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Technology in ActionChapter 13Behind the Scenes: How the Internet WorksCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall

0This chapter takes you behind the scenes of the Internet. We look at how the Internet works and the various standards it follows. Along the way, we also go behind the scenes of some Internet communication features, such as e-mail and instant messaging services. We discuss just how safe these features are and what you can do to make your communications even more secure.

ObjectivesTo learn on how to manage the InternetTo know what Internet networking and identity areTo learn on how data is transmitted and what protocols involvedTo know various protocols and communications over the InternetCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall1

1Chapter topics include:Management of the InternetInternet networkingData transmission and protocolsInternet identityHTTP, HTML, and Other Web Building BlocksCommunications over the Internet

Management of the InternetLocal networks are owned by: IndividualsUniversitiesGovernment agenciesPrivate companiesManaged by nonprofit organizations and user groups

Copyright 2013 Pearson Education, Inc. Publishing as Prentice Hall2

2The Internet is the largest network in the world. To keep a massive network like the Internet functioning at peak efficiency, it must be governed and regulated. However, no single entity is in charge of the Internet. In addition, new uses are created every day by a variety of individuals and companies.Even though the U.S. government funded the development of the technologies that spawned the Internet, no one really owns it. The particular local networks that constitute the Internet are all owned by different entities, including individuals, universities, government agencies, and private companies. Government entities such as the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA), as well as many large, privately held companies, own pieces of the communications infrastructure (the high-speed data lines that transport data between networks) that makes the Internet work.Because the individual networks that participate in the Internet are owned by several different entities, the Internet would cease to function without some sort of organization. Therefore, several nonprofit organizations and user groups, each with a specialized purpose, are responsible for its management.

Internet NetworkingMuch information is now stored out in the cloudYou can retrieve information stored on servers around the worldEnter a URL in your browserEnter a search topic in a search engineSeries of communication transactions enable Internet to function as global networkCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall3

The Internets response to our requests for information seems almost magical at times since so much information is now stored out in the cloud. By simply entering a URL in your browser or going to a search engine and entering a search topic, you can summon up information that is stored on servers around the world. However, there is no magic involved, just a series of communication transactions that enable the Internet to function as a global network. In this section, we explore the various networks that make up the Internet, explain how to connect to them, and examine the workings of Internet data communications.

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Connecting to the Internet Internet backboneCollection of large national and international networksT lines: Initially used for backbone ISP connectionsCarried digital data over twisted-pair wiresOptical carrier line (OC): Todays most common backbone ISP connectionHigh-speed, fiber-optic lines designed to provide high throughputCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall4

4The main paths of the Internet along which data travels the fastest are known collectively as the Internet backbone.The backbone is a collection of large national and international networks, most of which are owned by commercial, educational, or government organizations (such as NASA). These backbone providers are required to be connected with other backbone providers and have the fastest high-speed connections. Some large companies that provide backbone connectivity included Verizon Business, AT&T, Sprint, and Qwest.Initially backbone ISPs connected through T lines. T lines carried digital data over twisted-pair wires. T-1 lines were the first to be used and transmitted data at a throughput rate of 1.544 Mbps. T-3 lines, which were developed later, transmit data at 45 Mbps. Today, backbones are typically high-speed, fiber-optic lines, designated as optical carrier (OC) lines. OC lines come in a variety of speeds.

Network Model of the InternetInternet communications follow the client/server network model of network communicationsClients request servicesServers provide services to clientsCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall5

5The majority of Internet communications follows the client/server model of network communications, which we defined in earlier chapters as one in which client computers request services and other computers, known as servers, provide those services to the clients. In the case of the Internet, the clients are devices such as computers, tablets, and smartphones that use browsers (or other interfaces) to request services such as Web pages. Various types of servers from which clients can request services are deployed (installed) on the networks that make up the Internet.

Types of ServersWeb serversHost Web pagesCommerce serversEnable the purchase of goods and services over the WebFile serversProvide remote storage space for files that users can downloadCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall6

6There are various types of servers deployed on the networks that make up the Internet and from which clients can request services.Web servers run specialized operating systems that enable them to host Web pages and provide requested Web pages to clients.Commerce servers host software that enables users to purchase goods and services over the Web. These servers generally use special security protocols to protect sensitive information (such as credit card numbers) from being intercepted.File servers are deployed to provide remote storage space or to act as a repository for files that users can download.

Peer-to-Peer File SharingCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall7

7Certain services on the Internet operate in a peer-to-peer (P2P) mode.For example, BitTorrent is a popular file-sharing service through which Internet users can exchange files. BitTorrent and other file-sharing services require the users computer to act as both a client and a server. When requesting files from another user, the computer behaves like a client. It switches to server mode when it provides a file stored on its hard drive to another computer.

Data Transmission and ProtocolsComputer protocol is a set of rules for exchanging electronic information Internet protocols had to be an open system designNetworks can communicate even if they have different topologies, transmission media, or operating systemsCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall8

8Just like any other network, the Internet follows standard protocols to send information between computers. A computer protocol is a set of rules for exchanging electronic information. If the Internet is the information superhighway, then protocols are the rules of the road.To accomplish the early goals of the Internet, protocols needed to be written and agreed upon by users. Each protocol had to be an open system, meaning its design would be made public for access by any interested party. This was in direct opposition to the proprietary system (private system) model that was the norm at the time.As we mentioned in earlier chapters, when common communication protocols (rules) are followed, networks can communicate even if they have different topologies, transmission media, or operating systems. The idea of an open system protocol is that anyone can use it on his or her computer system and be able to communicate with any other computer using the same protocol. The biggest Internet taskscommunicating, collaborating, creating content, seeking information, and shoppingare all executed the same way on any system that is following accepted Internet protocols.

Circuit SwitchingTechnology available in 1960sDedicated connection is formed between two pointsRemains active for duration of transmissionUsed since early days of the telephone communicationsInefficient for computersCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall9

9Agreeing on common standards was relatively easy. The tough part was developing a new method of communication because the technology available in the 1960scircuit switchingwas inefficient for computer communication. Circuit switching has been used since the early days of the telephone for establishing communication. In circuit switching, a dedicated connection is formed between two points (such as two people on telephones), and the connection remains active for the duration of the transmission. This method of communication is extremely important when communications must be received in the order in which they are sent (again, like telephone conversations).When applied to computers, however, circuit switching is inefficient. Computers process communication in bursts. As a computer processor performs the operations necessary to complete a task, it transmits data in a group (or burst). The processor then begins working on its next task and ceases to communicate with output devices or other networks until it is ready to transmit data in the next burst. Circuit switching is inefficient for computers because the circuit either would have to remain open (and therefore unavailable to any other system) with long periods of inactivity or would have to be reestablished for each burst.

Packet SwitchingMakes computer communication efficientData is broken into small units (packets)Packets are sent over various routes to their destinationPackets are reassembled by the receiving computerCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall10

10Packet switching is the communications methodology that makes computer communication efficient. Packet switching doesnt require a dedicated communications circuit to be maintained. With packet switching, data is broken into smaller chunks (each one called a packet or a data packet) that are sent over various routes at the same time. When the packets reach their destination, they are reassembled by the receiving computer. This technology resulted from one of the original goals of creating the Internet: If Internet nodes are disabled or destroyed (such as through an act of warfare or terrorism), the data can travel an alternate route to its destination.

Packet ContentsContents vary depending on protocolAt a minimum, all packets must contain:Address to which packet is being sentAddress from where packet originatesReassembling instructions, if original data was splitData that is being transferredCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall11

Packet contents vary, depending on the protocol being followed. At a minimum, all packets must contain (1) an address to which the packet is being sent; (2) the address from where the packet originates; (3) reassembling instructions, if the original data was split between packets; and (4) the data that is being transmitted.

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TCP/IPMain suite of protocols used on InternetTransmission Control Protocol (TCP)Prepares data for transmissionProvides error checkingEnables resending lost dataInternet Protocol (IP)Responsible for sending information from one computer to anotherCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall12

12Although many protocols are available on the Internet, the main suite of protocols used is TCP/IP. The suite is named after the original two protocols that were developed for the Internet: the Transmission Control Protocol (TCP) and the Internet Protocol (IP). Transmission Control Protocol (TCP) prepares data for transmission and provides for error checking and resending lost data.Internet Protocol (IP) is responsible for sending the information from one computer to another.

Internet IdentityEach computer, server, or device connected to the Internet is required to have unique identification numberNumeric IP addresses were given more human word-based addressedDomain names were bornCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall13

Each computer, server, or device (such as a router) connected to the Internet is required to have a unique identification number. However, because humans are better at remembering and working with words than with numbers, the numeric IP addresses were given more human, word-based addresses. Thus, domain names were born.

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IP AddressUnique number that identifies each device connected to the InternetTypical IP address 197.24.72.157Static addressingIP Address never changesDynamic addressingTemporary address from available poolCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall14

14A typical IP address is expressed as a dotted decimal number or a dotted quad, such as the one on the slide. IP addresses are assigned either statically or dynamically. Static addressing means that the IP address for a computer never changes and is most likely assigned manually by a network administrator or ISP. In dynamic addressing, your computer is assigned a temporary address from an available pool of IP addresses.

Domain NamesDomain name takes place of an IP addressEasier to rememberOrganized by levelTop-level domain (TLD)Portion of the domain name that follows the dotIncludes .com, .org, .gov, .edu, and .netSecond-level domainUnique name within a top-level domainYahoo.com, Whitehouse.gov, Unesco.orgCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall15

15A domain name is simply a name that takes the place of an IP address, making it easier for people to remember. For example, www.mywebsite.com is a domain name.Domains are organized by level. The portion of the domain name farthest to the right (after the dot) is the top-level domain (TLD). TLDs (such as .com and .org) are standardized pools established by ICANN.Within the top-level domains are many second-level domains. In the .com domain, there are popular sites such as Amazon.com, Google.com, and Microsoft.com. Each of the second-level domains needs to be unique within that particular domain, but not necessarily unique to all top-level domains. For example, Mycoolsite.com and Mycoolsite.org could be registered as separate domain names.

Domain Name System ServersInternet servers that translate domain names into IP addressesISPs go first to a default DNS to resolve a nameName queries work up the hierarchy to the root DNS servers if requiredCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall16

16Say you want to get to Google.com. To do so, you type the URLwww.google.cominto your browsers address box. However, the URL is not important to your computer; only the IP address of the computer hosting the Google site is. When you enter the URL in your browser, your computer must convert the URL to an IP address. To do this, your computer consults a database that is maintained on a DNS (Domain Name System) server that functions like a phone book for the Internet.Your ISPs Web server has a default DNS server (one that is convenient to contact) that it goes to when it needs to translate a URL to an IP address. It uses the following steps:Your browser requests information from ABC.com.Your ISP doesnt know the address of ABC.com, so it requests the address from its default DNS server.The default DNS server doesnt know the IP address of ABC.com either, so it queries the root server of the .com domain.The root server provides the default DNS server with the appropriate IP address of ABC.com.The default DNS server stores the correct IP address for ABC.com for future reference and returns it to your ISPs Web server.Your computer then routes its request to ABC.com and stores the IP address in cache for later use.Your ISP or network administrator defines the default DNS server. If the default DNS server does not have an entry for the domain name you requested, then it queries another DNS server.If all else fails, your ISPs Web server will contact one of the 13 root DNS servers maintained throughout the Internet. Each root DNS server knows the location of all the DNS servers that contain the master listings for an entire top-level domain. Your default DNS server receives the information from the master DNS server (say, for the .com domain). It then stores that information in its cache for future use and communicates the appropriate IP address to your computer.

DNS Servers in ActionCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall17

DNS servers in action.17

HTTP, HTML, and Other Web Building BlocksWorld Wide Web is grouping of protocols and software that resides on InternetWeb uses special languages and protocols to facilitate communication between computersCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall18

Although most people think that the Internet and the Web are the same thing, the World Wide Web (WWW or the Web) is actually a grouping of protocols and software that resides on the Internet. The Web provides an engaging interface for exchanging graphics, video, animations, and other multimedia over the Internet. One other aspect that distinguishes the Web from the Internet is the Webs use of special languages such as HTML (HyperText Markup Language) and protocols such as HTTP (HyperText Transfer Protocol), which facilitate communication between computers using different system and application software.

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Web Browser Security ProtocolsHyperText Transfer Protocol (HTTP)For transfer of hypertext documentsHyperText Transfer Protocol Secure (HTTPS)Combination of HTTP and network security protocol Transport Layer Security (TLS) and Secure Sockets Layer (SSL)Protect data integrity of data and security of transmissions over the Internet

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The HyperText Transfer Protocol (HTTP) was created especially for the transfer of hypertext documents across the Internet. Hypertext documents are documents in which text is linked to other documents or media (such as video clips, pictures, and so on). Clicking a specific piece of text (called a hyperlink) that has been linked elsewhere takes you to the linked file.HyperText Transfer Protocol Secure (HTTPS) is actually a combination of HTTP and a network security protocol (usually SSL or TLS). HTTPS ensures data is sent securely over the Web.Transport Layer Security (TLS) and the Secure Sockets Layer (SSL) are two protocols that provide data integrity and security for transmissions over the Internet. Online shopping sites frequently use HTTPS to safeguard credit card information. Online banking sites and other Web sites that require user authentication beyond just a simple user ID and password also use HTTPS.

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HTML/XHTMLWeb page is a text document formatted using Web languagesHyperText Markup Language (HTML)eXtensible HyperText Markup Language (XHTML)Sets of rules for marking up blocks of text so browser know how to display themCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall20

20A Web page is a text document that is formatted using HyperText Markup Language (HTML) or Extensible HyperText Markup Language (XHTML). Although XHTML is the development environment of choice for Web developers today, many people still refer to Web site formatting as HTML tagging.HTML/XHTML are not programming languages; rather, they are sets of rules for marking up blocks of text so that a browser knows how to display them.

XMLeXtensible Markup Language (XML)Designed for exchanging informationCan be used to create your own markup languageUsed in e-commerce transactionsCustom packages for specific communitiesMathML, Wireless Markup Language (WML)

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21Because HTML/XHTML is not designed for exchanging information, XML is used. Extensible Markup Language (XML) allows users to build their own markup languages to accommodate particular data formats and needs, instead of being locked into standard tags and formats.XML has spawned quite a few custom packages for specific communities. For example, Mathematical Markup Language (MathML) is an XML-based markup language used to describe mathematical symbols and formulas so that they can be presented in a familiar way in Web documents. Wireless Markup Language (WML) uses XML to output Web resources on mobile devices.

Common Gateway InterfaceProvides methodology so browsers can request that a program file be executedCGI files are often called CGI scriptsAdds Web page interactionAdding names to guest books/mailing listsCompleting formsCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall22

22To make a Web site interactive, you may need to run a program to perform a certain action (such as gathering a name and address and adding them to a database). The Common Gateway Interface (CGI) provides a methodology by which your browser can request that a program file be executed (run) instead of just being delivered to the browser. This enables functionality beyond the simple display of information.CGI files can be created in almost any programming language, and the programs created are often referred to as CGI scripts. Common languages that are used to create CGI scripts are Perl, C, and C++. Because programming languages are extremely powerful, almost any task can be accomplished by writing a CGI script. You have probably encountered CGI scripts on Web pages without realizing it. Have you used a search engine to create a customized results page based on keywords you entered? Have you filled out a form in which you asked to be added to a mailing list? Both of these tasks are commonly done using CGI scripts.On most Web servers, a directory called cgi-bin is created by the network administrator who configures the Web server. All CGI scripts are placed into this directory. The Web server knows that all files in this directory are not just to be read and sent but also need to be run. Because this type of program runs on the Web server rather than inside your browser, it is referred to as a server-side program.For instance, a button on bookuniverse.coms Web site may say Click Here to Join Mailing List. Clicking the button may execute a script file (perhaps called mailinglist.pl) from the cgi-bin directory on the Web server hosting the site (step 2). This file generates a form that is sent to your browser (step 3). The form includes fields for a name and e-mail address and a button that says Submit. After you fill in the fields and click the Submit button, the mailinglist.pl program sends the information back to the server (step 4). The server then records the information in a database.

Dynamic HTMLA combination of technologies used to create interactive Web sitesHTML/XHTMLCascading style sheetsJavaScriptCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall23

23Dynamic HTML (DHTML) is a combination of technologiesHTML/XHTML, cascading style sheets, and JavaScriptthat is used to create lively and interactive Web sites. Recall that the Web is based on a client/server network. Once a Web server processes a Web page and sends the page to the computer that requested it (the client), the receiving computer cannot get any new data from the server unless a new request is made. If interactivity is required on a Web page, this exchange of data between the client and server can make the interactivity inefficient and slow. DHTML technologies allow a Web page to change after it has been loaded. Change generally occurs in response to such user actions as clicking a mouse or mousing over objects on a page. DHTML brings special effects to otherwise static Web pages without requiring users to download and install plug-ins or other special software.

AJAX and JavaScriptAsynchronous JavaScript and XML (AJAX)Newer group of technologies that facilitates creation of Web applicationsDoes not actually require JavaScript or XMLJavaScriptMost commonly used scripting language for creating DHTML effectsCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall24

24AJAX is the acronym for Asynchronous JavaScript and XML, a newer group of technologies that facilitates the creation of Web applications. These technologies can update information on the page without requiring the user to do a page refresh or leave the page. AJAX does not actually require the use of JavaScript or XML (even though they are in the name) but can use a variety of Web programming techniques and languages. JavaScript and XML are frequently used by AJAX Web developers.JavaScript is the most commonly used scripting language for creating DHTML effects. It was developed through the joint efforts of Netscape and Sun Microsystems, two software development companies. JavaScript is often confused with the Java programming language because of the similarity in their names. However, though they share some common elements, the two languages function quite differently.

Cascading Style SheetsList of statements that defines in a single location how to display HTML/XHTML elements Enable a Web developer to define a style for each HTML/XHTML element and apply it to multiple elements on many Web pagesAllows for creation of formatting templates

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25A cascading style sheet (CSS) is a list of statements (also known as rules) that defines in one single location how to display HTML/XHTML elements. Style rules enable a Web developer to define a style for each HTML/XHTML element and apply it to multiple elements on as many Web pages as needed. Essentially, a template is created upon which the formatting for many Web pages within a site will be based. Thus, when a global change is necessary, the developer only needs to change the style on the style sheet (template); all the elements in the Web document are then updated automatically.Cascading style sheets allow for the creation of formatting templates. Just as all the pages of this book have a similar look and feel, one style sheet can control the formatting of many Web pages.

Client Side ApplicationsPrograms that run on client computer with no interaction with a Web serverTwo main types:Embedding programming language code directly within HTML or XHTML code of a Web pageApplet is a small application that resides on a server and when requested, compiled version is downloaded to client computer

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Often it is more efficient to run programs on your computer (the client). Therefore, client-side programs were created. A client-side program is a computer program that runs on the client computer and requires no interaction with a Web server. Client-side programs are fast and efficient because they run on your desktop and dont depend on data going back and forth to the Web server. Two main types of client-side methods exist. The first involves embedding programming language code directly within the HTML or XHTML code of a Web page using an HTML/XHTML embedded scripting language. The most popular embedded language is JavaScript, which is used extensively in dynamic HTML files.The second type of client-side program is an applet, a small application that resides on a server. When requested, a compiled version of the program is downloaded to the client computer and run there. The Java language is the most common language used to create applets for use in browsers. The applets can be requested from the server when a Web page is loaded; they will run once theyre downloaded to the client computer.26

Communications over the InternetCommunications revolution began to explode in the mid 1990sInternet e-mailGrowing exponentially each month97 percent is spamTexting and instant messagingVoice over Internet protocolCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall27

A new communications revolution was started when Internet use began to explode in the mid-1990s. The volume of Internet e-mail is growing exponentially every month. Unfortunately, it is estimated that 97 percent of it is spam. Texting and instant messaging are both popular methods of communication, and the popularity of Voice over Internet Protocol is also on the rise. 27

E-MailSimple Mail Transfer Protocol (SMTP) is used for sending e-mail along InternetPopular client-based e-mail software:Microsoft OutlookMozilla ThunderbirdWeb-based e-mail softwareGmailYahoo!HotmailCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall28

Just like other kinds of data that flow along the Internet, e-mail has its own protocol. The Simple Mail Transfer Protocol (SMTP) is responsible for sending e-mail along the Internet to its destination. SMTP is part of the Internet Protocol suite. As in most other Internet applications, e-mail is a client/server application. To send an e-mail message, you will need some form of e-mail software to compose the document as well as to include an attachment such as a spreadsheet or photograph. Popular client-based e-mail software (software that needs to be installed on your computer) includes Microsoft Outlook and Mozilla Thunderbird, as well as Web-based e-mail software such as Gmail, Yahoo!, and Hotmail.

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E-Mail (cont.)Multipurpose Internet Mail Extensions (MIME) simplifies attachments to e-mail messagesHandles encoding and decodingCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall29

The Multipurpose Internet Mail Extensions (MIME) specification was introduced in 1991 to simplify attachments to e-mail messages. All e-mail client software now uses this protocol to attach files.E-mail is still sent as text, but the e-mail client using the MIME protocol now handles the encoding and decoding for the users. For instance, when attaching a file, you click the attachment icon (usually a paperclip) and browse to the file you want to attach (located somewhere on a storage device).. Your e-mail client transparently encodes and decodes the file for transmission and receipt.

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Instant MessagingAct of communicating with one or more people in real timeTop IM programsAOL Instant Messenger (AIM)GoogleTalkYahoo! MessengerJabberWindows Live MessengerCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall30

30instant messaging is the act of communicating over the Internet with one or more people in real time. It differs from e-mail in that conversations are able to happen at the same time rather than lagging by minutes or hours. Although you may not use instant messaging services (beyond the service offered on Facebook), businesses today routinely use these services to keep employees in constant contact.Instant messaging requires the use of a client program that connects to an instant messaging service. AOL Instant Messenger (AIM), GoogleTalk, Yahoo! Messenger, Jabber, and Windows Live Messenger are the top five instant messaging services in use today. No matter which one you choose, you need to have the appropriate client software installed on your computing device. Instant messaging programs are often used on smartphones and tablets because it provides for real time conversations with multiple individuals, including employees who may be at their desks and not using mobile devices.

How Instant Messaging WorksCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall31

31In instant messaging, the client software running on your computer makes a connection with the chat server, using your Internet connection. Once contact is established, you can log in to the server with your name and password. The client software provides the server with connection information for your computer. The server then consults the list of contacts that you have previously established in your account and checks to see if any of your contacts are online. If any are, the server sends a message back to your client providing the necessary connection information (the IP addresses) for your friends. You can now click your friends names to establish a chat session with them.

Voice over Internet Protocol (VoIP)Turns standard Internet connection into way to make free long-distance phone callsCollection of communication and transmission protocolsUses TCT/IP protocols to route phone calls across the InternetCopyright 2013 Pearson Education, Inc. Publishing as Prentice Hall32

32Voice over Internet Protocol (VoIP) turns a standard Internet connection into a way to make free long-distance phone calls. VoIP is not part of the TCP/IP suite but is a collection of communication and transmission protocols that uses TCP/IP protocols to route phone calls across the Internet.

Chapter 13 Summary QuestionsWho owns, manages, and pays for the Internet? How do the Internets networking components interact?What data transmissions and protocols does the Internet use?Why are IP addresses and domain names important for Internet communications?What are HTTP, HTML/XHTML and XML used for?How do e-mail, instant messaging, and Voice over Internet Protocol work, and how is information using these technologies kept secure?

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331. Who owns, manages, and pays for the Internet?Management of the Internet is carried out by several nonprofit organizations and user groups such as the Internet Society (ISOC), the Internet Engineering Task Force (IETF), the Internet Architecture Board (IAB), the Internet Corporation for Assigned Names and Numbers (ICANN), and the World Wide Web Consortium (W3C). Each group has different responsibilities and tasks. Currently, the U.S. government (and subsequently the U.S. taxpayer) funds a majority of the Internets costs.