Today, most organization's networks are based on personal computers. Individual users have their own desktop computers, which are connected to one or more
centralized computers, called network servers. A network server is usually a
powerful personal computer with special software and equipment
that enable it to function as the primary computer in the network.
PC-based networks and servers offer companies a great deal
of flexibility. For example, large organizations may have dozens
or hundreds of individual servers working together at the heart of
their network (see Fig. 1
Fig. 1: Network Servers
When set up in such groups—sometimes called clusters
or server farms
—network servers may
not even resemble standard PCs. For example, they may be
mounted in large racks or reduced to small units called “blades" which can he slid in and out of a case. In these large networks, different groups of servers may have different purposes, such as supporting a certain set of
users, handling printing tasks, enabling Internet communications, and so on.
Fig. 2: Workers connected to the Network Servers.
A PC-based server gives users flexibility to do different kinds of tasks (see Fig. 2
This is because PCs are general-purpose
machines, designed to be used in many ways.
For example, some users may rely on the
server for e-mail access, some may use it to
perform accounting tasks, and others may use
it to perform word-processing or Data Base Management jobs. The server can support
these processes, and many others, while
storing information and programs for many
people to use.
Depending on how the network is set
up, users may be able to access the server
in multiple ways. Of course, most users
have a standard desktop PC on their desk
that is permanently connected to the network. Mobile users, however, may be able
to connect a notebook PC or a handheld
device to the network by wireless means.
When they are away from the office, users
may be able to use the Internet as a means
of connecting to the company's network