??? Clearly the computer and the application
of computing technology have had a significant impact on the lives of people. One of the technologies that has
benefited from computing technology is communications. Today we take for granted the fact that almost all of
the computing devices that we own are often connected together, exchange information, and function cooperatively
to make our lives easier.
A computer network is a group of computers that use common protocols to exchange information and share
resources. The computers in a network communicate in a variety of ways. Some of the computers may communicate
using electromagnetic signals transmitted over traditional copper wires or light being sent through fiberoptic
cables. Others may communicate using radio, satellite, or microwaves. Two computers can communicate even
if they are not directly connected. They can utilize a third computer to relay information.
In the context of a computer network, a protocol is a formal description of the message formats and the
rules the machines in the network follow to exchange messages. Think about using a telephone to communicate
with a friend. There are two aspects to the call: establishing the connection that makes it possible to talk, and
the rules, or the protocol, you use once the connection is established.
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