Overview of Data Communications and Networking

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PART I
Overview of Data Communications and Networking
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Overview
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Chapters
Chapter 1 Introduction
Chapter 2 Network Models
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Chapter 1
Introduction
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1.1 Data Communication
Components Data Representation Direction of
Data Flow
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Figure 1.1 Five components of data
communication
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Figure 1.2 Simplex
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Figure 1.3 Half-duplex
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Figure 1.4 Full-duplex
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1.2 Networks
Distributed Processing Network
Criteria Physical Structures Categories of
Networks
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Figure 1.5 Point-to-point connection
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Figure 1.6 Multipoint connection
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Figure 1.7 Categories of topology
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Figure 1.8 Fully connected mesh topology (for
five devices)
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Figure 1.9 Star topology
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Figure 1.10 Bus topology
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Figure 1.11 Ring topology
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Figure 1.12 Categories of networks
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Figure 1.13 LAN
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Figure 1.13 LAN (Continued)
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Figure 1.14 MAN
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Figure 1.15 WAN
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1.3 The Internet
A Brief History The Internet Today
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Chronology of Internet Evolution (W. Stallings)

• 1996 ARPA packet-switching experiment
• 1969 First ARPANET nodes operational
• 1972 Distributed e-mail invented
• 1973 Non US computer linked to ARPANET
• 1975 ARPANET transitioned to Defense
  Communications Agency
• 1980 TCP/IP experiment began
• 1981 New host added every twenty days
• 1983 TCP/IP switchover complete

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Chronology of Internet Evolution continued (W.
Stallings)

• 1986 NSFnet backbone created
• 1990 ARPANET retired
• 1991 Gopher introduced
• 1991 WWW invented
• 1992 Mosaic introduced
• 1995 Internet backbone privatized
• 1996 OC-3 (155 Mbps) backbone built

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Growth of the Internet

• Exponential growth in the 1990s (Web technology
  is a major factor)
• More than 30-million computers were attached to
  the Internet in 1998
• Doubling the size every 9 to 12 month in the 1990s

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the original ARPANET design
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Growth of the ARPANET. (a) Dec. 1969. (b) July
1970.(c) March 1971. (d) April 1972. (e) Sept.
1972.
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The NSFNET backbone in 1988.
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Figure 1.16 Internet today
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1.4 Protocols and Standards
Protocols Standards Standards
Organizations Internet Standards
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Websites

• http//www.isoc.org/internet/history/
• http//www.zakon.org/robert/internet/timeline/
• http//www.nsrc.org/codes/bymap/ntlgy/
• (Internetology 1993-97, by continents, by date)
• http//www.w3.org/History.html (Web history)
• http//en.wikipedia.org/wiki/Internet_backbone
• http//www.nthelp.com/maps.htm (backbone maps)
• http//directory.google.com/Top/Computers/Internet
  /Organizations/Internet_Backbone/