User`s guide

Glossary

All 1s

ÑAll Ones simulates the highest spectral components and highest energy

out of the product and out of the line repeaters on the E1 line.

All 0sÑA pattern that checks the correct operation of the HDB3 (E1) line cod-

ing. This code is meant to allow a pattern with many 0 bits to go through the

line transparently.

attenuationÑReduction or loss of signal strength, measured in decibels;

opposite of gain.

bandwidth

ÑThe data-carrying capacity of a transmission medium, usually

measured in Hertz (Hz), which equals cycles per second.

bipolarÑThe predominant signaling method used for digital transmission

services, such as

DDS and T1, in which the signal carrying the binary value

successively alternates between positive and negative polarities. Zero and

one values are represented by the signal amplitude at either polarity, while no

value ÒspacesÓ are at zero amplitude.

bit errorÑOccurs when the value of an encoded bit is changed in transmis-

sion, and interpreted incorrectly by the receiver.

broadbandÑServices or interfaces that operate above the T1 data rate, typi-

cally at

NxT1, T3, SONET, or ATM speeds.

central ofÞce (CO)

ÑThe phone company switching facility or center; usually

a Class

5 end ofÞce, at which subscribers' local loops terminate.

channelÑA physical or logical path allowing the transmission of informa-

tion; the path connecting a data source and receiver.