Who is surfing Terry's website?

The client-server model is the fundamental architecture of the World Wide Web where server machines respond to requests from client machines by serving content. A client is defined as a requester of services and a server is defined as the provider of services. Note: A single machine can be both a client and a server depending on the software configuration.

A web browser is an example of a client-side application. It requests and receives its data from a remotely located web server application. You click on a link in a web page and - like magic - new content appears.

The Internet Protocol (IP) is the foundation for the World Wide Web. IP is responsible for moving data from one host to another as packets. Each packet is stamped with the addresses of the receiver and the sender and routing decisions are made on a packet-by-packet basis.

Transmission Control Protocol (TCP) creates information packets, verifies that data is delivered across the network accurately and in proper sequence.

On top of TCP/IP are the applications used to deliver data such as:

  • Telnet: The Network Terminal Protocol, which provides remote login over the network
  • FTP: The File Transfer Protocol, which is used for interactive file transfer
  • SMTP: The Simple Mail Transfer Protocol, which delivers electronic mail
  • HTTP: The Hypertext Transfer Protocol, is the set of rules for transferring files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web.

HTTP - the Hypertext Transfer Protocol

HTTP is an application layer protocol, implemented in 1991 by Tim Berners-Lee that sits on top of TCP/IP, the transport protocol. HTTP help solves these problems:

  • Where is the stuff located? HTTP uses URLs (Uniform Resource Locators) to indicate the address of web resources.
  • What kind of stuff is this? HTTP indicates characterizes resources as "text/plain", "image/jpeg", etc.
  • Where should the stuff be sent? HTTP gives the client IP address

Sample URL

 

	...
	<h3>Table of Contents</h3>
	<ol>
		<li><a href="#phrase">Phrases and Paragraphs</a></li>
	</ol>
	...
	...
	<a name=phrase>Phrases and Paragraphs</a>
	...

 

The Domain Name System (DNS)

Every computer on the Internet has an unique address, which is its IP address. The Internet Corporation for Assigned Names and Numbers (ICANN) is a non-profit corporation responsible for the IP address space allocation and domain name system management. The DNS refers to web sites using easy-to-remember domain names (such as "tabrooks.ischool.washington.edu") rather than the numeric IP address (such as 128.208.100.159).

Something to read: Exploding Universe of Web Addresses

Top-Level domains (TLDs)

  • TLDs with two letters (such as .de, .mx, and .jp) have been established for over 240 countries and external territories and are referred to as "country-code" TLDs or "ccTLDs". They are delegated to designated managers, who operate the ccTLDs according to local policies that are adapted to best meet the economic, cultural, linguistic, and legal circumstances of the country or territory involved. Root-Zone Whois Information
  • Most TLDs with three or more characters are referred to as "generic" TLDs, or "gTLDs".
  • ICANN-Accredited Registrars

Names are important and valuable ...

A REAL, PERSONAL example

Yes, there is more than one "Terry Brooks" in this world.
"Terry Brooks"
Author of Sword of Shannara, etc.
Lives in West Seattle, etc. 		"Terry Brooks"
Teacher of this course, etc.
Lives in Shoreline, etc.


Use Statistics of My Website

wwwstat processes a set of HTTP log files and outputs a log summary suitable for publishing on a website.

Whois searching

whois helps you locate server administrators. whois obtains the requested information from the Internet white pages. The white pages is a database of information about the person or corporation registered for a server administration

Anonymous Web Surfing

Anonymizer® Privacy Button Makes Internet Privacy Easier Than Ever

The Anonymizer® Privacy Button works by automatically and transparently routing the user through Anonymizer.com's proxy servers. The encryption-enhanced, protected servers then rewrite Web pages to remove privacy and security threats before serving them to users. Anonymizer hides unique identifiers (such as IP addresses) from Web sites and outside parties, and prevents outside parties from putting malicious files or code on the user's computer. The service also neutralizes cookies, Java, JavaScript, ActiveX, Web Bugs and other potential threats.

Spackers

Call them spackers -- they're the new breed of computer crackers who earn a living in cahoots with spammers.

The latest innovations developed by such mercenary hackers on behalf of the junk e-mail profession are techniques that enable spammers -- or scam artists for that matter -- to create websites that are essentially untraceable.

One group in Poland is currently advertising "invisible bulletproof hosting" in online forums for spammers. For $1,500 per month, the group says it can protect a site from network sleuthing tools used by spam opponents, such as traceroute and whois.

According to Tubul, his group controls 450,000 "Trojaned" systems, most of them home computers running Windows with high-speed connections. The hacked systems contain special software developed by the Polish group that routes traffic between Internet users and customers' websites through thousands of the hijacked computers. The numerous intermediary systems confound tools such as traceroute, effectively laundering the true location of the website. To utilize the service, customers simply configure their sites to use any of several domain-name system servers controlled by the Polish group, Tubul said.

Cloaking Device Made for Spammers    Brian McWilliams. Wired News, October 9, 2003