Microsoft Office Tutorials and References
In Depth Information
Data Communications
Look at the computer advertised in Figure 1. Does this computer include any of the
ports illustrated in Figure 24? It mentions PS/2, USB, and parallel ports. Ports for a moni-
tor, mouse, and keyboard are also included, because the advertisement lists those devices.
One of the most important types of data communications in the business world is a net-
work connection. A network connects one computer to other computers and peripheral
devices, enabling you to share data and resources with your coworkers. There are a vari-
ety of network configurations, too many to discuss thoroughly here. However, any type of
network has some basic characteristics and requirements that you should know.
In a local area network (LAN), computers and peripheral devices are located relatively
close to each other, generally in the same building. If you are using such a network, it is
useful to know three things: the location of the data, the type of network card in your com-
puter, and the communications software that manages protocols and network functions.
Some networks have one or more computers, called servers , that act as the central stor-
age location for programs and provide mass storage for most of the data used on the net-
work. A network with a server and computers dependent on the server is called a
client/server network . The dependent computers are the clients . These networks are
dependent on the server because it contains most of the data and software. When a net-
work does not have a server, all the computers essentially are equal, and programs and
data are distributed among them. This is called a peer-to-peer network .
Each computer that is part of the network must have a network interface card (NIC)
installed. This card creates a communications channel between the computer and the net-
work. A cable is used to connect the NIC port to the network. Wi-Fi (short for wireless
fidelity) refers to a high-frequency wireless local area network (WLAN) . Wi-Fi is used to
connect computers in a network by transmitting data through the air from an alternative to
a wired LAN. Wi-Fi can be especially useful in buildings with older wiring. Network
software is also essential, establishing the communications protocols that will be observed
on the network and controlling the “traffic flow” as data travels throughout the network.
A personal computer that is not connected to a network is called a standalone
computer . When it is connected to the network, it becomes a workstation . You have
already learned that a terminal has a keyboard and monitor used for input and output, but
it is not capable of processing on its own. A terminal is connected to a network that uses
mainframes as servers. Any device connected to the network is called a node . Figure 25
illustrates a typical network configuration.
Network nodes include workstations, printers, and servers
Figure 25
Your local workstation
Search JabSto ::

Custom Search