GLOSSARY D

10/100BASE-T

The Institute of Electrical and Electronic Engineers (IEEE) 802.3 specification for

 

Ethernet over thin coaxial cable.

AAL5

ATM Adaptation Layer 5.

ADSL

Asymmetric Digital Subscriber Line is a technology in which data is transferred from

 

the service provider to the subscriber at up to 7.552 Mbps, and transferred from

 

subscriber to service provider at up to 928 Kbps. ADSL is the implementation of the

 

physical layer for transmission of data.

ATM

Asynchronous Transfer Mode is a high bandwidth, low delay, connection-oriented,

 

packet-like switching and multiplexing technique that uses 53-byte fixed-size cells to

 

transmit voice, video and data over a network. ATM layers define how cells are

 

formatted and provides the transport of the fixed length cells between the modem

 

and the service provider (or endpoints of the virtual connection).

attenuation

The dissipation of the power of a transmitted signal as it travels over copper wire,

 

measured in decibels (dB).

BER

Bit Error Rate is a measure of transmission quality. The ratio of error bits to the total

 

number of bits transmitted.

bps

bit-per-second is the number of bits transferred during each second of data

 

transmission.

CBR

Constant Bit Rate is a Service Class for the modem. It provides constant bit rate data

 

with a timing relationship between the source and the destination. Also, a traffic class

 

that carries a guaranteed constant bandwidth. Best suited for applications that require

 

fixed bandwidth, such as uncompressed voice, video and circuit emulation. CBR is a

 

Quality of Service class defined by the ATM Forum for ATM networks.

cell

A fixed-length packet. Also, the unit of data transmission used in ATM. Each ATM cell

 

contains a fixed-size frame (53 bytes) consisting of a five-byte header and a 48-byte

 

payload.

Megabit Modem 400F User Manual

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