2014 BRG PDF (lo-res) - Blonder Tongue Laboratories Inc.

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Basic Glossary of CATV & IPTV Terms
subnet mask, and subnetwork.
Subnet Mask: A representation of a user's Internet
address where all of the bit positions corresponding to
the user's network and subnetwork id are 1's and the bit
corresponding to the user's host id are 0's.
Super-Band: The radio spectrum between 216 and approx.
400 MHz.
Switch: A switch is a device that forwards packets between
nodes based on the packet's destination node address
(either hardware or protocol).
T
Tap, Subscriber: A device that diverts a predetermined
amount of its input energy to one or more tap outputs. The
remaining balance of the input energy is presented to a tap
output port for propagation farther out into the system.
Tap, optical: A device for extracting a portion of the optical
signal from a fiber.
Telnet : A Telnet program allows a user at a terminal or
PC to log in to a remote computer and run a program and
execute other Unix commands.
Termination: Resistive device at end of distribution line or
unused outputs of equipment to avoid reflections (ghost).
Thru-Line Loss: Insertion loss of a tapoff.
Transmitter-Fiber: In a fiber optic system, the device
which converts a modulated electrical signal into an optical
signal for transmission through a fiber. A transmitter
typically consists of a light source (LED or diode laser) and
driving electronics.
Transmitter: A device that launches signals into a
communications network, to be collected by a receiver
on the other end.
Transcoder: Also Transmodulator. Changing a signal’s
modulation scheme to a different modulation for bandwidth
efficiency or system requirements.
Transponder: A frequency converter (translator) aboard a
satellite that changes the uplink signal to the downlink signal
and provides amplifications. Typical C-Band domestic
satellites have 24 transponders.
Transport Protocol: The Protocol Layer of the OSI 7-Layer
Model that is concerned with management of the data
flow between source and destination.
Trap: A device used to attenuate specific frequencies
of channels.
Trap: In SNMP, a message sent from the Agent to the
Console when the Agent detects that condition defined by
the network manager has occurred.
Two-way: Describing a transmission system, which can
transport signals in both directions simultaneously.
T-1 Carrier System: A digital transport signal (1.5 Mbps).
A 24-channel, transistorized, time-division, pulse-code
modulation, voice carrier used on exchange cable to provide
short-haul trunks.
U
UDP: A protocol within the TCP/IP protocol suite that
is used in place of TCP when a reliable delivery is not
required. There is less processing of UDP packets than
there is for TCP. UDP is widely used for streaming audio
and video, voice over IP (VoIP) and videoconferencing,
because there is no time to retransmit erroneous or
dropped packets.
Uplink: Transmission from earth to a satellite.
V
Vestigial Side Band (VSB): In amplitude-modulated transmissions,
a portion of only one sideband of a modulated
carrier. The modulated carrier is passed through a filter
having a graduated cut-off characteristic near the carrier
frequency.
Video: 1. Pertaining to the signal which carries a television
picture. 2. Describing the 4 MHz band of frequencies which
constitutes a television signal.
W
Watt: The Unit of Electric Power.
Waveguide: Any device which guides electromagnetic
waves along a path defined by the physical construction
of the device.
Wavelength Division Multiplexing (WDM): The provision
of two or more channels over a common optical
waveguide, the channels being differentiated by optical
wavelength.
8VSB: The 8-level vestigial sideband modulation method
adopted for terrestrial broadcast of the ATSC digital television
standard in the United States, Canada, and other
countries.