Communication and network

• The internet
• Network and network devices

Module 2

The Internet: Connecting and Communicating Online

The Internet Evolution (1 of 4)

• The web, originally known as the world wide web, is a service consisting of websites located on computers around the world, connected through the Internet.
• The internet is a global collection of millions of computers linked together to share information.
• Each of the networks on the Internet provides resources that add to the abundance of goods, services, and information accessible via the Internet.

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Figure 2-1 People around the world use the Internet

in daily activities such as viewing media, communicating

with others and accessing information.

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The Internet Evolution (2 of 4)

• The Internet has its roots in a networking project started by the Pentagon’s Advanced Research Projects Agency (ARPA), an agency of the U.S. Department of Defense. ARPA’s goal was to build a network that:

(1) enabled scientists in various physical locations to share information

(2) can function even if part of the network was disabled or destroyed by a disaster, such as a nuclear attack

• The original ARPANET consisted of four main computers, one each located at the University of California in Los Angeles, the University of California in Santa Barbara, the Stanford Research Institute, and the University of Utah. Each of these computers served as a host on the network.

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The Internet Evolution (3 of 4)

• Bandwidth is a common term used to describe the capacity of a communications channel.

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• Net neutrality is the concept that one website has the same value or priority as other websites, resulting in equal, unrestricted access to each site.

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• Internet service provider (ISP) is a company that sells Internet access who must provide the same level of service to all websites, regardless of content or purpose.

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The Internet Evolution (4 of 4)

Figure 2-2 ARPANET network map from 1974.

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Knowledge Check Activity 2-1

A company that provides services for accessing the Internet is called a(n) ________.

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1. Network service package
2. Network service seller
3. Internet service provider
4. Internet service seller

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Using the World Wide Web�(1 of 11)

• A web page is a specially formatted document that can contain text, graphics, sound, video, and links to other web pages. The content of most web pages is designed to make them visually appealing and easy to find.
• Web pages are either static or dynamic. When you visit a static web page, you see the same content each time.
• With a dynamic web page, by contrast, the content of the web page is regenerated each time you display it. Dynamic web pages may contain customized content, such as the current date and time of day, desired stock quotes, weather for a region, or ticket availability for flights.
• Hyperlinks, often shortened to links, are words or graphics you can click to display a web page or other resources on the Internet, such as a file.

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Using the World Wide Web�(2 of 11)

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Figure 2-3 Web page

Using the World Wide Web�(3 of 11)

• A collection of related webpages (often shortened to "pages”) and associated items, such as documents and photos, stored on a webserver makes up a website.
• A webserver is a computer that delivers requested webpages to your computer or mobile device. The same webserver can store multiple websites.
• Responsive web design adapts the layout of the website to fit the screen on which it is being displayed. HTML (Hypertext Markup Language) is a set of codes that developers use to specify the headings, paragraphs, images, links, and other content elements that a web page contains.
• HTML is one of the core technologies for developing web pages, along with CSS (cascading style sheets). HTML specifies a web page’s layout. CSS is used to specify the content’s design and appearance.

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Using the World Wide Web�(4 of 11)

Figure 2-4 HTML code.

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Using the World Wide Web�(5 of 11)

Table 2-1 Popular Browsers

Using the World Wide Web�(6 of 11)

• Websites often use cookies, which are small text files generated by a web server to store information, such as items you view or purchase on an e-commerce site.

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• The browser also keeps track of pages you have viewed in sequence by tracking breadcrumbs—the path you followed to display a web page.

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• The navigation bar in a browser includes buttons, such as Back and Forward, that you can use to revisit web pages along the breadcrumb path.

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Using the World Wide Web�(7 of 11)

• A browser displays the URL for the current web page in its address bar, the part of a browser window that displays the location of the current web page.

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Using the World Wide Web�(8 of 11)

Figure 2-6 Parts of a URL

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Using the World Wide Web�(9 of 11)

An IP address is a unique number that consists of four sets of numbers from 0 to 255 separated by periods, or dots, as in 69.32.132.255. The Internet uses two IP addressing schemes: IPv4 and IPv6.

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Figure 2-5 The IPv4 and IPv6 addresses, along with the domain name, for Google’s website.

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Using the World Wide Web�(11 of 11)

• The domain name system (DNS) is the method that the Internet uses to store domain names and their corresponding IP addresses.

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• When you enter a domain name (i.e., google.com) in a browser, a DNS server translates the domain name to its associated IP address so that the request can be routed to the correct computer.

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• A DNS server is a server on the Internet that usually is associated with an ISP.

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How To: Connect to the Internet (1 of 5)

• A hot spot is a wireless network device that provides Internet connections to mobile computers and devices.
• A mobile hot spot enables you to connect a phone, computer, or other device to the Internet through the cellular network.

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Figure 2-8 Verizon mobile hot spot

How To: Connect to the Internet (2 of 5)

• Various types of cellular networks, including 4G and 5G, are available.
• 4G (fourth generation) cellular networks can provide Internet services in most locations where cellular service is offered.
• 5G networks provide higher-speed data transmission, making them more appealing to those requiring access to high-bandwidth content.

How To: Connect to the Internet (3 of 5)

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Figure 2-9 How a cellular network might work.

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How To: Connect to the Internet (4 of 5)

• Wireless networks that are available in public places, such as hotels, restaurants, and coffee shops, are known as Wi-Fi networks.

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• Mobile hot spot: Many smartphones contain mobile hot spot functionality, although cellular service providers may charge an extra fee to use it, and any data transmitted or received through the hot spot will be added to your overall data usage.

FIGURE 2-10 Available wireless networks

How To Connect to the Internet (5 of 5)

• Tethering transforms a smartphone or Internet-capable tablet into a portable communications device that shares its Internet access with other computers and devices wirelessly.

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Figure 2-11 Netgear wireless access point

Various Online Activities and Services ( 1 of 6)

• Informational and research websites contain information. Examples include libraries, encyclopedias, dictionaries, directories, guides, and other types of references.
• Educational websites offer formal and informal teaching and learning
• Business websites aim to increase brand awareness, provides company background or other information, and/or promotes or sells products or services.

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• Government agency websites provide citizens with information such as census data, or assistance such as forms for filing taxes

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• A blog is an informal website consisting of time-stamped articles, or posts, in a diary or journal format, usually listed in reverse chronological order.

Various Online Activities and Services (2 of 6)

Figure 2-16: The U.S. Bureau website provides population data.

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Various Online Activities and Services (3 of 6)

• Health and fitness websites provide up-to-date medical, fitness, nutrition, or exercise information for public access.
• Science websites contain information about space exploration, astronomy, physics, earth sciences, microgravity, robotics, and other branches of science.
• Entertainment websites offer music, videos, shows, performances, events, sports, games, and more in an interactive and engaging environment.

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Various Online Activities and Services (4 of 6)

• Bookmarking site is a website that enables members to organize, tag, and share links to media and other online content.
• A tag is the descriptive text used to categorize media and invite comments. You can assign tags to web pages, photos, videos, blog posts, email messages, social media messages, and other digital content so that it is easier to locate later.
• Social media refers to the many ways individuals and businesses share information and interact using the Internet.

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Various Online Activities and Services (5 of 6)

• Online banking and online trading

enable users to access their financial

records from anywhere in the world,

provided they have an Internet

connection.

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Figure 2-18 You can manage your bank account, make transfers, and more with banking websites, such as Bank of America.

Various Online Activities and Services (6 of 6)

Pros and cons of using web apps.

Considerations for Online Safety (1 of 3)

• A secure website uses encryption to safeguard transmitted information.
• Encryption is a security method that scrambles or codes data as it is transmitted over a network so that it is not readable until it is decrypted.
• An encrypted website connection displays https instead of http in the URL.
• The “s” in https stands for “secure,” so https means Hypertext Transfer Protocol Secure.

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Considerations for Online Safety (1 of 2)

• Secure websites often use a digital certificate to verify a user’s identity with a digital key that has been “signed” by a trusted third party.

Figure 2-22 Digital certificates provide security when visiting websites.

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Considerations for Online Safety (2 of 3)

• ONLINE SAFETY TIPS
• Verify that the website is safe
• Turn off location sharing
• Clear your browsing history
• Never store passwords
• Use a phishing filter
• Enable a pop-up or pop-under blocker
• Use private browsing
• Use a proxy server

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Communicating Online (1 of 6)

• Email was one of the original services on the Internet, enabling scientists and researchers working on government-sponsored projects to communicate with colleagues at other locations.

Figure 2-24 You can send email to anyone, anywhere in the world.

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Communicating Online (2 of 6)

• Internet messaging services, which often occur in real time, are communications services that notify you when one or more of your established contacts are online and then allow you to exchange messages or files or join a private chat room with them.

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Figure 2-25 How an email message may travel from a sender to a receiver.

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Communicating Online (3 of 6)

• Most messaging apps include the following features, which allow for a variety of communication types:
• Text messaging
• Multimedia messaging
• Voice messaging
• Voice-to-text (also called speech-to-text)
• Online discussion

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Figure 2-26 Facebook Messenger is an example of messaging app.

Using Social Networks (4 of 6)

Types of social networks.

Using Social Networks (5 of 6)

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Types of social networks. (Continued)

Using Social Networks (6 of 6)

• Privacy and Security Risks with Online Social Networks
• Follow the tips to help protect yourself against thieves who are following the network traffic and attempting to invade private facets of your life.
• Register with caution
• Manage your profile
• Choose friends carefully
• Limit friends
• Divulge only relevant information
• Be leery of urgent requests for help

Information Literacy Standards�and Web Searches (1 of 3)

• Search engine uses programs called spiders or crawlers. A spider or crawler is software that combs the web to find web pages and add new data about them to the database, thereby building an index, or listing of terms and their locations.
• A query is a search term entered into a search engine on the web to obtain results.
• A search tool finds online information based on criteria you specify or selections you make.
• Another type of search tool is a web directory, or subject directory, which is an online guide to subjects or websites, usually arranged in alphabetical order.

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Information Literacy Standards�and Web Searches (2 of 3)

Figure 2-35 Steps in a search strategy

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Apply Information Literacy Standards�to Web Searches (3 of 3)

You can also refine a web search by using a search operator, also called a Boolean operator. Search operators are characters, words, or symbols that refine the search.

Below are the common search operators:

Using Online Content Responsibly and Ethically (1 of 3)

• On the Internet, anyone can publish anything to a website, a blog, or a social media site, regardless of whether the information is true.
• One way to evaluate a web page is to use the CARS checklist and determine whether the online information is credible, accurate, reasonable, and supportable.
• A citation is a formal reference to a source, such as a published work.

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Using Online Content Responsibly and Ethically (2 of 3)

• If you copy a photo from the Internet and use it in a report, you might be violating the photographer’s intellectual property rights, which are legal rights protecting those who create works such as photos, art, writing, inventions, and music.
• Some online resources, such as e-books, newspapers, magazines, and journals, are protected by digital rights management (DRM), which is a collection of technologies used by software publishers and trade groups to fight software piracy (theft) and prevent unauthorized copying of digital content; these include authentication, certificates of authenticity, encryption, and digital watermarks.

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Using Online Content Responsibly and Ethically (3 of 3)

• A public domain means it is not subject to copyright.
• Creative Commons is a nonprofit organization that helps content creators keep the copyright to their materials while allowing others to use, copy, or distribute their work.

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Ethics and Issues: Using Online Content�Responsibly (1 of 2)

• Ethics is the set of moral principles that govern people’s behavior.
• Ethically and legally, you can use other people’s ideas in your research papers and presentations, provided you cite the source for any information that is not common knowledge.
• Some software, such as Microsoft Word, helps you create and manage citations and then produce a bibliography, which is an alphabetical collection of citations.

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Ethics and Issues: Using Online Content�Responsibly (2 of 2)

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Figure 2-37 Citing sources in Microsoft Word

Module 9

Networks and Network Devices: Communicating and Connecting

How Do You Interact with a Network �(1 of 9)

• A Network is a system of two or more devices linked by wires, cables, or a telecommunications system.
• Networks allow computers to share resources, such as hardware, software, data, and information.
• A Network requires a combination of hardware and software to operate.
• Networks act as a communications system around the globe through the Internet.

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Figure 9-1 Networks can share resources and data

How Do You Interact with a Network �(2 of 9)

• The process in which two or more computers or devices transfer data, instructions, and information is known as digital communications.
• All types of computers and mobile devices serve as sending and receiving devices in a communications system.
• Communications devices are modems, wireless access points, routers, and so on.
• Transmission media can be wired or wireless.

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How Do You Interact with a Network �(3 of 9)

Table 9-1 Communication system components.

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How Do You Interact with a Network �(4 od 9)

How Do You Interact with a Network �(5 of 9)

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Figure 9-3 Typical home network.

How Do You Interact with a Network �(6 of 9)

Home Networks provide home users with the following capabilities:

• Multiple users can share a single Internet connection.
• Files on each computer, such as photos, can be shared.
• Multiple computers can share a single hardware resource, such as a printer.
• Game consoles can connect to the Internet to facilitate online gaming.

Business Networks provide the following advantages to businesses:

• Facilitate communication among employees
• Share hardware, such as printers and scanners
• Share data, information, and software with one another
• Centrally store and backup critical information

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How Do You Interact with a Network �(7 of 9)

Intranet

• An intranet (intra means within) is an internal network that uses Internet technologies.

Extranet

An extranet (extra means outside or beyond) allows customers or suppliers to access part of its intranet.

VPN

A VPN can allow an individual to access an organization’s network by using encryption and other technologies to secure the data transmitted along the path.

Businesses use intranets, extranets, and VPNs (virtual private networks) to provide different services to employees.

How Do You Interact with a Network �(8 of 9)

Wired Networks

• It sends signals and data through cables traveling through floors and walls to connect to other network devices.
• Wired networks tend to be more secure and transmit data faster than wireless networks.

Wireless Networks

• It sends signals through airwaves and usually does not require cables.
• Wireless networks can be less secure but more convenient and easier to set up than wired networks.

Cellular network or mobile network is a communication network where the link to and from end nodes is wireless.

• Various types of cellular networks are 3G, 4G, and 5G.

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How Do You Interact with a Network �(9 of 9)

Communications software consists of programs and apps that:

• Help users establish a connection to another computer, mobile device, or network
• Manage the transmission of data, instructions, and information
• Provide an interface for users to communicate with one another

Network Structures (1 of 7)

• Home and business networks describe the main users of a Network.
• Networks can be classified by:
• Their topology (the method by which computers and devices are physically arranged on a network)
• Network architecture (the logical design of all devices on a network)
• Geographic reach
• Topology describes the layout of network devices, architecture describes the role of servers and users, and the geographic span of a network determines how wide the network reaches.
• Common network topologies include bus network, ring network, star network, and mesh network.

Network Structures (2 of 7)

Table 9-2 Network topologies.

Network Structures (3 of 7)

Table 9-2 Network topologies (continued).

Network Structures (4 of 7)

• On a client/server network, one or more computers act as a server, and the other computers on the network request resources from the server.
• A client is a computer or mobile device on the network that relies on the server for its resources.
• Client/server networks are controlled by a network administrator.

Figure 9-5 Sample client/server network.

Network Structures (5 of 7)

• A peer-to-peer (P2P) network is a network architecture that connects a small number of computers, fewer than 10.
• With this type of network, computers communicate directly with one another and can share one another’s resources.
• All computers are treated equally, and a network administrator is not required.
• A type of P2P network where users share files over the Internet.
• The files in an Internet peer-to-peer network transfer directly from one user’s computer to the other.
• It is illegal to share copyright-protected files or other resources.

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Network Structures (6 of 7)

• A local area network (LAN) connects computers and devices in a limited area.

Figure 9-6 Sample LAN.

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Network Structures (7 of 7)

• Network configurations come in a variety of sizes, which can be determined not only by the number of devices they connect but also by their geographic reach.
• A wireless LAN (WLAN) is a LAN that uses wireless connections.
• A wide area network (WAN) is a network that connects devices in a large geographic region.
• A metropolitan area network (MAN) is a type of wide-area network that is operated by a city or county.
• A personal area network (PAN) connects personal digital devices connected via Bluetooth like a smartwatch.
• A body area network (BAN) is a form of personal area network that consists of small, lightweight biosensors implanted in the body.

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Network Standards and Protocols (1 of 11)

• Network standards define guidelines that specify the way computers access a network, the type(s) of hardware used, data transmission speeds, and the types of cable and wireless technology used.
• A protocol is a standard that outlines the characteristics of how devices communicate on a network, such as data format, coding schemes, error handling, and the sequence in which data transfers over the network.
• Network standards and protocols work together to move data through a network.
• The most common standard for wired networks is Ethernet. It controls how network interface cards (NICs), routers, and modems share access to cables and phone lines, as well as how they transmit data.
• Most businesses use a standard, such as EDI (electronic data interchange), that defines how business documents travel across transmission media.

Network Standards and Protocols (2 of 11)

Table 9-3 Network standards and protocols.

Network Standards and Protocols (3 of 11)

• A protocol may define data format, coding schemes, error handling, and the sequence in which data transfers over a network.
• One common family of protocols is TCP/IP (Transmission Control Protocol/Internet Protocol).
• TCP defines how data is routed through a network, and IP specifies that all computers and devices connected to a network have a unique IP address.
• Two types of IP addresses: IPv4 (Internet Protocol version 4) and IPv6 (Internet Protocol version 6).
• The network protocols for LANs, WANs, MANs, and other wireless protocols support close-distance communication.
• These standards include Wi-Fi, LTE, Bluetooth, UWB, IrDA, RFIC, and NFC.

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Network Standards and Protocols (4 of 11)

• Wireless capability of computers or devices to communicate via radio waves with other computers or devices using Wi-Fi, which identifies any network based on the 802.11 standards.
• 802.11 is a series of network standards developed by the IEEE.
• Common standards include 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax, with data transfer rates ranging from 11 Mbps to 7 Gbps.
• A designation of 802.11 ac/b/g/n/ac/ax on a computer, router, or other device indicates that it supports those six standards (ac, b, g, n, ac, and ax).
• Wi-Fi networks can easily be integrated with wired Ethernet networks.
• Extra hardware needs to be installed to extend or strengthen a wireless signal.

Network Standards and Protocols (5 of 11)

• Bluetooth is a network protocol that defines how two Bluetooth devices use short-range radio waves to transmit data.
• The data transfers between devices at a rate of up to 3 Mbps.
• A Bluetooth device contains a small chip that allows it to communicate with other Bluetooth devices.
• Two Bluetooth devices are connected initially using a code, and devices that share a Bluetooth connection are said to be paired.
• Connect devices with vehicle stereos to use the vehicle’s speakers to project sound
• Use GPS receivers to send directions to a mobile phone or GPS-enabled device
• Transfer photos wirelessly from a digital camera to a laptop or server. Replace wired communications devices, such as barcode readers, with wireless devices to enhance portability

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Network Standards and Protocols (6 of 11)

Figure 9-7 Connecting your phone to your car’s Bluetooth.

Network Standards and Protocols (7 of 11)

• UWB is a network standard that specifies how two UWB devices use short-range radio waves to communicate at high speeds with each other.
• UWB can transmit signals through doors and other obstacles.
• UWB is best suited for the transmission of large files, such as video, graphics, and audio.
• Examples of UWB uses include locating and tracking inventory, equipment, or personnel in remote or dangerous areas.
• Devices, such as television remote controls, use the IrDA (Infrared Data Association) standard to transmit data wirelessly to each other via infrared (IR) light waves.
• Since Bluetooth and UWB do not require line-of-sight transmission, these technologies are more widespread than IrDA.

Network Standards and Protocols (8 of 11)

• RFID (radio frequency identification) is a protocol that defines how a network uses radio signals to communicate with a tag placed in or attached to an object, an animal, or a person.
• The tag, called a transponder, consists of an antenna and a memory chip that contains the information to be transmitted.
• An RFID reader, also called a transceiver, reads the radio signals and transfers the information to a computer or other computing device.
• Readers can be handheld or embedded in an object, such as a doorway or a tollbooth.

Network Standards and Protocols (9 of 11)

Figure 9-8 How electronic RFID toll collection works.

Network Standards and Protocols (10 of 11)

• NFC (near-field communications) is a protocol based on RFID.
• Smartphones, digital cameras, televisions, and terminals are NFC-enabled devices.
• Credit cards, tickets, and NFC tags are examples of objects that also use NFC technology.
• An NFC tag is a chip that can store small amounts of data.
• NFC tags can be found in many different items, including business cards, wristbands, stickers, and ski lift tickets.

Figure 9-9 NFC communication examples.

Network Standards and Protocols (11 of 11)

Table 9-4 Close-distance network protocols.

Network Connection Hardware (1 of 8)

• Nodes, or devices on a network, can be computers, tablets, mobile phones, printers, game consoles, or smart home devices.
• Hubs provide a central point for network cables in a network and are used to transfer data to all devices.
• Switches, used more frequently than hubs, also provide a central point for network cables in a network and transfer data only to the intended recipient.
• Routers connect two or more networks and direct, or route, the flow of information along the networks.

Network Connection Hardware(2 of 8)

• A modem connects a sending or receiving device, such as a computer, to a communications channel, such as the Internet.
• The modem connects your network to the Internet through an ISP.
• A digital modem, also called a broadband modem, is a communications device that sends and receives data and information to and from a digital line.
• Three types of digital modems are cable modems, DSL modems, and ISDN modems.

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Network Connection Hardware (3 of 8)

Figure 9-10 Typical cable modem installation.

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A cable modem uses a cable TV connection. A splitter connects one part of the cable to your cable box or device, and the other part to the cable modem.

Network Connection Hardware (4 of 8)

• A DSL modem uses standard copper telephone wiring.
• An ISDN (Integrated Services Digital Network) modem is a broadband modem that sends digital data and information from a computer to an ISDN line and receives digital data and information from an ISDN line.
• DSL and ISDN modems are external devices.

Figure 9-11 Cable modem and

wireless router.

Network Connection Hardware (5 of 8)

• A dedicated line is a type of always-on physical connection that is established between two communications devices.
• Businesses often use dedicated lines to connect geographically distant offices.
• Dedicated lines can be either analog or digital.
• Multiplexing is a process that combines multiple analog or digital signals into a single signal over a shared medium, such as a cable.
• Digital dedicated lines include cable television lines, DSL, ISDN lines, FTTP, T-carrier lines, and ATM.

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Network Connection Hardware (6 of 8)

Table 9-5 Digital dedicated lines.

Network Connection Hardware (7 of 8)

Table 9-5 Digital dedicated lines (continued).

Network Connection Hardware (8 of 8)

Table 9-5 Digital dedicated lines (continued).

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How To: Set Up a Network (1 of 5)

• A home network can be as simple as using a cable to connect two devices.
• A wireless, Internet-connected home network requires hardware like:
• a modem
• a router
• a wireless access point
• devices to be connected
• Installation of a home wireless network depends on factors such as:
• the type of wireless network hardware you purchase
• the size of your home
• the devices you want to connect to the wireless network

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How To: Set Up a Network (2 of 5)

How To: Set Up a Network (3 of 5)

• Adding a wireless printer to a home or small office network has several advantages.
• Multiple computers and mobile devices on the network can use the printer.
• Once the printer is installed on the network, you can download an app from the manufacturer to send documents to the printer from network-connected devices.

Figure 9-12 Sending a document to a wireless printer.

How To: Set Up a Network (4 of 5)

• Set the location of the wireless printer within the range of the wireless network
• Place the printer on a stable surface
• Access the printer’s settings and navigate to the network settings
• Connect to the wireless network in your home or small office
• Enter any remaining required information
• Install the printer app on the computer(s) and devices from which you want to print to the wireless printer

How To: Set Up a Network (5 of 5)

• If your wireless router or wireless access point has an antenna(s), extend it completely
• If you can remove the antenna(s) from your wireless router or wireless access point, replace it with a wireless signal booster
• Place the wireless router or wireless access point in a central location of your home
• Purchase a booster (or repeater), which is an amplifier used to improve reception and extend the range
• Change the router if problems persist

Figure 9-13 Wireless signal booster.

Secure IT: Secure a Network (1 of 5)

• Wireless Networks are easily accessible.
• It leads to several common network risks.
• Change the default password for the wireless access point, the SSID name, encryption, and a MAC address
• Keep a regular check on the number of connected devices to the wireless router

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Secure IT: Secure a Network (2 of 5)

Table 9-6 Common network risks.

Secure IT: Secure a Network (3 of 5)

Figure 9-14 Securing a network.

Encryption scrambles or codes data as it

is transmitted over a network.

The Network attached storage (NAS) devices provide a centralized location for storing programs and data on large and small networks.

Authentication identifies you to

the network. The most common type of authentication

is providing a username and

password.

Firewalls create a blockade between corporate or personal

Networks and the Internet.

Biometric devices authenticate identity by scanning your physical

characteristics, such

as a fingerprint.

Secure IT: Secure a Network (4 of 5)

• Network monitoring software constantly assesses the status of a network and sends an email or text message, when it detects a problem.
• Monitoring software can measure the amount of network traffic, graph network usage, determine when a specific program uses the network, and show the bandwidth used by each computer or mobile device.
• Packet sniffer software monitors and logs packet traffic for later analysis.
• Hackers use packet sniffer software to hijack a computer.

Secure IT: Secure a Network (5 of 5)

Use the following steps to determine if someone is accessing a wireless network without permission:

• Sign in to the administrative interface
• Count the number of connected devices
• Secure the network
• Enable the router’s firewall and, if possible, use “stealth mode” to make the network less visible to outsiders

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Ethics and Issues: Responsibilities of a�Network Professional (1 of 2)

• The role of a network administrator is to plan, design, purchase equipment for, set up, secure, and maintain a network.
• USENIX is a nonprofit organization that was founded in 1975 to support network and system engineers and operators in innovation and research.

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Figure 9-15 A network administrator is in a position of trust.

Ethics and Issues: Responsibilities of a�Network Professional (2 of 2)

• Professionalism
• Social Responsibility
• Personal Integrity
• Privacy
• Laws and Policies
• Communication
• System Integrity
• Education
• Responsibility to Computing Community
• Ethical Responsibility

The code includes guidelines for: