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Web Servers
November 15, 2005
Slides modified from
Internet & World Wide Web: How to Program. 2004 (3rd)
edition. By Deitel, Deitel, and Goldberg. Published by
Prentice Hall. ISBN 0-13-145091-3
1
Chapter 21 – Web Servers
(IIS and Apache)
Outline
21.1
21.2
21.3
21.4
21.5
21.6
21.7
21.8
21.9
Introduction
HTTP Request Types
System Architecture
Client-Side Scripting versus Server-Side Scripting
Accessing Web Servers
Microsoft Internet Information Services (IIS)
21.6.1 Microsoft Internet Information Services (IIS) 5.0
21.6.2 Microsoft Internet Information Services (IIS) 6.0
Apache Web Server
Requesting Documents
21.8.1 XHTML
21.8.2 ASP.NET
21.8.3 Perl
21.8.4 PHP
21.8.5 Python
Web Resources
2
Objectives
• In this lesson, you will learn:
– To understand a Web server’s functionality.
– To introduce Apache Web server.
– To learn how to request documents from a
Web server.
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21.1 Introduction
• Web server
– Responds to client requests by providing
resources
• URI (Uniform Resource Identifier)
• Web server and client communicate with
platform-independent Hypertext Transfer
Protocol (HTTP)
4
21.1 Introduction
IIS 5.0
Microsoft
Corporation
5.0
2/17/00
Windows 2000,
Windows XP
IIS 6.0
Microsoft
Corporation
6.0
3/28/03
Windows Server 2003
Apache Web server
Company
Apache Software
Foundation
Version
2.0.47
Released
7/10/03
Platforms
Windows NT/2000/XP,
Mac OS X, Linux and
other UNIX-based
platforms,
experimentally supports
Windows 95/98
Brief
The most popular The newest release of Currently the most
description
Web server for
IIS from Microsoft.
popular Web server.
Windows 2000.
Price
Included with
Included with
Freeware.
Windows 2000
Windows Server 2003
and Windows
XP.
Fig. 21.1 Web servers discussed in this chapter.
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Web server architecture
6
How the WWW Works
(Fitzgerald and Dennis, 2005 Figure 2.8)
7
Domain
Name
Server
System
(Fitzgerald and Dennis, 2005 Figure 5.8)
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Example of an HTTP Request
from a Web browser
Command
URL
HTTP version
GET http://www.kelley.indiana.edu/ardennis/home.htm HTTP/1.1 ]- Request
Line
Date: Mon 06 Aug 2001 17:35:46 GMT
User-Agent: Mozilla/6.0 ]- Web browser (this is Netscape)
Request Header
Referer: http://www.indiana.edu/~aisdept/faculty.htm
URL that contained the link to the requested URL
(Fitzgerald and Dennis, 2005 Figure 2-9)
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HTTP response from a Web server
HTTP version
Status code
Reason
HTTP/1.1
200
OK ]- Response Status
Date: Mon 06 Aug 2001 17:35:46 GMT ]- Date
Server: NCSA/1.3 ]- Web server
Location: http:// www.kelley.indiana.edu/adennis/home.htm ]- URL
Content-type: text/html ]- Type of file
<html>
<head>
<title>Allen R. Dennis</title>
</head>
<body>
<H2> Allen R. Dennis </H2>
<P>Welcome to the home page of Allen R. Dennis</P>
Response
Header
Response
Body
</body>
</html>
(Fitzgerald and Dennis, 2005 Figure 2-10)
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21.2 HTTP Request Types
• GET (default) and POST do basically the same thing:
Send data from the client to the server. However, they
have some differences:
• GET
– Appends form data directly to the end of the URL—visible to
users (not suitable for sending passwords)
– Limited to 2,048 characters for the entire URL
– Result page can be bookmarked and cached
• POST
– Sends form data in the HTTP request—invisible to users
– Virtually no limit (but check your specific configuration)
– Results are not cacheable or bookmarkable
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21.3 System Architecture
• Multi-tier application (n-tier application)
– Information tier (data or bottom tier)
• Maintains data for the application
• Stores data in a relational database management system
(RDBMS)
– Middle tier
• Implements business logic and presentation logic
• Control interactions between application clients and
application data
– Client tier (top tier)
• Application’s user interface
• Users interact directly with the application through the client
tier
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N-tier Client-Server Architecture
(Fitzgerald and Dennis, 2005 Figure 2.5)
13
21.4 Client-Side Scripting
versus Server-Side Scripting
• Client-side scripts
– Validate user input
• Reduce requests needed to be passed to server
• Access browser
• Enhance Web pages with DHTML, ActiveX controls, and
applets
• Server-side scripts
–
–
–
–
Executed on server
Generate custom response for clients
Wide range of programmatic capabilities
Access to server-side software that extends server
functionality
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Installing a web server
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Hosting a website:
Self hosting
• Install a web server on a computer
• Local access
– Using domain <localhost>
– or IP address 127.0.0.1
– Necessary for server-side programming development
• Global access
– Register a human-readable domain name
– Obtain IP address
• Static: Costs more
• Dynamic: Needs dynamic DNS system, e.g.
http://www.dyndns.com/
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Hosting a website:
Hosting service
• Register a domain name
– Assign name servers
– Host takes care of IP addressing
• Develop website locally
• Upload website via FTP for global access
– E.g. Filezilla
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Web server architecture
• LAMP: Most popular—fully open source
–
–
–
–
Linux for operating system
Apache for web server
MySQL for database
PHP for server-side scripting
• Others:
– WAMP: Uses Windows for operating system, with
Apache, MySQL, and PHP
– WISA: Full Microsoft package
•
•
•
•
Windows
Internet Information Server (IIS)
SQL Server (enterprise) or Access (small-scale)
ASP or ASP.NET
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21.7 Apache Web Server
•
•
•
•
•
Currently the most popular Web server
Stability
Efficiency
Portability
Open-source
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All-in-one Apache/MySQL/PHP
packages
• EasyPHP (recommended)
– Includes PHPMyAdmin for administering
MySQL database
– Installation and configuration
• AbriaSoft Merlin Desktop Edition
– Includes PHPMyAdmin
• WAMP Server
• PHP Triad
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Installing EasyPHP
• Download EasyPHP, and follow the installation
instructions
• In addition, move the <mysql> and <phpmyadmin>
folders into the <www> folder in the EasyPHP installation
folder
• For Windows 95, make the following adjustments before
starting EasyPHP:
– Download the Windows NT patch, rename it to EasyPHP.exe,
and replace the existing EasyPHP.exe
– Open DOS prompt, go to the EasyPHP installation folder, and
run <easyphp /install>
• Run EasyPHP in Windows, and it will start Apache and
MySQL (PHP and PHPMyAdmin do not need to “start”)
– Note that Windows 95 might show that Apache is not working,
though actually it is working
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Requesting XHTML or PHP
documents
• Request PHP documents from Apache
• Save PHP documents in the www folder for
EasyPHP (htdocs is the default Apache folder
name)
• Launch web browser
– With EasyPHP, right-click on the status bar icon and
click “Local Web”
• Enter PHP document’s location in Address field,
starting with http://localhost/ or http://127.0.0.1/
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21.8.1 XHTML and PHP
Fig. 21.15
Fig. 21.23
Requesting test.html from IIS 6 or Apache.
Requesting test.php from Apache.
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21.9 Web Resources
• www.microsoft.com/msdownload/ntoptionpack/askwiz.a
sp
• www.w3.org/Protocols
• www.apache.org
• httpd.apache.org
• httpd.apache.org/docs-2.0
• www.apacheweek.com
• linuxtoday.com/stories/18780.html
• www.iisanswers.com
• www.iisadministrator.com
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References
• Fitzgerald, Jerry and Alan Dennis, 2005.
Business Data Communications and
Networking. 8th edition. Wiley: New York.
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