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D Glossary
802.11 A family of specifications for wireless LANs developed by a
working group of the IEEE. This in an Ethernet protocol, often
called Wi-Fi.
10BASE-T A designation for the type of wiring used by Ethernet networks
with a data rate of 10 Mbps. Also known as Category 3 (CAT 3)
wiring. See data rate, Ethernet.
100BASE-T A designation for the type of wiring used by Ethernet networks
with a data rate of 100 Mbps. Also known as Category 5 (CAT 5)
wiring. See data rate, Ethernet.
ADSL Asymmetric Digital Subscriber Line
The most commonly deployed "flavor" of DSL for home users is
asymmetrical DSL. The term asymmetrical refers to its unequal
data rates for downloading and uploading (the download rate is
higher than the upload rate). The asymmetrical rates benefit
home users because they typically download much more data
from the Internet than they upload.
analog An analog signal is a signal that has had its frequency modified
in some way, such as by amplifying its strength or varying its
frequency, in order to add information to the signal. The voice
component in DSL is an analog signal. See digital.
ATM Asynchronous Transfer Mode
A standard for high-speed transmission of data, text, voice, and
video, widely used within the Internet. ATM data rates range
from 45 Mbps to 2.5 Gbps. See data rate.
authenticate To verify a user’s identity, such as by prompting for a password.
binary The "base two" system of numbers, that uses only two digits, 0
and 1, to represent all numbers. In binary, the number 1 is
written as 1, 2 as 10, 3 as 11, 4 as 100, etc. Although expressed
as decimal numbers for convenience, IP addresses in actual use
are binary numbers; e.g., the IP address 209.191.4.240 is
11010001.10111111.00000100.11110000 in binary. See bit, IP
address, network mask.
DHCP Dynamic Host Configuration Protocol
DHCP automates address assignment and management. When
a computer connects to the LAN, DHCP assigns it an IP address
from a shared pool of IP addresses; after a specified time limit,
DHCP returns the address to the pool.
DHCP relay Dynamic Host Configuration Protocol relay
A DHCP relay is a computer that forwards DHCP data between
computers that request IP addresses and the DHCP server that
assigns the addresses. Each of the Mitel 1000’s interfaces can be
configured as a DHCP relay. See DHCP.
DHCP server Dynamic Host Configuration Protocol server
A DHCP server is a computer that is responsible for assigning IP
addresses to the computers on a LAN. See DHCP.
digital Of data, having a form based on discrete values expressed as
binary numbers (0's and 1's). The data component in DSL is a
digital signal. See analog.
DNS Domain Name System
The DNS maps domain names into IP addresses. DNS
information is distributed hierarchically throughout the Internet
among computers called DNS servers. For example,
www.yahoo.com is the domain name associated with IP address
216.115.108.243. When you start to access a web site, a DNS
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