computer networks fundamentals
DESCRIPTION
Computer Networks Fundamentals. Morrison / Wells. Objectives. Describe a network. Explain the benefits of a network. Identify the risks of network computing. 2. 2. Vocabulary. biometric security measures cable modem client. client/server network communication channels - PowerPoint PPT PresentationTRANSCRIPT
Computer Networks Fundamentals
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Morrison / Wells
Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Objectives
O Describe a network.O Explain the benefits of a network.O Identify the risks of network computing.
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Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Vocabulary
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O biometric security measures
O cable modemO client
O client/server network
O communication channels
O digital subscriber line (DSL)
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Morrison / Wells CLB: A Comp Guide to IC3 3E
VocabularyO Describe the roles of clients and
servers on a network.O List and describe the types of
networks.O List and describe communications
media and hardware.O Describe network security.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Vocabulary
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O extranetO firewallO hackerO hub
O InternetO intranetO local area
network (LAN)O modem
Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Vocabulary (continued)
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O nodeO peer-to-peer
networkO proxy server
O Public Switched Telephone Network (PSTN)
O routerO server
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Morrison / Wells CLB: A Comp Guide to IC3 3E
IntroductionO Connecting computers through a
network, a group of two or more computers linked together, allows users to share software applications and to share hardware devices such as printers, scanners, and other hardware add-ons.
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Introduction
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O server operating system
O T-1 lineO wide area
network (WAN)
O WiMAX -Worldwide Interoperability for Microwave Access
O wireless Internet service provider
O (WISP)-wirelessISP
O wireless LAN (WLAN)
Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Use of networksO Companies and organizations use
networks to connect employees and subsidiaries nationally and even internationally.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Introducing Networks
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O The Public Switched Telephone Network (PSTN) supports telephone service and is the world’s collection of interconnected commercial and government-owned voice-oriented systems.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Network BenefitsO The biggest network of all is the
Internet. Network benefits include:O Information sharingO Collaborative environmentO Hardware sharingO Software sharingO Enhanced communications
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Information sharing
Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Client/Server NetworksO The term client/server network
describes a software architectural model relationship.
O In most instances, the client is a software program such as Internet Explorer. The server is hardware and can be one of many types of servers, such as a mail server, a database server, an FTP server, an application server, or a Web server.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Risks of Networked Computing
O As with any technology, disadvantages also exist. Disadvantages of networks include:O Individual loss of autonomyO Malicious codeO Network faultsO Setup and management costsO E-mail is not necessarily private
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Network OsO Server operating systems are high-
end programs designed to provide network control and include special functions for connecting computers and other devices into a network.
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Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Network TypesO Networks are divided into two main
types: local area networks (LANs) and wide area networks (WANs).
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Network Types (continued)
O Wide Area Networks:O A WAN covers a large geographical area and
can contain communication links across metropolitan, regional, or national boundaries.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Network Types (continued)
O Local Area Networks:
O Most LANs connect personal computers, workstations, and other devices such as printers and scanners in a limited geographical area.
17Wireless LAN
Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Network types include:
O Client/server network: Server manages resources
O Peer-to-peer network: All computers are equal
O Intranet: Used within an organizationO Extranet: Specific outside users can
accessO Internet: Global network allows
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Lesson 24
Morrison / Wells CLB: A Comp Guide to IC3 3E
Communication Hardware:
O Communication hardware devices facilitate the transmitting and receiving of data. Examples are:O Modem: Converts analog signals to digital and
vice versaO Cable modem: Uses coaxial cableO Digital subscriber line: Uses ordinary phone linesO T-1: Type of fiber-optic telephone lineO Wireless: Delivers fast connection speeds
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Network Security Issues
O Passwords are the most common form of restricting access to data.
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Establishing and maintaining computer security is necessary to keep hardware, software, and data safe from harm or destruction.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Network Security Issues (continued)
O Other security measures include:O Electronic identification cardsO Firewalls to protect companies’ networks from external networksO Antivirus softwareO A proxy server that acts as an intermediary between a user and
the Internet.
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Network Security Issues (continued)
O Planning for Security:O Companies must plan for security before it is
neededO Institute a selective hiring process.O Regularly back up data and store it off site.O Employ biometric security measures.
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Network Security
O Wireless networking is very common, but has many security issues and hackers have found it very easy to access wireless networks.
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SummaryIn this lesson, you learned:O A network is a group of two or
more computers linked together.
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SummaryO A telephone network is similar in
makeup to a computer network. The Public Switched Telephone Network (PSTN) supports telephone service, and it is the world’s largest collection of interconnected commercial and government-owned voice-oriented systems.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Summary (continued)O You can use a network for
information sharing, hardware sharing, software sharing, and as a collaborative environment.
O Networks are divided into two main types: local area networks and wide area networks.
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summaryO Local area networks (LANs) connect
personal computers, workstations, and other devices such as printers and scanners in a limited geographical area, such as an office building, a school, or a home.
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Morrison / Wells CLB: A Comp Guide to IC3 3E
Summary (continued)
O A wide area network (WAN) is made up of several connected local area networks.
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SummaryO In a client/server network, one or
more computers on the network act as a server. The server manages network resources. In a peer-to-peer network, all of the computers are equal.
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Summary (continued)O Data security is a risk with many
networks. Some risks to computers are natural causes, some are accidents, and others are intentional.
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SummaryO The best way to protect data is to
effectively control the access to it. Generally, this protection is the responsibility of the network administrators and security personnel.
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SummaryO If unauthorized persons gain access
to data, they may obtain valuable information or trade secrets. Hackers are people who break into computer systems to steal services and information.
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Summary (continued)O Transmission media can be either
physical or wireless.O A modem is a type of communication
device. A hub is a device that controls the incoming and forwarding of data. A router directs traffic on the Internet or on multiple connected networks.
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SummaryO No computer is designated as the
server. People on the network each determine what files on their computer they share with others on the network.
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