Usrobotics V.34 Manuel d'utilisateur télécharger pdf (Page 215)

COURIER HIGH SPEED MODEMS

J-6 Glossary

Dedicated Line

A user-installed telephone line used to connect a specified num-

ber of computers or terminals within a limited area, for

example, one building. The line is a cable rather than a public-

access telephone line. The communications channel may also be

referred to as nonswitched because calls do not go through

telephone company switching equipment.

Default

Any setting assumed, at startup or reset, by the computer's soft-

ware and attached devices, and operational until changed by

the user.

Digital Loopback

A test that checks the modem's RS-232 interface and the cable

that connects the terminal or computer and the modem. The

modem receives data (in the form of digital signals) from the

computer or terminal, and immediately returns the data to the

screen for verification.

Digital Signals

Discrete, uniform signals. In this manual, the term refers to the

binary digits 0 and 1.

Duplex

Indicates a communications channel capable of carrying signals

in both directions. See Half Duplex, Full Duplex.

EIA

Electronic Industries Association, which defines electronic stan-

dards in the U.S.

Equalization

A compensation circuit designed into modems to counteract

certain distortions introduced by the telephone channel. Two

types are used: fixed (compromise) equalizers and those that

adapt to channel conditions. U.S. Robotics high speed modems

use adaptive equalization.

1 2 ... 210 211 212 213 214 215 216 217 218 219 220 ... 244 245

Pas de commentaire

Usrobotics V.34 Manuel d'utilisateur Page 215