The Internet

1
The Internet

• MCC - CIS105

2
Topics

• Briefly describe the history of the Internet
• Describe generally what an Internet service
  provider does
• Describe various types techniques used by
  Internet search sites
• Describe the various types of e-commerce
• Describe how advertising is done on the Internet
• Describe what an intranet is and how a business
  uses it

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The Internet and Services

• The Internet is a worldwide collection of
  networks used to provide services such as
• World Wide Web (WWW) Websites
• Email, Instant Messaging (IM)
• Telephony Voice over IP (VoIP)
• Social network, newsgroups, discussion boards
• File Transfer Protocol (FTP)
• E-commerce business transactions
• For an overview of Making Use of the Web, see
  pages 116-131 in the textbook Discovering
  Computers 2008.

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Internet - many networks connected together
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Quick Time Line

• 1969 - ARPANET (Advanced Research Project Agency)
• Government sponsored the creation of a network.
• Scientists and military shared information.
• Network needed to provide alternative paths in
  case part of the network was destroyed (war).
• 1972 - E-mail capability added
• 1973 The internet went international
• 1986 - National Science Foundation (NFS)
  connected its large network, NSFnet,to ARPANET.
• 1995 NFS transferred service providing role
  to private companies.

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Number of Users

• 2002 567 million users
• 2003 780 million users after 34 years
  (1969-2003) Compare to
• 2005 US population 295 million
• Telephone took 91 years to reach 100 million
  users.
• Television took 54 years to reach 100 million
  users.

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Number of Sites

• Another way to measure the growth is by the
  number websites
• 1969 4 sites
• 1971 20 sites
• 1979 200 sites
• 1989 100,000 sites
• 2000 72,000,000 sites
• Why did it grow so much faster between 1989 and
  2000?
• One reason was the number Personal Computers
  grew.
• The other was the introduction of the Graphical
  Browser

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Graphical Web Browser

• A Browser is software used to navigate on the
  Internet (Internet Explorer, Firefox, etc.).
• 1990 Dr. Berners-Lee from Geneva wanted to make
  the links from one website to another more
  dynamic and easy using hyperlinks .
• HyperText Markup Language (HTML) is the language
  used to create web pages.
• He described the links like a spiders web.
• Hence the name World Wide Web (WWW).
• 1992 Marc Andreessen, college student at
  University of Illinois and Eric J. Bina developed
  Mosaic first graphical web browser for multiple
  platforms.
• Graphical browser with hyperlinks and graphics.
• 1993 Andreessen and Ken McCarthy developed
  Netscape.

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Internet Service Provider (ISP)

• An Internet Service Provider (ISP) provides the
  server computer and connection software for
  companies and individuals to connect to the
  Internet from their home or business (Earthlink,
  Qwest, Cox, Hughes, etc).
• Users at home need a modem to connect to their
  ISP.
• Dialup over phone lines
• DSL (digital subscriber line) - over phone lines
• Cable coaxial and/or fiber optic
• Fixed Wireless slow to catch on Tempe,
  Chandler
• Mobile Wireless cell phones, PDAs, laptops
• Satellite - Two modems (uplink and downlink)

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TCP / IP

• TCP/IP is the communication standard (protocol)
  used on the Internet.
• Transmission Control Protocol (TCP) determines
  how messages are managed
• A message sent over the Internet is divided into
  uniformly sized packets.
• Each packet is labeled with its destination
  address.
• At the destination the message is reassembled
  using the sequencing information.
• Internet Protocol (IP) determines how
  communications software and equipment transport
  messages.

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Uniform Resource Locator (URL)

• A URL is the complete and unique address of a
  Web page.
• Web page URL begins with http
• HyperText Transfer Protocol
• Domain name address of sites host computer
• Last part of domain name is called a top-level
  domain
• Identifies country and/or purpose of organization
• URL may include folder and specific filename.

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Registering a Domain Name

• Internet Corporation for Assigned Names and
  Numbers (ICANN) is the group that assigns and
  controls top-level domain names.
• Outside the United States, the domain name also
  includes a country code.
• For example - Australia www.philips.com.au

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Domain Name mapped to IP Address

• An IP address is a unique Numeric Address for
  each device on the Internet.
• An IP address consists of four groups of numbers
  separated with a period. IP Address
  http//64.233.167.99/
• Domain names are mapped to IP Addresses by a
  Domain Name Server (DNS).
• Domain names are meaningful and easier to
  remember for users. Domain
  http//www.google.com/
• Search for IP Addresses (use WhoIs Lookup)
  http//www.dnsstuff.com/
• Error 404 If domain name is not found in DNS.

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User called Helpdesk because their Internet
connection was not working.

• Turns out the user had set the invalid URL as
  their homepage, so the error page was displayed
  every time they opened their browser ?.

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Web Browser Limitation

• Browsers can process and display several formats
  such as HTML, gif, jpeg, JavaScript, etc.
• However, browsers cannot handle everything.
• Functionally is increased by using
• Plug-ins
• Helpers
• Web Programming
• See next few slides

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Plug-ins / Helpers

• Software that increases browser functionality
• Most downloaded from their own Web sites
• Once downloaded and installed, it appears as if
  the browser can handle the new features.
• The features are being processed by the plug-ins.
• Most enhance a sites audio/visual experience
• Flash and QuickTime Players permit viewing sites
  that include quality animation
• Adobe Acrobat Reader displays and prints
  documents created in Portable Document Format
  (PDF) format

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Web Page Programs

• Small programs can be downloaded to run in your
  browser
• Allow dynamic interaction and dynamic data
• Scripting languages (Client Side)
• Instructions to be interpreted and executed by
  your browser
• JavaScript and VBScript are most common
• Programming Languages (Client and Server Side)
• Java applets and ActiveX controls are most common
• Scripting languages that can call programs stored
  on the server include ASP, JSP, PHP, Perl, and
  others.
• May require additional software be installed such
  as Java Runtime Environment (JRE)
• Cookies information that a program stores on
  your hard disk so that it can remember something
  about you or your process at a later time.

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Searching the Internet

• Search Engine
• Lets a user specify simple or complex search
  criteria.
• Search engine then searches the entries in its
  database and returns a list of sites that matches
  the criteria.
• Uses spider software to build database.
• Spiders crawl throughout websites collecting
  information can even find hidden files.
• Trivia - Google was supposed to be Googol, the
  number 1 followed by 100 zeros
• Internet directory list is developed by humans
  rather than a spider, so entries are very
  selective (yellowpages).
• www.mc.maricopa.edu/dept/d07/cis105/searchengines.
  html

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Evaluating the Information

• Author
• Sources
• Server (who provides)
• Objectivity (balanced?)

• Purpose
• Accuracy
• Currency

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Email

• Basic Electronic Mail (email) needs
• A server with email services
• Users need an account
• Need a client application to access the server
• SPAM is unsolicited e-mail.
• The term spam is said to derive from a famous
  Monty Python sketch.
• SPAM is a trademarked Hormel meat product.
• Phishing is e-mail fraud where the perpetrator
  sends out legitimate-looking e-mails that appear
  to come from well known and trustworthy Web sites
  in an attempt to gather personal and financial
  information from the recipient (see next slide).

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Phishing Examples
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Other Communication Services

• Social Networks myspace, facebook
• NewsGroups allows posting and reading of
  messages to a group for everyone to read
  (discussion board).
• IRC Internet Relay Chat
• Text Chatting in Real Time to a group, like a
  party line
• Instant Messaging to one person
• Internet Telephony Real-Time Voice and
  VideoVoIP Voice over IP (Internet Protocol)
• Internet Phone Services (Vonage)

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File Transfer Protocol (FTP)

• Allows for upload and download of files.
• Anonymous FTP
• No username or password required.
• Uploading will most likely require a username and
  password.
• Some files are compressed into an archive using a
  program like WinZip, so the files need to be
  expanded or extracted after downloading.
• Self-extracting is an executable that is
  double-clicked to begin file extraction.
• If not self-extracting, will need a compatible
  program to extract files.

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Homepage / Portal

• Homepage is the first page displayed when the
  browser is opened
• A portal is a website that is supposed to be set
  as your homepage.
• Webpage can be personalized so information you
  are interested in is displayed stock market,
  sports, weather
• May advertise referrals to businesses
• Yahoo, Google, MySpace, etc.

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Internet Advertising

• Many advertisements on Web sites are banner ads
• Pop-over ads open a new window on top of your
  current window
• Pop-under ads open a new window underneath your
  current window
• All this advertising is to increase electronic
  commerce

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Electronic Commerce

• B2B (Business to Business)
• B2C (Business to Consumer)
• C2C (Consumer to Consumer)
• Ebay.com watch for fraud
• CraigsList.org Free classified ads
• Payments SSL Secure Sockets Layer
• ePal is a 3rd party that handles payments.
• Internet Taxes Freedom Act
• No sales tax on out-of-state sales
• But usually need to pay shipping
• Privacy companies must provide you their
  privacy policy.

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Intranets Extranets

• An Intranet is a private Internet-like network.
• Uses the same technology as used for an Internet
  site.
• Internal only computers on the same network may
  access services ie Employee Information
• Extranets allow selected customers and suppliers
  to have access to a companys intranet.
• EDI Electronic Data Interchange
• Standard format to exchange data (ie College
  transcripts, financial data)
• Can usually identify an Intranet/Extranet when a
  username and password is required to enter.
• Access can be restricted using firewalls and IP
  addresses.
• Firewalls hardware and software

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Want to Learn More?

• CIS133DA Internet / Web Dev
• CIS235 e-commerce
• Certificate of Completion or Two-Year Degree in
  Web Technology.www.mc.maricopa.edu/dept/d07/deg
  rees.html