chapter 8 web server hardware and software
Download
Skip this Video
Download Presentation
Chapter 8: Web Server Hardware and Software

Loading in 2 Seconds...

play fullscreen
1 / 37

Chapter 8: - PowerPoint PPT Presentation


  • 212 Views
  • Uploaded on

Chapter 8: Web Server Hardware and Software. Objectives. In this chapter, you will learn about: Web server basics Software for Web servers E-mail management and spam control issues Internet and Web site utility programs Web server hardware. Web Server Basics.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Chapter 8:' - flora


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
objectives
Objectives

In this chapter, you will learn about:

  • Web server basics
  • Software for Web servers
  • E-mail management and spam control issues
  • Internet and Web site utility programs
  • Web server hardware
web server basics
Web Server Basics
  • The main job of a Web server is to respond to requests from Web client computers
  • There are 3 components of a Web server:
    • Hardware
    • Operating system software
    • Web server software
types of web sites
Types of Web Sites
  • Development sites: Used to evaluate different Web designs
  • Intranets: Corporate networks that house internal memos, corporate policy handbooks, and a variety of other corporate documents
  • Extranets: Intranets that allow authorized parties outside the company to access information stored in the system
  • Transaction-processing sites: Commerce sites that must be available 24 hours a day, seven days a week
  • Content-delivery sites: Deliver content such as news, histories, summaries, and other digital information
web clients and web servers
Web Clients and Web Servers
  • Client/server architectures
    • Client computers request services
    • A server processes the clients’ requests
  • Web software is platform neutral, meaning that it lets different types of servers communicate with a variety of clients
dynamic content
Dynamic Content
  • Dynamic content is nonstatic information constructed in response to a Web client’s request
    • Dynamic page: Web page whose content is shaped by a program in response to user requests
    • Static page: An unchanging page retrieved from disk
dynamic content7
Dynamic Content
  • Server-side scripting (or includes)
    • Programs running on a Web server create Web pages before sending them back to the requesting Web clients
  • Dynamic page-generation technologies: Server side scripts are combined with html tags to create dynamic content
    • Active Server Pages (ASP)
    • JavaServer Pages (JSP)
    • PHP: Hypertext Preprocessor (PHP)
various meanings of server
Various Meanings of “Server”
  • Server
    • Computer used to provide files or make programs available to other computers
      • Server software: Used by a server to make files and programs available to other computers
      • Database server: Server on which database management software runs
two tier client server architecture
Two-Tier Client/Server Architecture
  • Two-tier client/server architecture has one client and one server
two tier client server architecture10
Two-Tier Client/Server Architecture
  • Request message: Message that a Web client sends to request a file or files from a Web server
    • Typical request message contains:
      • Request line
        • Contains a command, the name of the target resource, and the protocol name and version number
      • Request headers
        • Can contain information about types of files that the client will accept in response to a request
      • Entity body
        • Used to pass bulk information to the server
three tier and n tier client server architectures
Three-Tier and N-Tier Client/Server Architectures
  • Three-tier architecture
    • Extends two-tier architecture to allow additional processing (e.g., collection of data from a database) before reponses to requests are made
  • N-tier architectures
    • Higher-order architectures
    • Third tier includes software applications that interactively supply and update information to and from the web server
web server software
Web Server Software
  • The most popular Web server programs are:
    • Apache HTTP Server
    • Microsoft Internet Information Server (IIS)
    • Sun Java System Web Server (JSWS)
  • Netcraft
    • A networking consulting company in Bath, England
    • Accumulates popularity rankings
apache http server
Apache HTTP Server
  • Apache is the results of an ongoing group software development effort, first developed by Rob McCool at the University of Illinois in 1994 at theNCSA
  • Apache has dominated the Web since 1996 because it is free (open source) and performs efficiently
microsoft internet information server
Microsoft Internet Information Server
  • Comes bundled with current versions of Microsoft Windows Server operating systems
  • Used on many corporate intranets
  • Supports the use of:
    • ASP
    • ActiveX Data Objects
    • SQL database queries
electronic mail e mail
Electronic Mail (E-Mail)
  • We all know the benefits of email
  • Email drawbacks include:
    • Time spent by business people responding to e-mail
    • Computer viruses
      • Programs that attach to other programs
      • Can cause damage when the host program is activated
    • Spam
slide17
Spam
  • Spam is unsolicited or commercial e-mail
  • During one 24-hour period in 2005 researchers estimated that 106 billion spam e-mail messages were sent
solutions to the spam problem
Solutions to the Spam Problem
  • Reduce the likelihood that a spammer can automatically generate e-mail addresses
  • Control exposure of an e-mail address
  • Use multiple e-mail addresses
  • Content filtering strategy
    • Requires software that identifies content elements that indicate if a message is (or is not) spam
solutions to the spam problem20
Solutions to the Spam Problem
  • Content-filtering techniques
    • Black list spam filter
      • Looks for known spammer From addresses in incoming messages
    • White list spam filter
      • Examines From addresses and compares them to a list of known good sender addresses
    • Challenge-response technique
      • Compares all incoming messages to a white list
web site and internet utility programs
Web Site and Internet Utility Programs
  • Finger
    • Runs on UNIX operating systems
    • Allows users to obtain information about other network users
    • Command yields a list of users who are logged on to a network
  • Ping (Packet Internet Groper)
    • Tests connectivity between two computers connected to the Internet
tracert and other route tracing programs
Tracert and Other Route-Tracing Programs
  • Tracert (TRACE RouTe)
    • Sends data packets to every computer on the path between one computer and another
    • Clocks packets’ roundtrip times
    • Calculates and displays the number of hops between computers
    • Calculates the time it takes to traverse an entire one-way path between machines
telnet and ftp utilities
Telnet and FTP Utilities
  • Telnet
    • Program that allows users to log on to a computer connected to the Internet
  • Telnet protocol
    • Set of rules used by Telnet programs
  • File Transfer Protocol (FTP)
    • Defines formats used to transfer files between TCP/IP-connected computers
indexing and searching utility programs
Indexing and Searching Utility Programs
  • Search engines or search tools
    • Search either a specific site or the entire Web for requested documents
  • Indexing program
    • Can provide full-text indexing that generates an index for all documents stored on a server
    • Can often index documents stored in many different file formats
data analysis software
Data Analysis Software
  • Web servers can capture:
    • Data about who is visiting a Web site
    • How long the visitor’s Web browser viewed the site
    • Date and time of each visit
    • Which pages a visitor viewed
  • Data captured by Web servers are stored in a log file
link checking utilities
Link-Checking Utilities
  • Link checker examines each Web page and reports on URLs that:
    • Are broken
    • Seem broken
    • Are incorrect in some way
  • Orphan file
    • File on a Web site not linked to any page
  • Dead link
    • When clicked, it displays an error message rather than a Web page
remote server administration
Remote Server Administration
  • Web site administrator can control a Web site from any Internet-connected computer
  • NetMechanic
    • Offers a variety of link-checking, HTML troubleshooting, site-monitoring, and other programs
web server hardware
Web Server Hardware
  • Web server computers
    • More memory, larger hard disk drives, and faster processors than typical PCs
  • Blade servers
    • Placing small server computers on a single computer board, then installing boards into a rack-mounted frame
  • Virtual server (virtual host)
    • Maintains more than one server on one machine
web server performance evaluation
Web Server Performance Evaluation
  • Benchmarking
    • Testing used to compare the performance of hardware and software
  • Throughput
    • Number of HTTP requests that a hardware and software combination can process in a unit of time
  • Response time
    • Time required by a server to process one request
web server hardware architectures
Web Server Hardware Architectures
  • Server farms
    • Large collections of servers
  • Centralized architecture
    • Uses a few very large and fast computers
  • Distributed/decentralized architecture
    • Uses a large number of less powerful computers
    • Divides the workload among them
load balancing systems
Load-Balancing Systems
  • Load-balancing switch
    • Piece of network hardware that monitors the workloads of servers attached to it
    • Assigns incoming Web traffic to a server that has the most available capacity at that instant in time
summary
Summary
  • The Web uses a client/server architecture
  • For simple HTTP requests a two-tier architecture works well
  • Operating systems commonly used on Web server computers include:
    • Microsoft server operating systems
    • UNIX-based operating systems
summary36
Summary
  • Utility programs running on Web server computers include:
    • Finger, Ping, Tracert, e-mail server software, Telnet, and FTP
  • Unsolicited commercial e-mail (spam) has grown dramatically in recent years
    • Content filters are becoming available to deal with the problem
summary37
Summary
  • Web server hardware
    • Server computer must have enough memory and disk space
  • Factors that affect Web server performance include:
    • Operating system
    • Connection speed
    • User capacity
ad