Glossary - ZyXEL Communications Prestige 645R User Manual

10BaseT The 10-Mbps baseband Ethernet specification that uses two pairs of twisted-pair cabling
(Category 3 or 5): one pair for transmitting data and the other for receiving data.
ADSL Asymmetrical Digital Subscriber Line is an asymmetrical technology, meaning that the
downstream data rate is much higher than the upstream data rate. ADSL operates in a
frequency range that is above the frequency range of voice services, so the two systems can
operate over the same cable.
ARP Address Resolution Protocol is a protocol for mapping an Internet Protocol address (IP
address) to a physical machine address that is recognized in the local network.
ATM Asynchronous Transfer Mode is a LAN and WAN networking technology that provides
high-speed transfer. ATM uses fixed size packets of information called cells. These cells can
be switched more quickly and efficiently than variable length packets because they are all
regular and predictable with no need for dealing with different sizes of packets.
Backbone A high-speed line or series of connections that forms a major pathway within a network.
Bandwidth This is the capacity on a link usually measured in bits-per-second (bps)
Bit (Binary Digit) -- A single digit number in base-2, in other words, either a 1 or a zero. The
smallest unit of computerized data.
Byte A set of bits that represent a single character. There are 8 bits in a Byte.
CDR Call Detail Record. This is a name used by telephone companies for call related information.
CHAP Challenge Handshake Authentication Protocol is an alternative protocol that avoids sending
passwords over the wire by using a challenge/response technique
Client A software program that is used to contact and obtain data from a Server software program
on another computer. Each Client program is designed to work with one or more specific
kinds of Server programs, and each Server requires a specific kind of Client. A Web Browser
is a specific kind of Client
crossover A cable that wires a pin to its opposite pin, for example, RX+ is wired to TX+. This cable
Ethernet connects two similar devices, for example, two data terminal equipment (DTE) or data
cable communications equipment (DCE) devices.
CSU/DSU Channel Service Unit/Data Service Unit. CSUs (channel service units) and DSUs (data
service units) are actually two separate devices, but they are used in conjunction and often
combined into the same box. The devices are part of the hardware you need to connect

Glossary

Prestige 645 ADSL Internet Access Router
Glossary
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