Transcript Overview - Planet Lin

Overview
1-23-06
• Review the Internet and the World Wide
Web
• Learn about Web server administration
• Explore the common tasks and services
performed by administrators
• Web Programs and Databases
Review the Internet and the
World Wide Web
• The Internet is a worldwide network of networks
– Shares WAN used by the international
telecommunications network
– Uses TCP/IP Transmission Control Protocol
(TCP) and the Internet Protocol (IP)
• TCP/IP
– Using TCP/IP, applications on networked hosts can
create connections to one another, over which they
can exchange data. The protocol guarantees reliable
and in-order delivery of sender to receiver data.
Review the Internet and the
World Wide Web
• Where the Internet uses the HTTP (Hyper
Text Transport Protocol) protocol, it is
called the Web
– Web servers use HTTP to communicate
• The Internet is not centrally controlled
Review the Internet and the World
Wide Web
• HTML - Short for HyperText Markup Language, the
authoring language used to create documents on
the World Wide Web. HTML is similar to SGML,
although it is not a strict subset.
• HTML defines the structure and layout of a Web
document by using a variety of tags and attributes.
• There are hundreds of other tags used to format and
layout the information in a Web page. Tags are also
used to specify hypertext links. These allow Web
developers to direct users to other Web pages with
only a click of the mouse on either an image or
word(s)
Review the Internet and the
World Wide Web
• Internet had its origins in the 1960s
• In 1995 a high-speed backbone was
created
– Included 4 network access points (NAPs)
– There have been many more NAPs created
since then although much traffic is now routed
between large ISPs (Internet Service
Providers). ISPs agree on sharing traffic
through peering agreements.
History of the Internet: 1965
• Hypertext, a method of preparing text that
allows readers to choose their own
pathways through the material, is invented
by Ted Nelson.
• The underlined word represents a
hyperlink that lets the reader click and
jump to a new page.
• It takes almost 30 years to catch on.
History of the Internet: 1969
• The ARPANET is established by the
Advanced Research Projects Agency
(ARPA), connecting universities, the
military and defense contractors.
• In 1973, ARPA launches the Internetting
Project to explore the possibilities of
linking networks
History of the Internet: the 1970s
• 1976: UUCP (UNIX-to-UNIX CoPy) is developed
at AT&T Bell Labs and distributed with UNIX one
year later. The term generally refers to a suite of
computer programs and protocols allowing
remote execution of commands and transfer of
files, email and netnews between computers.
• 1979: USENET (the decentralized news group
network), based on UUCP, is created by Steve
Bellouin, Tom Truscott and Jim Ellis.
History of the Internet: the 1980s
• 1986: The NSFNET, created by the
National Science Foundation, is born,
providing a national network. To many
people, this becomes the true birth of the
Internet
• 1989: Quantum, formerly Q-Link online
service for Atari and Commodore users,
becomes AOL.
History of the Internet: 1991
• Hypertext browsing software is proposed
by Tim Berners-Lee, the inventor of the
World Wide Web.
• Information interconnected by hyperlinks is
called a web. The Web is a hypertext
system on a global scale.
• ANS, Advanced Network Systems, spins
off to the NSFNET and becomes the first
commercial ISP. Its mission is to foster
commercial and research networking
History of the Internet: 1992
• The Internet Society (ISOC) is founded,
incorporating the Internet Architecture
Board.
• The ISOC's primary function is to foster
international participation and cooperation
in Internet technologies. Membership is
open to all.
History of the Internet: 1993
• The U.S. envisions an Information
Superhighway, formerly known as the
National Information Infrastructure (NII), to
provide a system of interconnected
networks linking every citizen to multiple
sources of information and means of
communication.
History of the Internet: 1993
• Mosaic, the first navigation browser to
make use of graphics and a point-andclick interface, is developed by Marc
Andreessen.
• Internet traffic proliferates at a 341%
annual growth rate.
History of the Internet: 1994
• Netscape, cofounded by Marc Andreessen
and James Clark, dramatically increases
the popularity of the Web by incorporating
video, sound and animation into their
browser.
• Microsoft is sweating the lose of the
desktop to the Browser
History of the Internet: 1995
• Sun Microsystems introduces Java, a
programming language that makes
animation and other interactive features
commonplace.
• Traditional online services (Compuserve,
AOL and Prodigy) begin to provide
commercial Internet access.
History of the Internet: 1997
• The Internet comprises an estimated
134,000 individual networks, and the
number keeps growing.
• Competing browsers, including Microsoft's
Internet Explorer, appear.
History of the Internet: 1998
• The Web grows from 130 sites in 1993 to
over 2 million sites, and the number keeps
growing.
• Not only are more people using the Web,
but more people, as well as companies
and organizations, are launching their own
sites.
History of the Internet: 2000
• The dot-com bubble burst, numerically,
on March 10, 2000
• One by one, dot-coms ran out of capital
and were acquired or liquidated; the
domain names were picked up by oldeconomy competitors or domain name
investors. Several companies were
accused or convicted of fraud for misusing
shareholders' money.
History of the Internet: 2000
• Failures:
• Boo.com - intention was to sell branded fashion
wear over the Internet; however, after spending
vast sums of its venture capital, it eventually had
to liquidate and was placed into receivership on
May 18, 2000
• eToys - a business, owned and operated as
EToys.com. It collapsed and went bankrupt,
along with many other so-called Dot-com
companies, after the end of the Internet Bubble
on March 10, 2000.
History of the Internet: 2000
• Pets.com - Despite their incredible web traffic and well
known brand name, sales of pet products through the
site were nowhere near profitable - their strategy had
been based around conquering the market on pet
supplies without adequate research on how many pet
owners would genuinely use the service. Money ran out,
the profits never came, and Pets.com was unsuccessful
in raising further capital for their floundering enterprise.
They announced they were closing their doors on the
afternoon of November 6, 2000. Today, the domain name
pets.com redirects to PETsMART's website.
History of the Internet: 2000
• Kozmo.com - Kozmo promoted an incredible business
model; it promised to deliver small goods free of charge.
The company raised about $280 million, including $60
million from Amazon.com. The business model was
heavily criticized by business analysts, who pointed out
that one-hour point-to-point delivery of small objects is
extremely expensive and there was no way Kozmo could
make a profit as long as it refused to charge delivery
fees. Not surprisingly, the company failed soon after the
collapse of the dot-com bubble, laying off its staff of
1,100 employees and shutting down in April 2001.
The History of the Internet: 2000
• Webvan - Was an online "credit and delivery"
grocery business that went bankrupt in 2001. It
is often considered one of the clearest examples
of misapplying Internet technology to an existing
form of business. While Webvan was popular
with consumers, the enormous amount of money
spent on infrastructure far exceeded sales
growth, and the company eventually ran out of
money.
The History of the Internet
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Successful
Amazon.com
eBay
Google
MSN
PayPal (now a subsidiary of eBay)
Priceline.com
Yahoo!
Netflix
Understanding Web server
Administration
• Web server administrators focus on the
Internet
– Need to work with ISPs and Web page
developers
• Typically, a Web server provides
information to anyone who requests it
over the Internet
• Web servers can contain other
applications such as FTP and e-mail
Understanding Web server
Administration
• Depending on the size of the organization,
some tasks may be delegated
– Web page development
– Database design
– Programming
– E-mail administration
– Security
Selecting Programs and
Databases
• Web server administrators need to install
programming languages
• Web developers use a variety of languages
– Active Server Pages (ASP)
• Original language from Microsoft
– ASP.Net
• A newer environment that includes many languages
– Java Server Pages (JSP)
Selecting Programs and
Databases
• Non-Microsoft languages are popular,
even on Microsoft Web servers
– Perl – one of the first and still popular
– PHP – easy to use
– Java Server Pages (JSP)
– Macromedia ColdFusion
Web Databases
• A database management system (DBMS) is
used to store data used with Web pages
– Microsoft Access is appropriate for small sites
– Microsoft SQL Server, Oracle 9i, and MySQL are
sophisticated DBMSs for larger sites
• Standard Query Language (SQL) is the
language used to communicate with the DBMS