Glossary
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firewall
A security system that helps protect a network from
hacker attacks and other threats that originate outside
the network. A hardware fi rewall is a device at the
entrance to a network that has specifi c data-checking
settings and that helps protect all of the devices
connected to it. A software fi rewall resides on a single
computer, helping to protect that computer from
external threats.
firmware
Software information loaded in permanent memory on
a device.
gateway
See “router.”
hexadecimal
A numbering system that uses the digits 0-9 plus the
letters A-F. The WEP key for your Xbox Wireless Adapter
can be hexadecimal.
host name
The DNS name of a device on a network, a name such
as www.microsoft.com.
infrastructure
network
A wireless network in which devices connect to
each other throughan access point, or use a more
sophisticated intermediary such as a router. Contrast
with “ad hoc network.”
IP
Acronym for “Internet Protocol.” The set of rules that
describe how to send data between computers over
the Internet. More specifi cally, this protocol governs
the routing of data messages, which are transmitted in
smaller components called packets.
IP address
Acronym for “Internet Protocol” address. An IP address
is an assigned number used to identify a computer that
is connected to a network or the Internet through the
Transmission Control Protocol/Internet Protocol (TCP/
IP). An IP address consists of four numbers (each of
which can be no greater than 255) separated by periods,
such as 192.168.2.1.
ISP
Acronym for “Internet service provider.” A company that
provides access to the Internet.
Kbps
Abbreviation of “kilobits per second.” A measure of data
transfer speed through a modem or on a network.
LAN
Acronym for “local area network.” A group of computers
and other devices dispersed over a relatively limited
area (for example, a building) and connected by a
communications link that enables any device to interact
with any other on the network.
