ADC CUDA 3 - Manual (Page 600)

ADC Telecommunications, Inc.
598 A PPENDIX C: G LOSSARY
Head-End The central location on the cable network that originates the broadcast video
and other signals in the downstream direction. See also Master Head-end,
Distribution Hub.
Header Protocol control information located at the beginning of a protocol data
unit.
HF See High Frequency.
HFC See Hybrid Fiber/Coaxial.
High Frequency
(HF) The entire subsplit (5-30 MHz) and extended subsplit (5-42 MHz) band used
in reverse channel communications over the cable television network.
High Return A frequency division scheme that allows bi-directional traffic on a single
coaxial cable. Reverse channel signals propagate to the head-end above the
downstream passband.
HRC See Harmonic Related Carrier.
Hum Modulation Undesired modulation of the television visual carrier by the fundamental or
low-order harmonics of the power supply frequency, or other low-frequency
disturbances.
Hybrid
Fiber/Coaxial
(HFC) System A broadband bidirectional shared-media transmission system using fiber
trunks between the head-end and the fiber nodes, and coaxial distribution
from the fiber nodes to the customer locations.
Hybrid
Fiber/Coaxial
(HFC) Network A network where the trunk of the cable plant is fiber technology. The fiber is
connected to a coaxial cable and the signal is converted so that it is
compatible to that media. The coaxial cable runs through the branches of
the network and is dropped into the subscriber’s home.
ICMP See Internet Control Message Protocol.
IEEE See Institute of Electrical and Electronic Engineers.
IETF See Internet Engineering Task Force.
IGMP See Internet Group Management Protocol.
Impulse Noise Noise characterized by non-overlapping transient disturbances.