User guide

Glossary
80 (87) EN/LZT1083982 R4
2000-12-07
Glossary
ADSL
Short for Asymmetric Digital Subscriber Line, a new technology that allows more data to
be sent over existing copper telephone lines (POTS). ADSL supports data rates of from
1.5 to 9 Mbps when receiving data (known as the downstream rate) and from 16 to 640
Kbps when sending data (known as the upstream rate). ADSL requires a special ADSL
modem.
ATM
Short for Asynchronous Transfer Mode, a network technology based on transferring data
cells or packets of a fixed size. The cell used with ATM is relatively small compared to
units used with older technologies. The small, constant cell size allows ATM equipment
to transmit video, audio and computer data over the same network, and ensures that no
single type of data hogs the line. ATM creates a fixed channel, or route, between two
points whenever data transfer begins. This differs from TCP/IP, in which messages are
divided into packets and each packet can take a different route from source to destination.
Authentication
The process of identifying an individual, usually based on a username and password.
Authentication merely ensures that the individual is who he or she claims to be, but says
nothing about the access rights of the individual.
Bandwidth
The amount of data that can be transmitted in a fixed amount of time. For digital devices,
the bandwidth is usually expressed in bits per second (bps) or bytes per second.
Bridge
A device that connects two local area networks (LANs), or two segments of the same
LAN. Unlike routers, bridges are protocol independent. They simply forward packets
without analyzing and rerouting messages.
CHAP
Short for Challenge Handshake Authentication Protocol, a type of authentication in which
the authentication agent (typically a network server) sends the client program a key to be
used to encrypt the username and password. This enables the username and password to
be transmitted in an encrypted form to protect them against eavesdroppers.
Configuration
The way a system is set up, or the assortment of components that make up the system.
Configuration can refer to either hardware or software, or the combination of both. When
you install a new device or program, you sometimes need to configure it, which means to
define values of parameters (for software).
Data Interface Connection
The link that provides the communication channel between two or more devices,
allowing them to pass data to one another.