A computer network can consist of two computers
and up to a very high number of computers that are connected by some sort of
transmission media. This media can be with different sorts of wires or wireless.
A network can be small e.g. a group of computers in one room or office and up
to a widely distributed area e.g. throughout the world.
In a computer network multiple users can
share data and devices from one computer to another. Data and devices would
in this aspect be called a network's resources.
A network can be controlled and managed
from a computer in one central location. That is to say that from one computer,
another computer and its resources can be controlled and managed no matter where
in the world it is located. In this case the computer that the person would
be working on is called the local computer and the other computer that is accessed
by the person is called the remote computer.
The most basic type of a network is the
peer-to-peer. Here computers communicate and share resources directly on one
segment of cable and each computer can use another's resources. This makes it
insecure as data to be used only by authorized users is less protective. In
a peer-to-peer environment usually only a few computers are connected since
resources are not stored in one location. And when the peer-to-peer is established
adding additional devices might be very difficult. The advantage of having this
type of network is that its easy to setup and is less expensive than other types
of networks. This type resembles a simple LAN (Local Area Network) which is
setup usually in small spaces e.g. in one building or even one room. There are
more complex LANs which would be server based. This means the network relies
on one central computer to manage the network's resources. This network is referred
to as the client/server network.
Other types of networks: CAN (Campus Area
Network) which is generally connects e.g. two office buildings. MAN (Metropolitan
Area Network) which connects several office building in e.g. a city's CBD and
generally in a limited geographical area. WAN (Wide Area Network) which connects
two or more LANs in a wide geographical area e.g. multiple cities, countries
and generally around the world. The Internet is the best known WAN.
A network's services are file and print
services, communications services, mail services, Internet services, management
services.