Chapter 2

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Chapter 2:
Technology Infrastructure: The
Internet and the World Wide Web
The Internet and the World Wide Web
 Computer network
 Any technology that allows
people to connect computers to
each other
 The Internet
 A large system of
interconnected computer
networks spanning the globe
 World Wide Web
 A subset of computers on the
Internet
Growth …
The Internet
 Internet
 Interconnected network of thousands of networks and millions of
computers
 World Wide Web (WWW)
 Provides access to over one billion Web pages
 Key concepts
 Packet switching
 TCP/IP
 Client Server Computing
The Internet: Key Technology Concepts
 Packet switching

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slices digital messages into packets
sends packets along different
communication paths reassembles packets
once at their destination
Routers
 Special-purpose computers that
interconnect the computer networks that
make up the Internet
 Routing algorithm
 Computer program that ensures
packets take the best available path
toward their destination
The Internet: Key Technology Concepts
 Protocol
 A set of rules for formatting,
ordering, compressing, and error
checking messages
 TCP (Transmission Control Protocol)
 establishes the connections among
sending and receiving Web
computers,
 handles the assembly of packets at
point of transmission, & reassembly
at receiving end
 IP (Internet Protocol)
 provides the Internet’s addressing
scheme
IP Addresses
 Internet addresses expressed as 32-bit numbers appear as 201.61.186.227 -- each
of the four numbers range from 0 to 255 allowing for up to 4 billion addresses
 In the next generation IP 128-bit addresses will allow about one quadtrillion
addresses
Domain Names
 A domain name is a set of words assigned to a specific IP address
 Internet Corporation for Assigned Names and Numbers (ICANN)
 Responsible for managing domain names and coordinating them with IP
address registrars
Client/Server Computing
 Client/server
 Computing model where powerful
personal computers are connected
together in a network with one or more
servers.
 Client
 Powerful personal computer that is
part of a network. Capable of
displaying rich graphics, storing large
files, and processing graphics and
sound files.
 Server
 Networked computer dedicated to
common functions needed by client
machines -- storing files, software
applications, utility programs, and
printers.
Internet I Network Architecture
Internet NAPS and MAES
ISP Service Level Choices
Internet II Technology Environment
 A consortium of more than 180
universities, government agencies, and
private businesses that are collaborating
to find ways to make the Internet more
efficient
 Goals
 Create a leading edge network
capability for the national research
community.
 Enable revolutionary Internet
applications.
 Ensure the rapid transfer of new
network services and applications to
the broader Internet community.
 Next Generation Internet (NGI)
 initiated and sponsored by the federal
government
 Focus: developing advanced
applications and networking
capabilities needed by
government agencies
 Fiber Optics and Bandwidth Explosion
 replacing older transmission lines
with fiber-optic cable
 improving fiber-optic-based
communications technology &
fiber-optic switching speeds
Bandwidth Demand of Various Web
Applications
Wireless Web and 3G Technologies
 General Packet Radio Switching
 next generation technology carries data in packets, just like the Internet,
but over radio frequencies that make wireless communications possible
 Wireless Application Protocol
 relatively new protocol -- supports virtually any wireless network and is
supported by every operating system
 Wireless Markup Language
 programming language for devices using WAP
Markup Languages and the Web
Individual Exercise




Search “XML Overview” using Google
Click on the first reference: “XML Tutorial: Overview”
Click on the first reference “HTML and XML”
Browse through the presentation




What are attributes of HTML?
What are attributes of XML?
How do they differ?
What benefits does XML provide?
Internet II and E-commerce: Emerging Features and Services



IP Telephony
 Uses VOIP & Internet’s packet-switched
network to transmit voice & other forms
of audio communication
Digital Libraries
 ASP distributes application software,
multimedia, and other services on a fee
basis by
Distributed Storage
 ASPs can assist both in processing data,
storing it, & dispersing it to multiple
servers
Internet II and E-commerce: Emerging Features and Services
 Distance Learning
 one the biggest education initiatives
in recent years, provides courses and
degree programs online
 Digital Video
 deliver better-than-broadcast
quality video over the Internet on
demand
 Video Teleconferencing
 significantly reduce the cost,
workers share information that
involves either and image or audio
component
 Tele-immersion
 Merges virtual reality and video
conferencing -- participants can see
each other and collaborate on visual
projects
 M-commerce Applications
 combines voice, data, images, audio,
and video on one wireless device
Exercise: For your group’s topic, “research” the topic and present a brief overview of the key issues
concerning the topic that you found
 Distance Learning
 one the biggest education
initiatives in recent years,
provides courses and degree
programs online
 Digital Video deliver betterthan-broadcast quality video
over the Internet on demand
 Video Teleconferencing
 significantly reduce the cost,
workers share information that
involves either and image or
audio component
 Tele-immersion
 Merges virtual reality and video
conferencing -- participants can see
each other and collaborate on visual
projects
 M-commerce Applications
 combines voice, data, images, audio,
and video on one wireless device
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