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The Internet
& Emerging
Technologies
The Internet
The Internet
• Based upon the client/server model
• Connects over 20 million people in over 100
countries (figures available when the book was
written)
• The Internet, at its lowest levels, is only a set of
common protocols that allow data transport. Other
services and functions can and do reside anywhere
and everywhere on the network.
The Internet
• Network traffic is re-routed around network
transport and/or server failures
Basic Problems of the Internet
• Inadequate security given the sensitive and
proprietary nature of information that
people may want to communicate through
the network
• Technological challenges with one the biggest
being a lack of standards
• Lack of clarity on many legal issues
World Wide Web
• A set of standards for organizing and
accessing a vast array of resources via the
internet
• Information is presented as a series of
documents - “Web Pages”
• The series of pages is called the “Web Site”
• The opening page is called the “Home Page”
• Content can include text, images, video,
sound, etc.
Web Browsers
• An application program specifically designed
to allow users to access the “Web”
• Users utilize point-and-click techniques to
access hypertext links
• Most popular are Netscape Navigator and
Internet Explorer by Microsoft
• Bookmarks allow you to store URL’s for easy
retrieval
• Many search engines are available for
locating web sites
What is HTML ?
• HTML stands for Hypertext Markup Language.
HTML consists of standardized codes,or "tags",
that are used to define the structure of information
on a web page. HTML is used to prepare
documents for the World Wide Web. A web page is
single a unit of information, often called a
document, that is available on the World Wide
Web.
• HTML defines several aspects of a web page
including heading levels, bold, italics, images,
paragraph breaks and hypertext links to other
resources
What is HTML ?
• HTML can be compared to word processing.
The text in a word processed file can be
formatted in various ways. For example, a
heading can be bold and in larger font size
than the rest of the document. Also, specific
words can be italicized for emphasis.
• HTML is a way to define the formats of text
in a web page. However, it goes further by
also being able to define placement of
graphics and hypertext links
What is HTML ?
• HTML tags are used to define areas of a document
as having certain characteristics.
• The tags used in HTML usually consist of a code in
between two "wickets". These codes are called
container tags because the formatting described by
the tags affects only the text contained between the
tags.
• For example, <B> and </B> are the starting and
ending tags used to indicate an area as bold.
Therefore, the following markup will yield a
sentence with the word "hello" in bold.
– Only the word <B>hello</B> will be bold.
What is HTML ?
• HTML tags are used to define heading levels,
such as <H1> and </H1>. Heading levels can
go to <H6>, with each successive number
indicating a smaller heading size.
• Some other basic HTML tags are:
– <I> and </I> used to indicate italics
– <img src="name-of-picture"> used to place an
image in a document file
– <P> used to create a paragraph break
Java
• Developed by Sun Microsystems
• Java extends the capabilities of web pages to
allow for robust applications
• Extremely popular with internet-based
applications because it is platform independent
• Normally, programs that need access to
graphics, network services, the disk, even
RAM, use a function call provided as part
of the base-level operating system to do
so. But in Java, the built-in run-time called
a virtual machine provides all these basic
JAVA
• Java is interpreted. What this means is
that Java source code does not get
compiled directly to machine
instructions like C++ or FORTRAN does.
Instead Java’s source code gets
compiled to an intermediate form called
byte-codes.
• Java has built-in support for multithreaded programming. This is an
example of something added to Java
that C++ does not support.
JAVA
• Java has built-in support for network
programming. This comes in the form of
classes that can deal directly with sockets
so that connections to servers can be
opened.
• A software component is a pre-built piece of
encapsulated application code that can be
provided with other components and with
hand-written code to rapidly product custom
applications.
• Java components (JavaBeans) makes it
easy for a large number of vendors to create
How It Works
• Step 1: User Requests a Web Page
HTTP
Workstation
(running Browser)
Web Server
How It Works
• Step 2: Web Page containing Java
Applet is sent back
HTTP
HTTP
Workstation
(running Browser)
Web Server
How It Works
• Step 3: Java VM Starts on Workstation
JAVA
Workstation
(running Browser
With Java Plugin)
Application
Server
Web Server
How It Works
• Step 4: Applet Communicates With
Application Server
JAVA
IIOP
Workstation
(running Browser
With Java Plugin)
Application
Server
Web Server
How It Works
• Step 5: App Server Talks to Database
IIOP
JDBC
Database
Workstation
Application
Server
LDAP
Other Companies Using
Java Technologies
• Ernst & Young
– Developed a 100% Pure Java application, called
Auditor's Workstation (AWS)
– The tax department is now able to review audit
workpapers and otherwise participate in the audit
process from their client's site or wherever they may
be--without experiencing bandwidth limitations.
This enables Ernst & Young auditors to access this
mission-critical application and modify secure and
confidential data from remote locations over the
Internet.
Other Companies Using
JAVA Technologies
• Xerox
– The Xerox Problem Management (XPM)
application is a key resource in that internal process.
XPM is written in the Java language and is part of
the core problem-solving system used by internal
groups at Xerox to identify and effectively resolve
product design, component, or manufacturing
problems
Interesting Sites
• Vincinity MapBlast
– Allows you to drill down and locate addresses
and print maps down to the street level,
anywhere in the United States
– http://www.vicinity.com/yt.hm?CMD=FILL&FA
M=mapblast&SEC=start
• Switchboard
– Allows you to locate address and phone numbers
of anybody in the United States (listed numbers
only)
– You can also locate businesses
– http://www.switchboard.com/bin/cgiqa.dll
Interesting Sites
• http://quote.yahoo.com
–
–
–
–
Get latest market news and stock quotes
Chart stocks from 1 day to 5 years
Obtain latest news for any company
Locate symbols for any stock
• http://www.dljdirect.com/cgi/inet/qndigest.trn?selection=option_quote_dl
&option_symbols=y&symbol=ALTR
– Obtain option quotes for Puts and Calls
– Hard to find option quotes
• Silicon Investor Calendar
– http://www.techstocks.com/Calendar.html
– Calendar of earnings reporting and chat
Interesting Sites
• The MBA Page
– http://www.cob.ohio-state.edu/dept/fin/mba.htm
– Valuable information for all students
– Survival guide is excellent
• Roget's Thesaurus
• Personal Development Information
• Magazines
– USA Today http://www.usatoday.com
– Wall Street Journal
http://update.wsj.com
– http://www.businessweek.com/contents.htm
Interesting Sites
• Entertainment
– The Golf Web
• HTTP://www.golfweb.com
– The National Park Service
• HTTP://www.nps.gov
• Coverage of all national parks, what they offer, costs,
etc.
Other Emerging Technologies
• Cable Modems
– Your cable company becomes your ISP
– Coming to Henrico by years end
• Biometrics
– Our biological characteristics can be mapped
and digitized