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the network. TCP is known as a "connection oriented" protocol due to requir-
ing the receiver of a packet to return an acknowledgment of receipt to the
sender of the packet resulting in transmission control.
TCP/IP
(
T
ransmission
C
ontrol
P
rotocol/
I
nternet
P
rotocol) - The basic com-
munication language or set of protocols for communications over a network
(developed specifically for the Internet). TCP/IP defines a suite or group of
protocols and not only TCP and IP.
Topology
- A network's topology is a logical characterization of how the
devices on the network are connected and the distances between them. The
most common network devices include hubs, switches, routers, and gateways.
Most large networks contain several levels of interconnection, the most impor-
tant of which include edge connections, backbone connections, and wide-area
connections.
WEP
(
W
ired
E
quivalent
P
rivacy) - A data privacy mechanism based on a 64-
bit or 128-bit shared key algorithm, as described in the IEEE 802.11 standard.
WLAN
(
W
ireless
L
ocal
A
rea
N
etwork) - A group of computers and associat-
ed devices that communicate with each other wirelessly.
Workgroup
- Two or more individuals that share files and databases.
PC Card
- A credit-card sized removable module that contains memory, I/O,
or a hard disk.
Port
- A pathway into and out of the computer or a network device. For exam-
ple, the serial and parallel ports on a personal computer are external sockets for
plugging in communications lines, modems and printers.
RJ-45
(
R
egistered
J
ack-
45
) - A connector similar to a telephone connector that
holds up to eight wires, used for connecting Ethernet devices.
Roaming
- In an infrastructure mode wireless network, this refers to the abili-
ty to move out of one access point's range and into another and transparently
reassociate and reauthenticate to the new access point. This reassociation and
reauthentication should occur without user intervention and ideally without
interruption to network connectivity. A typical scenario would be a location
with multiple access points, where users can physically relocate from one area
to another and easily maintain connectivity.
Server
- Any computer whose function in a network is to provide user access
to files, printing, communications, and other services.
Software
- Instructions for the computer. A series of instructions that performs
a particular task is called a "program." The two major categories of software are
"system software" and "application software." System software is made up of
control programs such as the operating system and database management sys-
tem (DBMS). Application software is any program that processes data for the
user.
SSID
(
S
ervice
S
et
ID
entifier) - A unique name shared among all points in a
wireless network. The SSID must be identical for each point in the wireless net-
work and is case-sensitive.
Switch
- 1. A data switch connects computing devices to host computers,
allowing a large number of devices to share a limited number of ports. 2. A
device for making, breaking, or changing the connections in an electrical cir-
cuit.
TCP
(
T
ransmission Bontrol
P
rotocol) - A method (protocol) used along with
the IP (Internet Protocol) to send data in the form of message units (datagram)
between network devices. While IP takes care of handling the actual delivery
of the data (routing), TCP takes care of keeping track of the individual units of
data (called packets) that a message is divided into for efficient delivery over
