для Cisco Headend System Release 2.7
Glossary
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FTP
File Transfer Protocol. A method used to exchange files between computers on a network or
the Internet using the TCP/IP protocol.
G
GQAM
gigabit quadrature amplitude modulation. A QAM that provides up to sixteen 6 MHz outputs
while occupying only one unit of rack space. See also QAM, MQAM.
H
HDTV
high-definition television. The high-resolution subset of the DTV system.
headend
The location of the network elements that processes the signal by receiving and preparing the
source signals and making them ready for the transport network. See also network elements.
hub
Physical locations designed to serve a specific number of subscribers, usually 50 to 15,000.
May be co-located with the headend or miles away from the headend. Hubs receive,
modulate, and boost the signal prior to sending it to the network of HFC nodes for
distribution to the subscriber. Hubs usually contain QPSK modulalators/demodulators that
establish the two-way communications with the DHCTs.
I
Internet Protocol
The standard protocol within TCP/IP that defines the basic unit of information passed across
an Internet connection by breaking down data messages into packets, routing and
transporting the packets over network connections, then reassembling the packets at their
destination.
IP
See Internet Protocol.
IP address
A 32-bit sequence of numbers used for routing IP data. Each IP address identifies a specific
component on a specific network. The address contains a network address identifier and a
host identifier.
IPG
Interactive Program Guide. Our name for the on-screen program guide provided by the
Explorer DHCT.