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Cisco 600 Series Installation and Operation Guide
78-11190-01
Glossary
C
CAP encoding
Carrierless Amplitude Phase signal modulation.
CO
Central office. Refers to equipment located at a Telco or service provider’s office.
CPE
Customer premises equipment. Refers to equipment located in a user's premises.
D
DMT
Discrete Multi-Tone frequency signal modulation.
downstream rate
The line rate for return messages or data transfers from the network machine to
the user’s customer premises machine.
DRAM
Dynamic Random Access Memory. A type of semiconductor memory in which
the information is stored in capacitors on a metal oxide semiconductor integrated
circuit.
DSLAM
Digital Subscriber Line Access Multiplexer. Concentrates and multiplexes
signals at the telephone service provider location to the broader wide area
network.
E
encapsulation
The technique used by layered protocols in which a layer adds header information
to the protocol data unit (PDU) from the layer above. As an example, in Internet
terminology, a packet would contain a header from the physical layer, followed
by a header from the network layer (IP), followed by a header from the transport
layer (TCP), followed by the application protocol data.
Ethernet
One of the most common local area network (LAN) wiring schemes, Ethernet has
a transmission rate of 10, 100, or 1000 Mbps.
