1Lesson 1—Networking BASICS

Networking BASICS

Introduction to Networking

Unit 1

Lesson 1

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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.

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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.

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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.

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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.

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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.

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Network Communications

• Source

• Message

• Channel

• Receiver

• Noise

• Feedback

• Context

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Network Communications

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Types of Networks

• Two types of network classifications

Classified by device that controls network

Classified by distance between devices

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Types of Networks

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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.

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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.

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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.

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Wide Area Network

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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.

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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. Telecom-munications 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 actu-ally 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.

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Summary (continued)• The second type of network classified by the device that con-

trols the network is known as a server-based network. Unlike a peer-to-peer network, a server-based computer network is con-trolled by at least one special high-powered computer. These special computers are called servers, while the individual com-puters 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.

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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 thorough-fare, 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.