Multi Tech Equipment MTA128ST - Manual (Page 59)

Glossary
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telematics —User-oriented ISDN information transfer
services (e.g., teletex, videotex, facsimile).
Teleservices —A telecommunications service that
provides the complete capability for communication
between subscribers according to protocols agreed to
by RPOAs. A set of ISDN features using
communications links, including E-Mail and fax
services.
Teletext —A telecommunications service that provides a
one-way information retrieval service that uses
unused portions of a TV channel bandwidth. A fixed
number of text pages are repetitively broadcast for
decoding by a decoder at the TV set that can select
and display pages. See also ISDN.
terminal —The screen and keyboard device used in a
mainframe environment for interactive data entry.
Terminals have no box, which is to say they have no
file storage or processing capabilities.
terminal adapter (TA)—An ISDN DTE device for
connecting a non-ISDN terminal device to the ISDN
network. Similar to a protocol converter or an
interface converter, a TA connects a nonISDN device
between the R and S interfaces.
tone dialing
—One of two methods of dialing a
telephone, usually associated with Touch-Tone®
(push button) phones. Compare with pulse dialing.
TSR (terminate and stay resident)—A software
program that remains active and in memory after its
user interface is closed. Similar to a daemon in UNIX
environments.
twisted pair wiring —A type of cabling with one or
more pairs of insulated wires wrapped around each
other. An inexpensive wiring method used for LAN and
telephone applications, also called UTP wiring.
U
U reference point
—A twisted-pair subscriber loop
that connects the LT to the NT1. Normally a 2-wire
BRI or PRI line is used, but a 4- wire BRI can also be
used. In the US, the U Reference Point marks the
separation point between CPE and the network.
UART (universal asynchronous
receiver/transmitter)—An integrated circuit that
transmits and receives data on the serial port. It
converts parallel bytes into serial bytes for
transmission, and vice versa, and generates and
strips the start and stop bits appended to each
character.
UTP (unshielded twisted pair) —Telephone-type
wiring.
V
V.110
—One of the terminal rate adaptation protocols
for the ISDN B-channel. V. 110 is more hardware-
intensive than the V.120 B-channel standard.
V.120 —One of the terminal rate adaptation protocols
for the ISDN B-channel. V.120 is more software-
intensive than the V. 110 B-channel standard.
Videotex —A two-way information-retrieval service
that can be accessed by terminals and by a TV set
(with installed decoder). Allows interactive retrieval
of information pages from a central resource. See also
ISDN.
virtual circuit —A logical connection. Used in packet
switching wherin a logical connection is established
between two devices at the start of transmission. All
information packets follow the same route and arrive in
sequence (but do not necessarily carry a complete address).
x
X.25
—ITU-T’s definition of a three-level packet-switching
protocol to be used between packet-mode DTEs and network
DCEs. X.25 corresponds with layer 3 of the 7-layer OSI
model.
X.75 —An ITU-T standard for linking X.25 packet-switched
networks. X.75 defines the connection between public
networks, i.e., for a gateway between X.25 networks.