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10BaseT
16 QAM
64 QAM
256 QAM
bandwidth
bridge
broadband
broadcast
Cable Modem
Termination System
(CMTS)
coaxial cable (coax)
Unshielded, twisted pair cable with an RJ-45 connector used with an Ethernet
LAN. "10" indicates the speed: 10Mbps; "Base" means that it is baseband
technology; and "T" means that it is a twisted pair cable.
Modulation scheme used by a modem transmitter. QAM uses amplitude and
phase modulation to encode multiple bits of data in one signaling element, thus
achieving higher data transfer rates than amplitude or phase modulation alone.
16 QAM encodes four bits per symbol as one of sixteen amplitude and phase
combinations. 16 QAM refers to the number of discrete phase/amplitude states
that represent data bits.
A modulation scheme used by a cable modem receiver. 64 QAM uses
amplitude and phase modulation to encode multiple bits of data in one
signaling element. 64 QAM encodes 6 bits per symbol as one of 64 amplitude
and phase combinations.
A modulation scheme used by a cable modem receiver. 256 QAM uses
amplitude and phase modulation to encode multiple bits of data in one
signaling element. 256 QAM encodes 8 bits per symbol as one of 256 possible
amplitude and phase combinations.
The range of frequencies that can be passed over a channel.
A device used to connect two LANs that use similar LAN protocols. The
bridge acts as an address filter, picking up packets from one LAN that are
intended for a destination on another LAN and passing them on. The bridge
does not modify the contents of a packet and does not add anything to the
packet. The bridge operates at Layer 2 of the Open System Interconnect (OSI)
model.
Network technology that multiplexes multiple, independent network carriers
onto a single cable. The technology is used to carry voice, video, and data over
a cable.
Transmission to two or more devices at the same time, such as over network or
by satellite; protocol mechanism by which group and universal addressing is
supported.
A device located in the cable system headend that interfaces the hybrid
fiber/coaxial (HFC) network to local or remote Internet Protocol (IP) networks.
Motorola's CMTS (Cable Router) provides connections between IP hosts and
cable modems, and between the cable modems and the connected subscribers.
It also manages cable modem bandwidth.
Cable that consists of an inner conductor surrounded by insulation. An outer
conductor is wrapped around the insulation, which is typically covered by
plastic. Coaxial cable has large bandwidth and can support transmission over
long distances.
Glossary
Glossary-1
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