keying) : A modulation
technique which establishes two-bit elements,
called “dibits” yielding four possible
combinations: 00,01,10,11. These element are
then represented by 90, 180 and 270 degree
angles. PSK produces the appropriate shift in
phase relative to the original carrier.
Differential PSK replaces this technology
because it is less prone to error. Modems using
PSK normally operate at 1200 bps.
PSTN (Public Switched Telephone
Network)
: A worldwide public voice telephone
network that is used as a telecommunications
medium for the transmission of voice, data and
other information.
Pulse dialing : One of two methods of dialing a
telephone, usually associated with rotary dial
phones. Compare with tone dialing.