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Networking BASICS
Introduction to
Networking
Unit 1
Lesson 1
Lesson 1—Networking BASICS
1
Objectives
• Define a computer network.
• List the four purposes of a network.
• Explain the elements of
communication.
• List and describe the two types of
networks.
Lesson 1—Networking BASICS
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What Is a Net?
• A net is made up of individual pieces of rope
woven together.
• Single pieces of rope cannot trap an object.
• Woven-together pieces form a net that can
ensnare objects.
• The strength of a net comes from the pieces
being connected together.
• “The sum is greater than the parts.”
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What Is a Network?
• A network is anything that resembles a
net.
• Examples include a network of
politicians or a network of roads.
• Like a net, a network accomplishes
more through being connected together.
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What Is a Computer Network?
• A computer network is computers and
devices connected together.
• A single computer is limited to its own
hardware and software.
• The capabilities of a computer are
increased when connected with other
devices to form a computer network.
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Purpose of a Computer Network
• Summarized in a single word: sharing.
• Individual computers are isolated.
• Networked computers can share
resources.
• Three types of resources can be
shared.
• Networks also make computer
management easier.
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Share Software and Data
• Application and utility software can be
shared by all users across the network.
• This requires only a single software
copy to be purchased and maintained.
• Data files can also be shared.
• This makes data more accessible and
maintains integrity.
Lesson 1—Networking BASICS
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Share Hardware
• Sharing is an essential feature of a
computer network.
• This reduces costs and the work of
support staff.
• Printers, fax modems, scanners,
hard drives, CD-ROMs, and DVDs
can all be shared.
Lesson 1—Networking BASICS
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Improve Communications
• Communication is essential in today’s
businesses.
• Computer networks can help in
improved communications through
groupware.
• E-mail, electronic calendars,
collaborative writing, and video
conferencing are available.
Lesson 1—Networking BASICS
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Centralize Management
• Support staffs are stretched to the limits.
• Computer networks allow computers to be
managed from one central location.
• Software updates can be “pushed” to users’
computers.
• Problems can be diagnosed over the
network.
• Training can be done over the network.
Lesson 1—Networking BASICS
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Network Communications
•
•
•
•
Source
Message
Channel
Receiver
• Noise
• Feedback
• Context
Lesson 1—Networking BASICS
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Network Communications
Lesson 1—Networking BASICS
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Types of Networks
• Two types of network classifications
Classified by device that controls
network
Classified by distance between devices
Lesson 1—Networking BASICS
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Types of Networks
Lesson 1—Networking BASICS
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Peer-to-Peer Network
• No single computer controls
the network.
• Each computer is the same
(a peer) to all others.
• It is suitable for small offices.
Lesson 1—Networking BASICS
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Server-Based Network
• The network is controlled by a special
high-powered server.
• The server is dedicated to running the
network.
• Print and file servers, application
servers, communication servers, and
directory service servers are common.
Lesson 1—Networking BASICS
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Server-Based Network
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Local Area Network
• Network computers are located
relatively close to each other.
• They are generally limited to buildings
owned by one organization.
• They operate at high speeds.
• They are low-cost networks.
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Local Area Network
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Wide Area Network
• Network computers are spread out over
a larger area.
• They generally cross public
thoroughfares.
• They are often managed by public
carriers.
• They operate at lower speeds.
• They are a higher-cost network.
Lesson 1—Networking BASICS
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Wide Area Network
Lesson 1—Networking BASICS
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Summary
• A computer network is defined as multiple computers and
devices that are all connected together. By connecting the
computers together, the capabilities of each computer are
increased so the users can accomplish more.
• The purpose of a computer network is to share. Application
software, utility software, and the data that serves as input into
the software can all be shared across a network. Computer
hardware can also be shared on a computer network. Printers,
fax machines, scanners, modems, hard disk drives, CD-ROM
drives, and DVD drives are just a few of the hardware devices
that can be shared across a computer network.
Lesson 1—Networking BASICS
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Summary (continued)
• Computer networks can be important tools that help improve
communication between users. A special category of software
that assists with communication over a computer network is
known as groupware. Groupware refers to programs that help
people work together collectively even if they are located
remotely from each other. One of the most common groupware
applications used across computer networks is electronic mail,
or e-mail. Groupware services also include electronic calendars,
collaborative writing software, and video conferencing.
• The communication that takes place between devices on a
computer network is known as telecommunications. Telecommunications is defined as transmitting information over a
distance and is generally considered to be a two-way
transmission of voice, video, or data.
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Summary (continued)
• Computer networks allow the computers connected to the
network to be managed from one central location. Software
updates can be “pushed” across the network to all computers,
thus eliminating the need for support staff to visit every office
and perform the new installation. Problem diagnosis can be
performed across the network. Centralized management can be
used for training as well.
• Computer networks are generally classified two different ways.
The first classification of networks involves the device that actually controls the network. In a peer-to-peer network, no single
high-powered computer controls and manages the network. The
computers collectively run the network instead of a special
dedicated computer doing it. These networks are suitable for
small offices that need to share a printer or computer data.
Lesson 1—Networking BASICS
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Summary (continued)
• The second type of network classified by the device that controls the network is known as a server-based network. Unlike a
peer-to-peer network, a server-based computer network is controlled by at least one special high-powered computer. These
special computers are called servers, while the individual computers on the network are called clients. Servers are usually
dedicated to running the network and do not function as clients.
Instead, their sole job is to service requests quickly from the
network clients and ensure the security of the software and
hardware. There are many different types of specialized servers.
Lesson 1—Networking BASICS
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Summary (continued)
• Networks can also be classified by geography or how close the
devices are to each other. There are two categories of networks
based on geography. The first is a local area network (LAN). A
LAN is a computer network that has all the computers relatively
close to each other. They operate at high speeds for a low cost.
A wide area network (WAN) transmits over a public thoroughfare, such as a road, highway, railroad, or body of water. A WAN
service must be purchased from a carrier. WANs are managed
by the carrier instead of by the user. Compared to LANs, the
cost of WANs is high and they operate at a low speed.
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