Meeting 13. web server i

1
1
11 to 1
Computer Network Administration
Web Server - Introduction Web Server

2
2
22 to 2
INTRODUCTION TO WEB SERVER
 Web server
 Specialized software that responds to client requests by providing
resources
 When users enter URL into Web browsers, they request specific
documents from Web server
 Maps URL to file on server and returns requested document to
client
 Communicates with client using HTTP
 Protocol for transferring requests and files over the Internet
 Example of Web servers
 Internet Information Services (IIS), Personal Web Server (PWS),
Apache Web Server, Tomcat.

3
3
33 to 3
FIgure 1. Architecture Web Server

4
4
44 to
HISTORY
 A web server is server software, or hardware dedicated to running said
software, that can satisfy World Wide Web client requests. A web
server can, in general, contain one or more websites. A web server
processes incoming network requests over HTTP and several other
related protocols.
 The primary function of a web server is to store, process and deliver
web pages to clients.[1] The communication between client and server
takes place using the Hypertext Transfer Protocol (HTTP). Pages
delivered are most frequently HTML documents, which may include
images, style sheets and scripts in addition to the text content.

5
5
55 to
HISTORY
 In March 1989 Sir Tim Berners-Lee proposed a new project to his
employer CERN, with the goal of easing the exchange of information
between scientists by using a hypertext system. The project resulted
in Berners-Lee writing two programs in 1990:
 Between 1991 and 1994, the simplicity and effectiveness of early
technologies used to surf and exchange data through the World Wide
Web helped to port them to many different operating systems and
spread their use among scientific organizations and universities, and
subsequently to the industry.
 In 1994 Berners-Lee decided to constitute the World Wide Web
Consortium (W3C) to regulate the further development of the many
technologies involved (HTTP, HTML, etc.) through a standardization
process.

6
6
66 to 6
Market shareMARKET SHARE #1
 February 2019
Below are the latest statistics of the market share of all sites of the
top web servers on the Internet by W3Techs Usage of Web Servers
for Websites.
https://w3techs.com/technologies/overview/web_server/all
All other web servers are used by less than 1% of the websites.

7
7
77 to
 July 2018
for Websites.
All other web servers are used by less than 1% of the websites.

8
8
88 to
 February 2016
for Websites.
Apache, IIS and Nginx are the most used web servers on the World
Wide Web.

9
9
99 to 9
USAGE OF WEB SERVER
This diagram shows the percentages of websites using various web servers. See technologies overview
for explanations on the methodologies used in the surveys. Our reports are updated daily. How to read
the diagram: Apache is used by 43.9% of all the websites whose web server we know.

10
10
1010 to 10
The following web servers are used by less than 0.1% of the websites
 Lighttpd
 Caddy
 Oracle Servers
 Gunicorn
 Zope
 IBM Servers
 Jetty
 Hiawatha
 WEBrick
 WildFly
 Resin
 Kangle
 micro_httpd
 Thin
 Zeus
 WSGIserver
 Akka HTTP
 Tornado
 Paste WSGI HTTP Server
 H2O
 Roxen
 Waitress
 OpenBSD httpd
 Cherokee
 Mongrel
 IceWarp
 NetWeaver Application Server
 Abyss
 CherryPy
 AOLserver
 Twisted
 Yaws
 thttpd
 WebToB
 NaviServer
 WebSTAR
 RaidenHTTPD
 Jexus
 SAP J2EE Engine
 CL-HTTP
 Hunchentoot
 AllegroServe
 nxweb
 G-WAN
 Xitami
 Barracuda Server
 BaseHTTPServer
 CouchDB
 Noelios Restlet Engine
 Caudium
 KomHttpServer
 Mathopd
 Monkey
 Orion

11
11
1111 to 11
The following web servers are used by less than 0.1% of the websites
 Orion
 Trifork
 Virtuoso
 Ada Web Server
 Gatling
 mini_httpd
 Swazoo
 Wildcat
 Blazix
 Comanche
 FAPWS
 KeyFocus
 Lwan
 Misultin
 Mongrel2
 Tcl-Webserver
 Tntnet
 WebHare
 WebSiphon
 Xavante

12
12
1212 to 12
WEB SERVER PLATFORM
IIS PWS Apache
Company Microsoft
Corporation
Microsoft
Corporation
Apache Software
Foundation
Version 5.0 4.0 1.3.20
Released 2/17/00 12/4/97 5/21/01
Platforms Windows 2000 Windows 95/98/
Millennium Edition (Me)/NT
UNIX, Windows NT/2000,
experimentally supports Windows
95/98
Brief
description
The most popular Web
server for Windows 2000.
A basic Web server for publishing
personal Web pages.
Currently the most
popular Web server.
Price Included with
Windows 2000.
Freeware. Packaged with Microsoft
IIS in NT 4.0 Option Pack. Also
included in
Windows 98.
Freeware.

13
13
1313 to 13
GENERAL SERVER CHARACTERISTICS
 Web servers have two separate directories
 The document root is the root directory of all servable documents
(well, not really all)
 e.g. Suppose the site name is www.bloomers.com and the
document root is named topdocs, and it is stored in the
/admin/web directory
 So, /admin/web/topdocs is the document directory address
 If a request URL is:
http://www.bloomers.com/bulbs/tulips.html
The server will search for the file with the given path
/admin/web/topdocs/bulbs/tulips.html
 The server can have virtual document trees
 Sometimes a different disk, possibly on a different machine,
is used after the original disk is filled

14
14
1414 to 14
 The server root is the root directory for all of the code that
implements the server
 The server root usually has four files
 One is the code for the server itself
 Three others are subdirectories
 conf - for configuration information
 logs - to store what has happened
 cgi-bin - for executable scripts
 Contemporary servers provide many services:
 Virtual hosts - multiple sites on the same system
 Proxy servers - to serve documents from the document roots of
other sites
 Besides HTTP, support for FTP, Gopher, News, email
 Support for database access
GENERAL SERVER CHARACTERISTICS

15
15
1515 to 15
 Also known as request methods
 Most popular are get and post
 Retrieve and send client form data to Web server
 get request
 Sends form content as part of URL
 Retrieves appropriate resource from Web server
 Limits query to 1024 characters
 post request
 Updates contents of Web server (posting new messages to
forum)
 Has no limit for length of query
 Not part of URL and cannot be seen by user
HTTP REQUEST TYPES

16
16
1616 to 16
 Posts data to server-side form handler
 Browsers cache (save on disk) Web pages
 Allows for quick reloading
 Cache responses to get request
 Do not cache responses to post request
HTTP REQUEST TYPES

17
17
1717 to 17
 Requesting documents
 Must know machine name on which Web server resides
 Through local Web servers or remote Web servers
 Through domain name or Internet Protocol (IP) address
 Local Web server
 Resides on users’ machines
 Requests documents in two ways
 Machine name
 localhost (Host name that references local machine)
ACCESSING WEB SERVER

18
18
1818 to 18
 Remote Web server
 Resides on different machines
 Domain name
 Represents group of hosts on Internet
 Combines with how name (www) and top-level domain to from fully
qualified host name
 Top-level domain (TLD)
 Describes type of organization that owns domain name
 .com or .org
 Fully qualified host name
 Provides user friendly way to identify site on Internet

19
19
1919 to 19
 IP address
 Unique address for locating computers on Internet
 Domain name server (DNS)
 Maintains database of host names and corresponding IP
addresses
 Translates fully qualified host name to IP address
 Known as DNS lookup

20
20
2020 to 20
INTERNET INFORMATION SERVICES
 Internet Information Services (IIS)
 Enterprise-level Web server
 Included with Windows 2000
 Allows computer to serve documents
 Internet Services Manager (FIGURE A)
 Open Control Panel, double click Administrative Tools icon, then
double click Internet Services Manager icon
 Administration program for IIS
 Place documents to be requested in default directory or virtual
directory
 Default: C:InetpubWwwroot
 Virtual: alias for existing directory on local machine

21
21
2121 to 21
Start > Settings > Control panel> program and features > turn windows features on and off

22
22
2222 to 22
FIgure 2. : Internet Services Manager dialog.

23
23
2323 to 23
 Default FTP Site and Default Web Site
 Permit transferring documents between computer and server
 HTTP used frequently to request documents
 Default SMTP Virtual Server
 Allows for creation of mail server
 Create virtual directory in Default Web Site
 Most Web documents reside in Webpub directory
 Right click Webpub, select New, then Virtual Directory
 Initiates Virtual Directory Creation Wizard (Figure B)
 Guides user through virtual directory creation process

24
24
2424 to 24
Figure 3. Virtual Directory Creation Wizard welcome dialog.

25
25
2525 to 25
 Virtual Directory Alias (Fig. C)
 Enter name for virtual directory
 Name should not conflict with an existing virtual directory
 Web Site Content Directory (Fig. D)
 Enter path of directory containing Web documents
 Access Permissions (Fig. E)
 Presents security level choices
 Select access level appropriate for Web document

26
26
2626 to 26
Figure 4. Virtual Directory Alias dialog.

27
27
2727 to 27
Figure 5. Web Site Content Directory dialog.

28
28
2828 to 28
 Access Permissions (Figure E)
 Presents security level choices
 Select access level appropriate for Web document
 Read allows users to read and download files
 Run Scripts allows scripts to run in directory
 Execute allows applications to run in directory
 Write allows Web page to accept user input
 Browse allows users to navigate between documents
 Read and Run Scripts selected by default

29
29
2929 to 29
Figure 6. Access Permissions dialog.

30
30
3030 to 30
PERSONAL WEB SERVER (PWS)
 PWS
 Scaled-down version of IIS
 Intended for personal computers (PC)
 Ideal for educational institutions, small businesses and individuals
 Does not require PC to be used exclusively as Web server
 Personal Web Manager (Fig. F)
 Administration program for PWS
 Place documents to be requested in default directory or virtual
directory
 Default: C:Inetpubwwwroot
 Virtual: alias for existing directory on local machine

31
31
3131 to 31
Figure 7. Personal Web Manager dialog.

32
32
3232 to 32
 Edit Directory (Fig. G)
 Directory field
 Enter directory path that contains Web documents
 Alias field
 Enter name to virtual directory
 Access section
 Select security level for virtual directory
 Read allows users to read and download files
 Execute allows applications to run in directory
 Scripts allows scripts to run in directory
 Read and Scripts selected by default

33
33
3333 to 33
Figure 9. Creating a virtual directory in PWS in Edit Directory.

34
34
3434 to 34
 Apache Web Server
 Maintained by Apache Software Foundation
 Currently most popular Web server
 Stable
 Efficient
 Portable
 Successively select Start Programs Apache httpd Server 
Control Apache Server  Start (Figure H)
APACHE WEB SERVER

35
35
3535 to 35
Figure 10. Starting the Apache Web server.

36
36
3636 to 36
• Client-Server Architectures
• Client tasks:
• Provide a way for users to submit queries
• Run applications that use the results of queries
• Display results of queries
• Server tasks:
• Implement a data manipulation language, which can directly
access and update the database
• A two-tier system has clients that are connected directly to the server.
SISTEM ARCHITECTURE

37
37
3737 to 37
SYSTEM ARCHITECTURE – 2 tier
Figure 11. 2 Tier Sistem Architecture

38
38
3838 to 38
• Problems with a two-tier system:
• Because the relative power of clients has grown considerably,
we could shift processing to the client, but then maintaining
data integrity is difficult
• Web server part of multi-tier application
• Divide functionality into separate tiers
• Logical groupings of functionality
• Can reside on same computer or on different computers
• Following diagrams illustrates 3-tier application

39
39
3939 to 39
Client Tier
MiddleTier
InformationTier
SYSTEM ARCHITECTURE- 3 tier
Figure 12. 3 Tier Sistem Architecture

40
40
4040 to 40
• Client tier
– Referred to as top tier
– Application’s user interface
– Users interact with application through user interface
– Interacts with middle tier to make requests and to
retrieve data from information tier
– Displays data to user

41
41
4141 to 41
• Information tier
– Referred to as data tier or bottom tier
– Maintains data for application
– Stores data in relational database management system
• Middle tier
– Implements business logic and presentation logic
– Controls interactions between application clients and
application data
– Acts as intermediary between data in information tier and
application clients

42
42
4242 to 42
• Middle tier (cont)
– Controller logic
• Processes client requests from top tier
• Retrieves data from database
– Presentation logic
• Processes data from information tier
• Presents content to client
– Business logic
• Enforces business rules
– Dictates how clients can access application data and how
applications process data
• Ensures data validity before updating database

43
43
4343 to 43
• Zolfagharifard, Ellie (24 November 2018). "'Father of the web' Sir Tim Berners-Lee on
his plan to fight fake news". The Telegraph. ISSN 0307-1235. Retrieved 1 February
2019.
• Vaughan-Nichols, Steven J. "Apache and IIS' Web server rival NGINX is growing
fast". ZDNet. Retrieved 1 February 2019.
• Hadi, Nahari (2011). Web commerce security: design and development. Krutz,
Ronald L. Indianapolis: Wiley Pub. ISBN 9781118098899. OCLC 757394142.
• http://www.juntak.com/bus107/MATERIALS/Powerpoint_Presentations/08.ppt
• https://en.wikipedia.org/wiki/Web_server
• https://razorjr.files.wordpress.com/2014/01/lecture8_web_server_browser.ppt
REFERENCE

Meeting 13. web server i

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Meeting 13. web server i

Similar to Meeting 13. web server i (20)

More from Syaiful Ahdan

More from Syaiful Ahdan (20)

Recently uploaded

Recently uploaded (20)

Meeting 13. web server i