Transcript M9-Internet
1 January 2011 [email protected] 1 321450 Management of Information Technology Chapter 8 Internet and Information Systems Asst. Prof. Wichai Bunchua E-mail : [email protected] http://www.informatics.buu.ac.th/~wichai Why Learn About the Internet? Internet is an important part of most people’s lives Individuals can investigate career opportunities Businesses sell and advertise online Employees can communicate with coworkers and bosses 1 January 2011 [email protected] 33 The Internet Internet: ? 1 January 2011 [email protected] 44 The Internet Internet: a collection of interconnected networks, all freely exchanging information ARPANET Ancestor of the Internet Project started by the U.S. Department of Defense (DoD) in 1969 1 January 2011 [email protected] 55 The Internet Table 1: A Brief History of the Internet 1 January 2011 [email protected] 66 Internet Hosts 1 January 2011 [email protected] 77 How the Internet Works Internet transmits data from one computer (called a host) to another If the receiving computer is on a network to which the first computer is directly connected, it can send the message directly If the receiving computer is not on a network to which the sending computer is connected, the sending computer relays the message to another computer that can forward it Data is passed in chunks called packets 1 January 2011 [email protected] 88 How the Internet Works (continued) 1 January 2011 [email protected] 99 How the Internet Works Transmission Control Protocol (TCP) Transport-layer protocol that most Internet applications use with IP Internet Protocol (IP): communication standard that enables traffic to be routed from one network to another as needed Backbone One of the Internet’s high-speed, long-distance communications links 1 January 2011 [email protected] 1010 How the Internet Works (continued) Internet Corporation for Assigned Names and Numbers (ICANN) Responsible for managing IP addresses and Internet domain names Has authority to resolve domain name disputes Cyber-squatters Register domain names in the hope of selling them to corporations or people 1 January 2011 [email protected] 1111 Domain Name Registrations (2000-) 1 January 2011 [email protected] 1212 How the Internet Works (continued) Accessing the Internet Connect via LAN Server Connect via Dial-up Connect via High-Speed Service Connect Wirelessly 1 January 2011 [email protected] 13 How the Internet Works (continued) 1 January 2011 [email protected] 14 Internet Service Providers Any company that provides individuals or organizations with access to the Internet Most charge a monthly fee 1 January 2011 [email protected] 1515 Internet Service Providers (continued) เครื อข่าย ผูใ้ ห้บริ การ บริษัท กสท. โทรคมนาคม จากัด (มหาชน) http://www.cat.net.th/ บริษัท อินเทอร์ เน็ตประเทศไทย จากัด (มหาชน) http://www.inet.co.th/ บริษัท สามารถอินโฟเนต จากัด http://www.samarts.com/ บริษัท ทีทแี อนด์ ที จากัด (มหาชน) http://www.ttt.co.th/ บริษัท ทีโอที จากัด (มหาชน) http://www.tot.co.th/ บริษัท ซีเอส ล็อกซอินโฟ จากัด (มหาชน) http://www.csloxinfo.com/ บริษัท ทรู อินเทอร์ เน็ต จากัด http://www.trueinternet.co.th/ 1 January 2011 [email protected] 16 The World Wide Web 1 January 2011 [email protected] 1717 The World Wide Web Collection of tens of millions of server computers that work together as one in an Internet Hyperlink Highlighted text or graphics in a Web document that, when clicked, opens a new Web page 1 January 2011 [email protected] 1818 The World Wide Web The World Wide Web was developed by Tim Berners-Lee at CERN, The European Organization for Neuclear Research in Geneva [Center Europeane pour la Recherche Nucleaire] 1 January 2011 [email protected] 1919 WWW Growth 1 January 2011 [email protected] 2020 The World Wide Web (continued) Hypertext Markup Language (HTML) HTML tags Let the browser know how to format text Extensible Markup Language (XML) Standard page description language for Web pages Markup language for Web documents containing structured information Cascading Style Sheet (CSS) File or portion of an HTML file that defines the visual appearance of content in a Web page 1 January 2011 [email protected] 2121 The World Wide Web (continued) Web Documents index.html HTML Documents/ Linked Files http://www.buu.ac.th/index.html REQUEST HTTP The Internet HTTP HTTPD Client Web Browser 1 January 2011 HTML Document index.html Web Page Home Page [email protected] Web Server Web Site 22 Web Browsers Web browser: software that creates a unique, hypermediabased menu on a computer screen, providing a graphical interface to the Web Menu consists of graphics, titles, and text with hypertext links Popular Web browsers: Microsoft Internet Explorer, Netscape Navigator, Mozilla Firefox, Apple Computer’s Safari Uniform Resource Locator (URL) An assigned address on the Internet for each compute 1 January 2011 [email protected] 2323 Web Browsers (continued) 1 January 2011 [email protected] 24 Search Engines and Web Research Search engine: Web search tool Examples: Yahoo.com, Google.com Most search engines are free Searches can use words, such as AND and OR to refine the search Meta-search engine: submits keywords to several individual search engines and returns results from all these search engines 1 January 2011 [email protected] 2525 Search Engines and Web Research (continued) Table 6 Popular Search Engines 1 January 2011 [email protected] 2626 Web Programming Languages Java Object-oriented programming language from Sun Microsystems based on C++ Allows small programs (applets) to be embedded within an HTML document Other languages Asynchronous JavaScript and XML (AJAX) Hypertext Preprocessor (PHP) Adobe Flash and Microsoft Silverlight 1 January 2011 [email protected] 2727 Web Programming Languages (continued) Figure : Downloading an Applet from a Web Server 1 January 2011 [email protected] 2828 Developing Web Content Popular tools for creating Web pages and managing Web sites: Popular publishing options: Adobe Dreamweaver, Microsoft Expression Web, and Nvu ISPs, free sites, and Web hosting Mash-up Process of mixing two or more hip-hop songs into one song 1 January 2011 [email protected] 2929 Developing Web Content Suggestions for creating a Web page • • • Computer must be linked to a Web server Web browser program needed to view the HTML pages you create Options for designing the Web page • • • • 1 January 2011 Write your copy with a word processor, and use an HTML converter to convert the page into HTML format Use an HTML editor to write text and add HTML tags Edit an existing HTML template to meet your needs Use an ordinary text editor and type the start and end tags for each item [email protected] 3030 Internet and Web Applications The types of Internet and Web applications available are vast and ever expanding 1 January 2011 [email protected] 3131 Business Uses of the Web In 1991, Commercial Internet Exchange (CIX) Association was established to allow businesses to connect to the Internet Firms use the Internet for many types of applications 1 January 2011 [email protected] 3232 Internet and Web Applications Search engines and Web research Search engines Have become important to businesses as a tool to drive visitors to the business’ Web site SEO has become a valuable marketing tool 1 January 2011 [email protected] 33 1 January 2011 [email protected] 34 E-Mail, Instant Messaging, and Video Chat E-mail No longer limited to simple text messages Can embed sound and images Can attach files Instant messaging Online, real-time communication between two or more people who are connected to the Internet 1 January 2011 [email protected] 3535 Internet Cell Phones and Handheld Computers Cell phones connected to the Internet allow people to search for information, buy products, and chat with business associates and friends Short Message Service (SMS) or texting Brief text messages can be sent between two or more cell phone users Handheld computers and other devices are connected to the Internet using phone lines or wireless connections 1 January 2011 [email protected] 3636 Career Information and Job Searching Search engines Good starting point for searching for specific companies or industries Job sites www.directmarketingcareers.com www.monster.com www.hotjobs.com www.careerbuilder.com 1 January 2011 [email protected] 3737 Telnet, SSH, and FTP Telnet Secure Shell (SSH) Network protocol that enables users to log on to networks remotely over the Internet Provides Telnet functionality through a more secure connection File Transfer Protocol (FTP) Supports file transfers between a host and a remote computer 1 January 2011 [email protected] 3838 SSH Secure Shell File Transfer Upload Download 1 January 2011 [email protected] 39 Web Log (Blog), Video Log (Vlog), and Podcasting Web log (blog) Web site that people create and use to write about their observations, experiences, and feelings on a wide range of topics Podcast Audio broadcast over the Internet An audio blog 1 January 2011 [email protected] 4040 Usenet and Newsgroups Usenet Uses e-mail to provide a centralized news service Topic are called newsgroups Protocol that describes how groups of messages can be stored on and sent between computers 1 January 2011 [email protected] 4141 1 January 2011 [email protected] 42 Chat Rooms Enable two or more people to engage in interactive “conversations” over the Internet Internet Relay Chat (IRC) Requires participants to type their conversation rather than speak 1 January 2011 [email protected] 4343 Internet Phone and Videoconferencing Services Internet phone service Voice-over-IP (VoIP) technology Relatively inexpensive, especially for international calls Network managers can route phone calls and fax transmissions over the same network they use for data Internet videoconferencing Supports both voice and visual communications 1 January 2011 [email protected] 4444 Social Networks Facebook The U.S. intelligence community Provides an application development platform so that technically proficient members can create applications to run within Facebook Is adopting social networking to share information among operatives and analysts Twitter Allows members to report on what they are doing throughout the day 1 January 2011 [email protected] 45 Facebook Accounts 1 January 2011 [email protected] 46 Media Sharing YouTube Allows members to post homemade video content Flickr Allows members to upload photos to their own personal online photo album and choose photos to share with the community 1 January 2011 [email protected] 47 Social Bookmarking Purpose To provide a view of the most popular Web sites, videos, blog articles, or other Web content at any given moment Popular social bookmarking sites del.icio.us Digg 1 January 2011 [email protected] 48 Content Streaming Method for transferring multimedia files, radio broadcasts, and other content over the Internet Enables users to browse large files in real time 1 January 2011 [email protected] 49 Shopping on the Web Amazon Shorts Has stories that vary in length from 2,000 to 10,000 words Bot (intelligent agent) Software tool that searches the Web for information, products, or prices 1 January 2011 [email protected] 5050 Web Auctions Web auction eBay A way to connect buyers and sellers Popular auction site Easy to use and includes thousands of products and services in many categories Auction sites Cannot always determine whether the people and companies listing products and services are legitimate 1 January 2011 [email protected] 5151 Music, Radio, Video, and TV on the Internet Radio broadcasts are now available on the Internet Video and TV are also becoming available Internet Protocol Television (IPTV) protocol Used to put TV programming on the Internet 1 January 2011 [email protected] 5252 E-Books and Audio Books Digital books, both in text and audio form Are growing in popularity thanks to appealing devices and services Audio books Have become more popular due to the popularity of the iPod and services like audible.com 1 January 2011 [email protected] 53 Office on the Web Internet office Web site that contains files, phone numbers, e-mail addresses, an appointment calendar, and more Allows your desktop computer, phone books, appointment schedulers, and other important information to be with you wherever you are 1 January 2011 [email protected] 5454 Other Internet Services and Applications Internet Can provide critical information during times of disaster Can be used to translate words, sentences, or complete documents from one language into another Facilitates distance learning, which has dramatically increased in the last several years 1 January 2011 [email protected] 5555 Intranets and Extranets Intranet Extranet Internal corporate network built using Internet and World Wide Web standards and technologies Network that links selected resources of the intranet of a company with its customers, suppliers, or other business partners Virtual private network (VPN) Secure connection between two points on the Internet 1 January 2011 [email protected] 5656 Intranets and Extranets 1 January 2011 [email protected] 57 Net Issues Management issues Service and speed issues ประเด็น Preventing attacks Keeping up with Internet traffic and traffic on company intranets Privacy, fraud, security, and unauthorized Internet sites People and companies are reluctant to embrace the Internet unless these issues are successfully addressed 1 January 2011 [email protected] 5858 Summary The Internet started with ARPANET Internet Protocol (IP) Transmission Control Protocol (TCP) The set of conventions used to pass packets from one host to another Other protocol used with IP The Web Collection of tens of millions of servers that work together as one in an Internet service 1 January 2011 [email protected] 5959 Summary (continued) Hypertext Markup Language (HTML) Internet and Web applications include: Web browsers, e-mail, Telnet, FTP, Web logs (blogs), podcasts, Usenet and newsgroups, chat rooms Telnet and SSH Standard page description language for Web pages Enable you to log on to remote computers Online social networks Provide Web-based tools for users to share information about themselves with others 1 January 2011 [email protected] 6060 Summary (continued) Intranet Extranet Internal corporate network built using Internet and World Wide Web standards and products Network that links selected resources of the intranet of a company with its customers, suppliers, or other business partners Management issues, service, and speed affect all networks 1 January 2011 [email protected] 6161 Questions? 1 January 2011 [email protected] 62 Assignment#9 9a. โปรโตคอล (Protocol) นันคื ้ ออะไร โปรโตคอลหลักของ อินเทอร์ เน็ตคืออะไร ทำหน้ ำที่อะไร 9b. เว็บเบรำเซอร์ คืออะไร เมื่อเรำเรี ยกดูเว็บเพจ เว็บเบรำเซอร์ ทำอะไร อย่ำงไร 1 January 2011 [email protected] 63 ส วั ส ดี 1 January 2011 [email protected] 64