The World Wide Web and the Internet MIS XLM.B Jack G. Zheng June 20 th 2005.

The World Wide Web and the Internet

MIS XLM.B

Jack G. ZhengJune 20th 2005

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Overview

The Internet technologies World Wide Web Searching on the Web Connecting to the Internet

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Introduction

The Interneta world-wide network of networks and

computers based on IP (Internet Protocol)

World Wide Web, or WebAn Internet application based on HTTP

protocol

The Internet

Image source: www.wagoneers.com

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First Questions about the Internet

What is the Internet?

Who manages/controls/coordinates the Internet?

How did it come into being?

What can we do on the Internet?

How does it work? Internet backbone Servers Protocols

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The Internet Backbone

How are computers connected world wide?

The Internet Backbone Major sets of connections Network access point (NAP): a point on the Internet

where several connections converge Who operates the Internet backbone?

Network service provider (NSP): Also called backbone operator Usually provide services to ISPs MCI, AT&T, … (see more here)

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Internet Service Provider

ISP is a company that provides individuals, organizations, and businesses access to the Internet

Biggest ISP1

AOL: 23.4M users MSN: 8.7M (2003) United Online (including NetZero and Juno): 6.8M Comcast: 6.0M EarthLink: 5.2M

GSU? GSU wireless access http://wireless.gsu.edu

1 Data from: http://www.isp-planet.com/research/rankings/usa_h.html (2004)

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Internet Servers and Applications

Internet server computer provides information and services on the Internet Web server Mail server FTP (file transfer protocol) server IRC (Internet Relay Chat) server

Router Connects different networks (routing)

Client computer

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Internet Communication Protocols

Communication protocol is a set of rules and format to transfer information

TCP/IP (transmission control protocol/Internet protocol) The featured protocol of the Internet

Application protocols HTTP (hypertext transfer protocol) FTP (file transfer protocol)

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Internet: Putting It Altogether

Adapted from figure B.8 on page 114

Internet backbone

World Wide Web

Total Sites Across All Domains September 1995 - June 2005

Source: http://news.netcraft.com

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Understanding WWW

Some history Tim Berners-Lee, the creator of the Web (1989) Read more

http://www.w3.org/People/Berners-Lee/ http://www.slac.stanford.edu/history/earlyweb/

Three most important things for Web HTML (hypertext markup language) HTTP (hypertext transfer protocol) URL or URI (uniform resource locator)

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Web Common Terms

Link (hyperlink)

Web site vs. web site address Website is a specific location on the web, consisting of a group of

web pages or web applications Website address is a name that identifies a specific website

Web page vs. URL Webpage is a specific file (usually in HTML) in a website URL (Uniform Resource Locator) is an address for a specific web

page or file on the web

!Domain (name) identifies a specific place (computer) on the Internet

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Domain Name

[Domain Name System (DNS)] A system that provides the mapping between IP and domain name Internet Corporation For Assigned Names and Numbers (ICANN)

Top-level domains: 2 letter country code: us, uk, jp, ca, au, cn, … Created in 1980

.com – commercial or for-profit business .net – Internet administrative organization .org – professional or non-profit organization .edu – educational institution .gov – U.S. government agency .int – international treaties organization .mil – U.S. military organization

Created in 2000 coop, info, biz, museum, name, pro, aero

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Understanding URL

http://www2.gsu.edu/~wwwaux/panthercard/index.htm

The complete link is a URL “http” is the protocol “www2.gsu.edu” is the domain “www2.gsu.edu/~wwwaux/” is the web site

(of GSU Auxiliary and Support Services) “index.htm” is the actual file (web page).

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Web Server

Web server Web server hosts websites, providing files and applications

(services)

Market Share for Top Servers Across All Domains. Source: netcraft.com

Web applications software applications

delivered through web technologies (HTTP, HTML, web server, browser, ...)

Examples Searching Shopping News Forum Survey BLog …

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Web Client (Browser)

Web browser software (web client) Provides a web interface for users It understands HTML, scripts and works with other

plug-ins

Web browser products: WorldWideWeb Internet Explorer (Microsoft) Mozilla (formerly Netscape Navigator) Firefox

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Searching on the Web

Two major ways to seek information on the web Searching: using a true search engine Navigating: using structures, such as directories, site

maps, indexes

Search engine A web application that helps you find web pages and

websites with the information and/or services you want Directory search engine

Yahoo! Directory Google Directory (open directory http://dmoz.org/)

True search engine

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True Search Engine

True search engine uses software agent (web crawler) technologies to search the Web and put them into databases; then users search by key words or other criteria

Top 4 providers1

Google (112m searches per day)

AOL (93) Yahoo (42) MSN (32)

Source: businessweek June 11, 2004 1 SIMS study “how much information 2003”

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Connecting To The Internet

Connection type: Dial-up, DSL, Cable?How much do you pay?How fast is the connection?What devices do I need?

Broadband connectionaccounts for more than 50% in 2004,

according to Clickz.com broadband statistics

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Home Networking

[Home networking and Internet sharing] Modem (Wireless) router Network card

Image adapted from D-Link

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Summary

Web is one of the many applications on the Internet

The Internet is built on the Internet backbone, Internet Servers and communication protocols

Understand web common terms Domain URL Web site (address) Web page Search engines

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Web Resources

Histories http://livinginternet.com http://www.netvalley.com/intvalconcl.html

About search engine http://searchenginewatch.com/

How does DNS work http://www.howstuffworks.com/dns.htm

Internet access information http://www.dslreports.com