Network
A
network is a connection of two or more computers that are to share resources
such as hardware, data, and software.
Benefits of a Network
Centralized storage of files is often the initial and
primary justification for a network. Instead of having multiple iterations of
documents and spreadsheets on disparate computers, files can be stored in a
centralized location. This then allows another benefit of networking,
centralized backup. With a centralized backup system, an organization’s files
can be backed up daily onto high capacity tapes. This helps ensure the long
term integrity of the data.
A more recently developed benefit of networks with the
advent of the Internet is the remote access of email and files. Using
technology known as Virtual Private Networking (VPN), an organization can
access its network remotely via a secure, encrypted channel by means of either
a dialup or Internet connection.
Components of a Network
Each computer on the network must have a Network
Interface Card (NIC). A NIC is the computer’s gateway to the network. The NIC
attaches to the network via connection medium, usually a wire or cable, which
attaches to the other computer. When there are more than two computers, their
cables can connect to a hub. A hub is like the center of a tire with spokes
emanating from it, each connecting to a separate computer or peripheral device.
Hubs come in various sizes, defined by the number of ports or connections they
offer. A switch is like an intelligent hub. A hub will broadcast a computer’s
request to every device on the network, while a switch will direct the request
directly to the recipient’s port. This helps relieve excess congestion and
improve performance on the network.
Most networks also have one or more central computers
called servers. A server is a powerful version of a desktop computer. They are
designed to be the managers of the network, performing such functions as file,
print and email servers.
Classification of
Networks
Networks are classified according to their
geographical coverage and size. The two most common network classifications are
local area networks (LANs) and wide area networks (WANs).
LANs
A LAN is a data network that is restricted
to a single geographical location and typically encompasses a relatively small
area such as an office building or school. The function of the LAN is to
interconnect workstation computers for the purposes of sharing files and
resources. Because of its localized nature, the LAN is typically high speed and
cheaper to set up than a WAN.