The World Wide Web and the Internet

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					The World Wide Web
and the Internet

             Jack G. Zheng
             June 20th 2005

 The Internet technologies
 World Wide Web
 Searching on the Web
 Connecting to the Internet


 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

The Internet

               Image source:
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

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)

       Internet Service Provider
        ISP is a company that provides individuals, organizations,
             and businesses access to the Internet

        Biggest ISP1
                    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

1   Data from: (2004)
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

Internet Communication Protocols

 Communication protocol is a set of rules and
  format to transfer information

 TCP/IP (transmission control protocol/Internet
    The featured protocol of the Internet

 Application protocols
    HTTP (hypertext transfer protocol)
    FTP (file transfer protocol)

     Internet: Putting It Altogether
                                      Internet backbone

Adapted from figure B.8 on page 114                       10
     World Wide Web

Total Sites Across All Domains September 1995 - June 2005

    Understanding WWW

 Some history
    Tim Berners-Lee, the creator of the Web (1989)
    Read more

 Three most important things for Web
    HTML (hypertext markup language)
    HTTP (hypertext transfer protocol)
    URL or URI (uniform resource locator)

    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

     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

    Understanding URL

 The complete link is a URL
 “http” is the protocol
 “” is the domain
 “” is the web site
  (of GSU Auxiliary and Support Services)
 “index.htm” is the actual file (web page).
    Web Server
 Web server
    Web server hosts websites, providing files and applications

 Web applications
    software applications
     delivered through web
     technologies (HTTP,
     HTML, web server,
     browser, ...)
    Examples
          Searching
          Shopping
          News
          Forum
          Survey                 Market Share for Top Servers Across All
          BLog                       Domains. Source:
          …
    Web Client (Browser)

 Web browser software (web client)
    Provides a web interface for users
    It understands HTML, scripts and works with other

 Web browser products:
      WorldWideWeb
      Internet Explorer (Microsoft)
      Mozilla (formerly Netscape Navigator)
      Firefox

    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
    True search engine

            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 criteria

     Top 4 providers1
            Google (112m searches
             per day)
            AOL (93)
            Yahoo (42)
            MSN (32)
                                             Source: businessweek June 11, 2004

1   SIMS study “how much information 2003”
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 broadband statistics

    Home Networking

     [Home networking and Internet sharing]
             Modem
             (Wireless) router
             Network card

Image adapted from D-Link
 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

Web Resources
 Histories

 About search engine

 How does DNS work

 Internet access information


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