Transcript C04.Internetx - SIUE Computer Science

Internet
The Internet is the world’s largest public
computer network, a network of networks
that provides a vast array of services to
individuals, businesses, and organizations
around the world.
In this section:
• Internet Technologies
• Web Technologies
• Web Applications
1958 – DoD: ARPA, NASA
1969 – ARPANET
1993 – World Wide Web
Links:
The Internet
Concepts > Internet
Internet
Technologies
Many different Internet technologies work
together to provide information and services
over the Internet, including a variety of
protocols, hardware, and software.
In this section:
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Internet Backbone
TCP/IP
Internet Service Provider (ISP)
Client/Server
Peer-to-Peer
Concepts > Internet > Internet Technologies
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Router
Domain Name System (DNS)
Port
Voice over IP (VoIP)
Internet2
Internet Backbone
Submarine fiber optic cables such as this
make up the portion of the Internet
backbone that connects countries around
the world.
Courtesy of Tyco Electronics SubSea Communications
The Internet backbone
refers to the main Internet
pathways and connections,
made up of the many
national and international
communication networks that
are owned by major telecom
companies, such as Verizon,
AT&T, and Sprint - the same
companies and networks that
provide telephone service –
mostly fiber-optic cables.
Concepts > Internet > Internet Technologies > Internet Backbone
TCP/IP
The protocols on which the
Internet is based are the
Transmission Control Protocol
(TCP) and Internet Protocol
(IP); together referred to as
TCP/IP.
Internet applications divide up
information, such as an email
messages, into small packets to
make efficient use of the network.
Upon arriving at their destination, the
packets are reconstructed into the
original message.
Concepts > Internet > Internet Technologies > TCP/IP
Expanding the Internet
Links:
Expanding the Internet: From IPv4 to IPv6
IPv4 & IPv6: A Short Guide
Concepts > Internet > Internet Technologies > TCP/IP
Internet Service Provider
A company that provides individuals
and organizations with access to the
Internet is called an Internet service
provider (ISP).
ISPs charge a monthly fee to Internet
users and provide devices, such as
modems, by which the user can
connect to the Internet.
Concepts > Internet > Internet Technologies > Internet Service Provider
Client/Server
Client/server is a network
architecture in which one computer
or program (the client) makes a
service request from another
computer or program (the server),
which provides the service.
Concepts > Internet > Internet Technologies > Client/Server
Peer-to-Peer
Peer-to-peer (P2P) is a network
architecture that does not utilize a
central server, but facilitates
communication directly between
clients with computers acting as
both client and server.
Concepts > Internet > Internet Technologies > P2P
Peer to Peer Filesharing
Links:
Peer to Peer Filesharing
Concepts > Internet > Internet Technologies > P2P
Router
Although routers play a crucial role on the
Internet backbone, they also are used on
smaller networks. Routers are used on
business and home networks to allow
computers on the network to communicate.
Concepts > Internet > Internet Technologies > Router
A router is a
network device
that manages
network traffic by
evaluating
messages and
routing them over
the fastest path
to their
destination.
Voice over IP (VoIP)
Voice over IP (VoIP) refers to technologies that
support voice communications using the Internet
Protocol over data networks.
This VoIP phone combines
voice, video, and text
communications.
Links:
Skype
Concepts > Internet > Internet Technologies > VoIP
Cisco Unified Communications
Links:
Cisco Unified Communications
Concepts > Internet > Internet Technologies > VoIP
Web
Technologies
1) Hyperlinks
2) Protocols (HTTP) – W3C & Berners-Lee
3) Tools (HTML)
The Web, short for World Wide Web, is an
Internet service that provides convenient
access to information and services through
hyperlinks.
In this section:
• Web Browser
• Web Server
• URL
• HTML
• XML
• CSS
• Web Development
Software
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Cookie
Plug-in
Web Programming
RSS
Links:
Tim Berners-Lee on the next Web
Concepts > Internet > Web Technologies
Web Browser
A Web client, usually called a
Web browser, such as
Internet Explorer, Safari, and
Firefox, is used to request Web
pages from Web servers,
interpret the HTML code in the
Web page that is delivered,
and display it onscreen.
Concepts > Internet > Web Technologies > Web Browser
What is a browser?
Links:
What is a browser?
Concepts > Internet > Web Technologies > Web Browser
Web Server
The term Web server refers to
software that fulfills Web page
requests from Web clients, and the
computers that run such software.
Web hosting companies provide
Web service and Web storage
services
to
individuals
and
businesses for an annual fee.
Concepts > Internet > Web Technologies > Web Server
URL
http://
www.
cengage.com/
coursetechnology/
index.html
Protocol
Web server
Domain name
Location on server
Requested file
http://www.cengage.com/coursetechnology/index.html
Top-Level Domains
.com
.net
.biz
.gov
.edu
.me
.org
.mobi
A Uniform Resource Locator, more commonly called a
URL, acts as a Web page address, incorporating the domain
name of the Web server and the location of the Web page
file on the server.
Links:
Go Daddy
Concepts > Internet > Web Technologies > URL
HTML
Hypertext Markup Language (HTML) is the
primary markup language used to specify the
formatting of a Web page.
Concepts > Internet > Web Technologies > HTML
XML
XML (Extensible Markup
Language) provides a method for
describing and classifying Internetdelivered data so that it is easier to
organize and manage.
XML code used to
catalogue a collection of
CDs
Concepts > Internet > Web Technologies > XML
CSS
Cascading Style Sheets or CSS
allows easy application of visual
styles for fonts, colors, layout, and
other page attributes to create a
visual theme for Web pages and
sites.
Provides a consistent
design and appearance
across multiple pages
on a Web site.
Links:
CSS Zen Garden
Concepts > Internet > Web Technologies > CSS
Web Development Software
Web development software
allows developers to create Web
pages more easily using a wordprocessing-style environment and
automating complex coding
activities.
WYSIWYG (pronounced “wizziewig”) implies that the Web page you
design with the Web development
software will look the same when
published on the Web.
Links:
Weebly
Concepts > Internet > Web Technologies > Web Development Software
Cookie
A cookie, sometimes called an
HTTP cookie, is a small text file
placed on a user’s computer by a
Web server in order to identify the
user whenever he or she returns to
visit a Web site.
Cookie files can contain data or
perhaps a unique identifier that is
used to look up your personal profile
in a database on the server.
Links:
Information about Cookies on Microsoft.com
How to manage cookies in Firefox Web browser
Concepts > Internet > Web Technologies > Cookie
Cookies 101
Links:
Cookies 101
Concepts > Internet > Web Technologies > Cookie
Plug-In
Flash Player, Acrobat Reader,
Java Runtime Environment, QuickTime,
RealPlayer, Windows Media Player
A plug-in, also called an
extension or add-on, works
with a Web browser to
offer extended services
such as audio players,
video, animation, 3D
graphics viewers, and
interactive media.
Links:
Concepts > Internet > Web Technologies > Plug-In
Internet Explorer Add-ons
Firefox Add-ons
Safari Add-ons
Really Simple Syndication (RSS)
Really Simple
Syndication, or RSS,
is a Web technology
used to automatically
deliver frequently
updated Web
content, such as
blogs, podcasts, and
news, in a
standardized fashion.
Concepts > Internet > Web Technologies > RSS
Google Reader
Links:
Google Reader
Concepts > Internet > Web Technologies > RSS
Web Applications
Internet and Web applications are varied
and many, assisting individuals,
businesses, and organizations with all
facets of life including education, news and
information sharing, communication, travel,
commerce, and entertainment.
In this section:
• Search Engine
• Portal
• Internet Communications
• Online Information
• Online News
Concepts > Internet > Web Applications
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Online Education
Online Travel
Maps and Geolocation
Online Employment
Support
• Online Music
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Online TV and Video
Online Games
Web 2.0
Social Media
Web 3.0
Search Engine
A search engine is a valuable software tool that enables users to
find information on the Web by specifying words that are key to their
topics of interest – keywords.
Links:
Concepts > Internet > Web Applications > Search Engine
Google
Microsoft Bing
Yahoo
Dogpile
Mahalo
Portal
A Web portal is a
Web page that
combines useful
information and links,
and acts as an entry
point to the Web – the
first page you open
when you begin
browsing the Web.
Links:
Concepts > Internet > Web Applications > Portal
MSN
iGoogle
My Yahoo!
About.com
my SIUE
Web 2.0
Web 2.0 refers to Web
resources that allow average
users to collaborate and
contribute to Web content,
and to the transition of the
Web from an information
resource to a computing
platform.
Concepts > Internet > Web Applications > Web 2.0
Evolution Web 1.0  2.0  3.0
Links:
Evolution Web 1.0, Web 2.0 to Web 3.0
Concepts > Internet > Web Applications > Web Evolution
Web 3.0
Web 3.0 refers to the next
major change that will take
place in Web technology, and
as such is speculation at this
point.
Amit Agrawal states
that Web 3.0 is,
among other things,
about the Semantic
Web and
personalization
(Wikipedia).
Concepts > Internet > Web Applications > Web 3.0
WWW in Plain English
Links:
World Wide Web in Plain English
Concepts > Internet > Recap
Discussion Questions
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We often hear about information “in the cloud.” How has this concept changed the
direction of the Internet?
Share ideas on how the “digital divide” can be addressed so that everyone has
access to technology and the Internet.
List Internet service providers (ISPs) in your local area and compare the services
they offer.
Explain the role of the Transmission Control Protocol/Internet Protocol (TCP/IP)
when you send information over the Internet.
What are some things to consider when choosing a domain name for your personal
Web site? Business Web site?
List the benefits and drawbacks to combining voice, video, and data
communications into one interface, such as Skype.
Describe what happens when you visit a Web site where cookie files are enabled.
Should you worry about the information collected by these files? Why or why not.
How would you choose between using a RSS feed or a blog to learn about current
events on the web?
Google and Bing are two of today’s most popular search engines. Explain how they
are different. Which do you prefer and why?
Concepts > Internet > Discussion Questions