Web E-Commerce
Ch. 8 Lecture Notes

Objective #1: Understand the basics of web servers.

  • A web server combines hardware, an operating system, and web server software.
  • The goals that a company has for its website, the purpose of the site, and the budget affect what combination of elements are used for the company's web server.
  • Type of websites include development sites, intranets, extranets, transaction-processing sites, & content-delivery sites.
  • Since the platform of the Web is neutral, there are a lot of choices for a web server software and hardware.
  • In the first years of the Internet, many websites only contained static pages. But now, dynamic pages make up a lot more of the Web. A dynamic page often integrates a database and a server-side scripting language with static HTML. Server-side scripting and server-side includes were popular in the first years of the Internet. But they are not used as much anymore. Instead, dynamic page-generation technologies such as PHP, ASP, JSP, or ColdFusion.
  • The term "server" can be used to refer to the actual computer (i.e. hardware) that ties together client computers using hubs, switches, and routers. This server serves files (i.e file server) or programs (application server) to client computers. But a server needs an operating system and one or more programs to fulfill this role so often the term "server" is used to refer to the OS or server software that is installed on the this computer. A server that is tied to the Internet is called a web server. Other kinds of servers include file servers, application servers, print servers, database servers, and others.

Objective #2: Explain the software that is used with web servers.

  • Two-tier client/server architecture consists of a client computer requesting packets of data directly from a web server. However, in some cases a three-tier architecture is used to allow additional processing. Usually a database server or a specific application server is the third computer involved. The client communicates to the web server which in turn communicates with the database or application server. In some cases, though, an n-tier system involves 4 or more computers including content servers, media servers, ecommerce servers, and others.
  • A web server needs to have an operating system and web server software. Popular operating systems for web servers are Solaris UNIX, FreeBSD Unix, Linux, Windows 2003, Windows 2000, etc. UNIX is the most popular since its secure and it was the oldest. Linux is growing in popularity since it is open-source and can run on various types of computers including PC's. UNIX typically requires more powerful Sun, HP, or IBM computers.
  • Popular web server software includes Apache, Microsoft IIS, and Sun Java System Web Server (JSWS). Apache is the most popular with about 70% of the market, since it is the oldest and it's open-source. It is also very secure and flexible. Many intranet web servers use MS IIS and Sun server software. The netcraft.com survey at http://news.netcraft.com/archives/web_server_survey.html is frequently updated to show the market share for popular server platforms.

Objective #3: Explain how email management is currently accomplished and explain spam control issues.

  • Email has overwhelmed many businesses leading to a loss in worker productivity. Viruses and the potential damage to corporate networks is also an issue.
  • Spam is probably the worst problem associated with email.
  • To deal with spam a company can:
    • give unpredictable email addresses to its employees
    • keep from listing employee email addresses in web sites where bots can harvest them
    • teach its employees to use multiple, disposable email addresses
    • client-level or server-level email filtering
    • use black lists and white lists
    • use a challenge-response system
    • use advanced content filtering searching the bodies of emails for keywords
    • use Bayesian filtering
  • The federal gov't tried to get a handle on the spam problem when it passed the CAN-SPAM law in Jan. 2004
  • Industry may revamp the way email is delivered but technical proposals are still in development.

Objective #4: List and explain various utility programs used in conjunction with web servers and maintaining web sites.

  • dnsstuff.com can be used to perform PING's and traceroutes
  • FTP
  • Telnet & SSH clients
  • indexing software to allow searches of company websites
  • site statistics and programs that analyze server log files (e.g. WebTrends)
  • link checkers that look for orphans and dead links
  • remote server administration (e.g. NetMechanic and Web Site Garage)
  • virtual hosting provider control panel software

Objective #5: Describe the range of web server hardware.

  • Any computer could be used as a web server. But you would at least want a beefed up personal computer for a small business that is hosting its own website. Many companies use Sun computers and spend up to $400,000 for web servers.
  • Virtual servers allow for one server (i.e. one computer) to host thousands of websites each with its own domain name. Virtual hosting can be found for as little as $10/year but $10/month is a reasonable amount to spend for a basic non-ecommerce web site and $40/month is reasonable for an ecommerce-enabled site.
  • Blade servers are popular to squeeze more servers into small spaces and server farms are large collections of servers under one roof.