The Internet and the World Wide Web

1
The Internet and the World Wide Web
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What is the Internet?

• A Short History
• The Internet Today
• How the Internet Works
• Basic Internet Applications
• Specialized Apps

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What is the Internet? and Not
On-Line Providers
Dialup Access to Providers Computer Systems
Gateways
7 Million Computers Seamlessly Integrated via
60,000 Largely Private Networks
Gateways
UUCP Nets, FidoNets, BitNets, X400,...
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A Short History of the Internet

• 1964Paul Baran (RAND Corp.) proposes a
  loosely-coupled, robust network
• 1969ARPANET formed as a four-node network (UCLA,
  SRI, UCSB, and U of Utah-Salt Lake City)
• 1974Kahn and Cerf head TCP/IP project
• 1980CSNET added to ARPANET
• 1986NSF forms NSFNET

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A Short History of the Internet

• 1987NSFNET backbone expands the Internet
  worldwide
• 1989CERN launches WWW project
• 1990ARPANET decommissioned
• 1992Internet Society formed
• 1993NCSA Mosaic GUI for WWW
• 1995NSFNET decomissioned

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The Internet Today
Connectivity Worldwide
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The Internet Today
124 Million Internet Hosts
124 Million Internet Hosts
hosts
hosts
NOW
Historical Values
Historical Values
Projected Values
Projected Values
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How is the Internet Used?
IRC
DNS
1
APPLICATIONS
2
Gopher
3
Telnet

• FTP is the top application (based on packets
  transferred)
• WWW is a close second

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Mail
1,075 Other
5
Services
29
NewsNet
9
WWW
20
FileTransfer
28
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How is the Internet Used?

• information sharing
• global collaboration
• distance education
• software distribution
• scientific research
• product development
• public service
• marketing sales
• customer support
• professional development
• entertainment

some of its many uses...
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How the Internet Works

• Internet is a packet-switched network
• DATAGRAMs are packets of data that also contain
  addressing information
• TCP/IP are protocols (standards) for how
  datagrams are packaged and delivered
• IP address is a number that signifies the address
  of an Internet host
• Domain names are pseudonyms for IP addresses

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How the Internet Works

• Gateways and Routers transmit datagrams across
  the Internet
• Client/Server applications add functionality to
  the Internet

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Basic Internet Applications

• ELECTRONIC MAIL (EMAIL)asynchronous
  communications
• mail client
• mail server

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Basic Internet Applications

• REMOTE LOGINS (TELNET)synchronous 2-way
  communications
• local host
• remote host

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Basic Internet Applications

• FILE TRANSFER PROTOCOL (FTP)exchanging data and
  programs between systems
• anonymous ftp

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Specialized Internet Apps

• ARCHIEsearching anonymous ftp servers for files
  by name
• GOPHERorganizing data and connections as
  hypertext
• CHATlive group conversations
• MUDs MOOsgroup interactions in a virtual
  environment