1Slide 1Tomorrow’s Technologyand You8th Edition© 2008 Prentice-Hall, Inc.Slide 2Tomorrow’s Technologyand You 8/eChapter 9The Evolving Internet© 2008 Prentice-Hall, Inc.Slide 3Tomorrow’s Technology and You 8/eChapter 9Objectives Explain how and why the Internet was created. Describe the technology that is at the heart of the Internet. Describe the technology that makes the Web work as amultimedia mass medium. Discuss the tools people use to build Web sites.© 2008 Prentice-Hall, Inc.2Slide 4Tomorrow’s Technology and You 8/eChapter 9Objectives (continued) Discuss the trends that are changing the Internet and the waypeople use it. Discuss some of the most important social and political issuesraised by the growth of the Internet. Describe various ways that governments restrict access to theInternet.© 2008 Prentice-Hall, Inc.Slide 5Tomorrow’s Technology and You 8/eChapter 9ARPANET Pioneers Build a Reliable NetworkOut of Unreliable Parts The Advanced Research Projects Agency NETwork (ARPANET)is the predecessor to the Internet: Developed at the request of the Department of Defense by a team ofvisionary computer scientists Launched in 1969 Peer-to-peer networking philosophy and protocols were copied in othernetworks in the 1980s Disbanded in 1990, having fulfilled its research mission, but its technologyspawned the Internet© 2008 Prentice-Hall, Inc.Slide 6Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetCounting ConnectionsThe Internet: an interconnected networkof thousands of networks Links academic, research, government, andcommercial institutionsConnects computers to about everycountry in the world Growing too fast to measure its growth Internet is decentralized Internet doesn’t have hard boundaries© 2008 Prentice-Hall, Inc.3Slide 7Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Protocols Transmission Control Protocol/Internet Protocol, TCP/IP… At the heart of the Internet Allows cross-network communication TCP breaks messages into packets. Each packet has all the information needed to travel from network tonetwork. Host systems called routers determine how to route transmissions. Packet-switching is flexible and robust.© 2008 Prentice-Hall, Inc.Slide 8Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Protocols IP is the address for the packets. Each Internet host computer has a unique IP address. Each address is comprised of four sets of numbers separated by periods,such as 123.23.168.22. NextGeneration Internet will allow more addresses and multicasting.© 2008 Prentice-Hall, Inc.Slide 9Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Addresses The host is named using DNS (domain name system), whichtranslates IP addresses into a string of names. Top-level domains include: .edu - educational sites .com - commercial sites .gov - government sites .mil - military sites .net - network administration sites .org - nonprofit organization sites© 2008 Prentice-Hall, Inc.4Slide 10Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Addresses .aero Air transport organizations .biz Businesses .coop Cooperative businesses such as credit unions .info Information services .museum Museums .name Personal registration by name .pro Licensed professionals, including lawyers, doctors, and accountants© 2008 Prentice-Hall, Inc.Slide 11Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetAn email address includes:[email protected] username is the person’s“mailbox” hostname is the name of the hostcomputer and is followed by oneor more domains separated byperiods: host.domain host.subdomain.domain host.subdomain.subdomain.domain© 2008 Prentice-Hall, Inc.Slide 12Tomorrow’s Technology and You 8/eChapter 9 Inside the Internet© 2008 Prentice-Hall, [email protected] President whose mail isstored on the host whitehouse inthe government [email protected] hazel_filbert at the adminserver for Grant MacEwanCommunity College in Alberta,Canada5Slide 13Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Access Options Direct (Dedicated) ConnectionComputer has its own IP address and isattached to a LANNo need to dial upFiles are stored on your computerQuick response time Dialup ConnectionLimited connection using a modemFull access dialup uses POTS or PPP viamodem© 2008 Prentice-Hall, Inc.Slide 14Tomorrow’s Technology and You 8/eChapter 9 Inside the Internet Internet Access OptionsBroadband Connections DSL Service Newer, faster, and cheaper than ISDN Can share phone line with voice traffic Cable Modem Connection Allows Internet connections using shared TV cables Can exceed DSL speeds Carries increased privacy and security risks© 2008 Prentice-Hall, Inc.Slide 15Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Access Options Satellite connection provides connectionusing DirecTV satellite dishes. Wireless broadband connection allowsmultiple computers to connect to a basestation using short-range radio waves.Internet Service Providers (ISPs) Local ISPs provide connections through local telephone lines. National ISPs offer connections on a nationwide scale. Online Services like AOL and MSN offer extra services.© 2008 Prentice-Hall, Inc.6Slide 16Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Servers E-mail server acts like a local post office for a particular Internet host—abusiness, an organization, or an ISP. File servers are common within LANs. Also used to share programs, media files, and other data across the Internet File transfer protocol (FTP) allows users to transfer files. Download files from remote servers to their computers Upload files to remote computers File compression saves storage space on disk and saves transmission time whenfiles are transferred through networks.© 2008 Prentice-Hall, Inc.Slide 17Tomorrow’s Technology and You 8/eChapter 9 Inside the InternetInternet Servers Application server stores applications—PC office applications, databases,or other applications. Makes them available to client programs that request them Might be housed at an application service provider (ASP),