1. The World Wide Web and the Internet MIS XLM.B Jack G. Zheng June 20 th 2005

2. 2 Overview The Internet technologies World Wide Web Searching on the Web Connecting to the Internet

3. 3 Introduction The Internet a world-wide network of networks and computers based on IP (Internet Protocol) World Wide Web, or Web An Internet application based on HTTP protocol

4. The Internet Image source: www.wagoneers.com

5. 5 First Questions about the Internet What is the Internet? Who manages/controls/coordinates the Internet? How did it come into being? What can we do on the Internet? How does it work? Internet backbone Servers Protocols

6. 6 The Internet Backbone How are computers connected world wide? The Internet Backbone Major sets of connections Network access point (NAP): a point on the Internet where several connections converge Who operates the Internet backbone? Network service provider (NSP): Also called backbone operator Usually provide services to ISPs MCI, AT&T, … (see more here)see more here

7. 7 Internet Service Provider ISP is a company that provides individuals, organizations, and businesses access to the Internet Biggest ISP 1 AOL: 23.4M users MSN: 8.7M (2003) United Online (including NetZero and Juno): 6.8M Comcast: 6.0M EarthLink: 5.2M GSU? GSU wireless access http://wireless.gsu.eduhttp://wireless.gsu.edu 1 Data from: http://www.isp-planet.com/research/rankings/usa_h.html (2004)http://www.isp-planet.com/research/rankings/usa_h.html

8. 8 Internet Servers and Applications Internet server computer provides information and services on the Internet Web server Mail server FTP (file transfer protocol) server IRC (Internet Relay Chat) server Router Connects different networks (routing) Client computer

9. 9 Internet Communication Protocols Communication protocol is a set of rules and format to transfer information TCP/IP (transmission control protocol/Internet protocol) The featured protocol of the Internet Application protocols HTTP (hypertext transfer protocol) FTP (file transfer protocol)

10. 10 Internet: Putting It Altogether Adapted from figure B.8 on page 114 Internet backbone

11. World Wide Web Total Sites Across All Domains September 1995 - June 2005 Source: http://news.netcraft.comhttp://news.netcraft.com

12. 12 Understanding WWW Some history Tim Berners-Lee, the creator of the Web (1989) Read more http://www.w3.org/People/Berners-Lee/ http://www.slac.stanford.edu/history/earlyweb/ Three most important things for Web HTML (hypertext markup language) HTTP (hypertext transfer protocol) URL or URI (uniform resource locator)

13. 13 Web Common Terms Link (hyperlink) Web site vs. web site address Website is a specific location on the web, consisting of a group of web pages or web applications Website address is a name that identifies a specific website Web page vs. URL Webpage is a specific file (usually in HTML) in a website URL (Uniform Resource Locator) is an address for a specific web page or file on the web !Domain (name) identifies a specific place (computer) on the Internet

14. 14 Domain Name [Domain Name System (DNS)] A system that provides the mapping between IP and domain name Internet Corporation For Assigned Names and Numbers (ICANN) Top-level domains: 2 letter country code: us, uk, jp, ca, au, cn, … Created in 1980.com – commercial or for-profit business.net – Internet administrative organization.org – professional or non-profit organization.edu – educational institution.gov – U.S. government agency.int – international treaties organization.mil – U.S. military organization Created in 2000 coop, info, biz, museum, name, pro, aero

15. 15 Understanding URL http://www2.gsu.edu/~wwwaux/panthercard/index.htm The complete link is a URL http is the protocol www2.gsu.edu is the domain www2.gsu.edu/~wwwaux/ is the web site (of GSU Auxiliary and Support Services) index.htm is the actual file (web page).

16. 16 Web Server Web server Web server hosts websites, providing files and applications (services) Market Share for Top Servers Across All Domains. Source: netcraft.com Web applications software applications delivered through web technologies (HTTP, HTML, web server, browser,...) Examples Searching Shopping News Forum Survey BLog …

17. 17 Web Client (Browser) Web browser software (web client) Provides a web interface for users It understands HTML, scripts and works with other plug-ins Web browser products: WorldWideWeb Internet Explorer (Microsoft) Mozilla (formerly Netscape Navigator) Firefox

18. 18 Searching on the Web Two major ways to seek information on the web Searching: using a true search engine Navigating: using structures, such as directories, site maps, indexes Search engine A web application that helps you find web pages and websites with the information and/or services you want Directory search engine Yahoo! Directory Google Directory (open directory http://dmoz.org/)http://dmoz.org/ True search engine

19. 19 True Search Engine True search engine uses software agent (web crawler) technologies to search the Web and put them into databases; then users search by key words or other criteriakey words Top 4 providers 1 Google (112m searches per day) AOL (93) Yahoo (42) MSN (32) Source: businessweek June 11, 2004 1 SIMS study how much information 2003

20. 20 Connecting To The Internet Connection type: Dial-up, DSL, Cable? How much do you pay? How fast is the connection? What devices do I need? Broadband connection accounts for more than 50% in 2004, according to Clickz.com broadband statistics

21. 21 Home Networking [Home networking and Internet sharing] Modem (Wireless) router Network card Image adapted from D-Link

22. 22 Summary Web is one of the many applications on the Internet The Internet is built on the Internet backbone, Internet Servers and communication protocols Understand web common terms Domain URL Web site (address) Web page Search engines

23. 23 Web Resources Histories http://livinginternet.com http://www.netvalley.com/intvalconcl.html About search engine http://searchenginewatch.com/ How does DNS work http://www.howstuffworks.com/dns.htm Internet access information http://www.dslreports.com