Brief History of the Internet
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Brief History of the Internet Introduction
This lesson is designed for you to gather information about the history of the internet. When you finish this lesson, you should be able to:
Describe the history of the internet. Describe the history of the world wide web. Describe how browsers evolved. List why standards are important. List the standards organization for the world wide web. Explain what an IP number is. Explain what domains are. Explain how URLs function.
The history of the internet will help you understand how events led up to the development of the world-wide web and browsers. As with most devices used throughout the world, standards for the world wide web are constantly being developed and revised. As a potential web developer, you need to understand this issue.
Related to the internet and the web is internet addressing, domains, and URLs. Knowing how these function will enable you to better conceptual and develop web sites.
To round out your explorations, make sure you complete the Internet Basics Summary . Additional Resources
Webmonkey - Internet Basics [[http://www.hotwired.com/webmonkey/guides/]]
Webmonkey - About the Web [[http://www.hotwired.com/webmonkey/guides/web/index.html]]
Webmonkey - Glossary of Terms [[http://www.hotwired.com/webmonkey/guides/glossary/index.html]]
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History of the Internet
It is important to keep in mind that the internet and the World Wide Web are not the same thing, despite the media's interchangeable use of the terms. The internet is a series of innovations that enables communication and transmission of data between computers at different locations, a network infrastructure of computers around the world that have agreed to share information with each other. The internet has existed for over a decade, providing services such as email and file exchanges to computer scientists and researchers around the world. Technically, the World Wide Web is just another service like email, telnet, FTP, and others that sit atop the infrastructure of the internet.
In the late 50's, President Eisenhower initiated the U.S. Defense Advanced Research Projects Agency (DARPA), a technological think-tank of the American defense effort, in response to the threat of the developing technological superiority by the Russians. Among the projects which were initiated by DARPA was a research program to investigate techniques and technologies for interlinking packet networks of various kinds.
The objective was to develop communication protocols which would allow networked computers to communicate transparently across multiple networks by sending information by breaking a message up into 'packages', sending them separately to their destination and reassembling them at the other end. This was thought to not only be more efficient for the sending of information, but also a more secure method for sending because the system would not be reliant on a single routing and, if files were broken-up before transfer, it would be more difficult to eavesdrop.
By late 1969, the first network was developed consisting of four host machines (UCLA, Stanford Research Institute, UCSB, and the University of Utah) and was known as ARPANET. With continuing developments in the software, by December 1971 ARPANET linked 23 host computers to each other.
In 1974, ARPA scientists, working closely with experts in Stanford, developed a common language that would allow different networks to communicate with each other. The transmission control protocol/internet protocol (TCP/IP) architecture was first proposed by Bob Kahn and further developed by Kahn and Vint Cerf (see: How the internet Came to Be [[http://www.bell- labs.com/user/zhwang/vcerf.html]]) at Stanford. A protocol is a definition of the form of the data that is moved between devices. To decode (understand) the communication, a receiving device must know the protocol with which it was transmitted. TCP/IP is a collection of protocols, it is the protocol that internet devices use to communicate.
By agreeing on a set of common protocols, computers on the internet can exchange information no matter who manufactured the computer and no matter what operating system is in use. Any computer adhering to the TCP/IP protocols can talk to any other computer, regardless of vendor or operating system. So, a Sun workstation running the Solaris operating system can communicate with an IBM mainframe running VM/CMS, and they can both share information even with personal computers, as long as all the machines agree to use the TCP/IP protocols to manage the exchange.
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The development of TCP/IP marked a crucial stage in networking development. It was adopted by the Defense Department in 1980 and universally adopted by 1983. The "internet", a connected set of networks using the TCP/IP standard, was born. In 1984, the number of hosts topped 1000 for the first time.
In 1986, the National Science Foundation funded NSFNet as a backbone for the internet. The effect of the creation of NSFNet was dramatic. It encouraged a surge in internet use. By 1986 the number of hosts had reached 5000 and a year later the figure had climbed to hosts 28,000. It was originally limited to research, education, and government uses, commercial uses were prohibited unless they directly served the goals of research and education. This policy continued until the early 90's, when independent commercial networks began to grow.
Delphi was the first national commercial online service to offer internet access to its subscribers. It opened up an email connection in July 1992 and full internet service in November 1992. In May 1995, the National Science Foundation ended its sponsorship of the internet backbone; commercial, government and university backbones proliferated. By 1989 the number of hosts surpassed 100,000 for the first time and climbed to 300,000 a year later.
The early internet was used by computer experts, engineers, and scientists. It was a complex system to use and there were no standards developed for usage. As the commands for e-mail, FTP, and telnet were standardized, it became easier for non-technical people to learn to use the internet. The usage increased accordingly. In 1991, the first friendly interface to the internet was developed at the University of Minnesota and named Gopher. Gopher was a simple menu system to access files and information and became wide spread.
In 1994 there were 3.2 million hosts and 3,000 web-sites. Twelve months later the number of hosts doubled and the number of web-sites climbed to 25,000. By the end of the next year the number of host computers had doubled again, and the number of web-sites had increased by more than ten-fold. In 1997, the number of host computers integrated into the Web had reached 19.5 million hosts, and the number of web-sites had shot up to 1.2 million. By the last count, in 1998, the number of hosts stood at 36.8 million and the number of web-sites had reached 4.2 million. C. Michael Armstrong, CEO of AT&T, in a recent interview, noted that internet traffic doubles every 100 days.
On October 24, 1995, the Federal Networking Council [[http://www.fnc.gov/internet_res.html]] unanimously passed a resolution defining the term internet. This definition was developed in consultation with members of the internet and intellectual property rights communities.
RESOLUTION: The Federal Networking Council (FNC) agrees that the following language reflects our definition of the term "internet". "Internet" refers to the global information system that --
(i) is logically linked together by a globally unique address space based on the internet Protocol (IP) or its subsequent extensions/follow-ons;
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(ii) is able to support communications using the Transmission Control Protocol/internet Protocol (TCP/IP) suite or its subsequent extensions/follow-ons, and/or other IP-compatible protocols; and
(iii) provides, uses or makes accessible, either publicly or privately, high level services layered on the communications and related infrastructure described herein.
Additional references:
A Brief History of the Internet [[http://www.isoc.org/internet-history/brief.html]] gives an overview of the origins and history written by individuals who were involved in the development and evolution of the internet.
History of internet and WWW: The Roads and Crossroads of internet History: [[http://www.internetvalley.com/intval.html]]
Internet Timeline: [[http://www.pbs.org/internet/timeline/ ]]
Listing of additional links: [[http://www.netvalley.com/netvalley/history-refer.html]]
According to the Computer Industry Almanac [[http://www.c-i-a.com/]] the U.S. has an overwhelming lead in internet users with over 119 million as of year-end 1999, which is nearly 43% of the total 259 million worldwide internet users. 25% of the population of the US is using the internet, 30% of the males and 21% of the females. North America will remain the leading region for internet users until at least 2005. It will grow from about 93 million internet users at year-end 1998 to nearly 231 million by year-end 2005. Western Europe/Scandinavia is growing faster than North America and will be a close second by 2005 with over 213 million internet users. The Asia-Pacific region is growing even faster and will have nearly 190 million internet users in 2005.
Sources for internet usage statistics:
Nielsen//NetRatings [[http://www.nielsen-netratings.com/ ]]
CyberAtlas: internet Statistics and Market Research for Web Marketers [[http://cyberatlas.internet.com/]]
NetWatch Demographic Stats [[http://cyberatlas.internet.com/big_picture/demographics/article/0,1323,5901_225371,00.html]]
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WWW Development
There were two developments that are responsible for the Web as we know it today, the development of the protocols for the internet and the development of hypertext. The World Wide Web (WWW) is a set of internet protocols and software that present information in a hypertext format.
While the adoption of the TCP/IP protocol resulted in the rapid expansion of the internet, another individual, Tim Berners-Lee [[http://www.w3.org/People/Berners-Lee/]], and others at the European Laboratory for Particle Physics, more popularly known as CERN, proposed a new protocol for information distribution. Scientists at CERN were struggling to find a way to share a huge variety of documents, ranging from experimental data to computer documentation to up-to-the-minute news of scientific breakthroughs, with the large community of physicists who could benefit from such access.
Tim Berners-Lee first conceived of the protocols that make it possible for Web documents to be accessible to desktop computers around the world. In a note to his colleagues at CERN, Tim Berners-Lee shared his perception of a need:
"The current incompatibilities of the platforms and tools make it impossible to access existing information through a common interface, leading to waste of time, frustration and obsolete answers to simple data lookup.
There is a potential large benefit from the integration of a variety of systems in a way which allows a user to follow links pointing from one piece of information to another one."
- WorldWideWeb: Proposal for a HyperText Project; Tim Berners-Lee, Robert Cailliau; 1990. [[http://www.w3.org/Proposal.html]]
This protocol, which became the World Wide Web in 1991, was based on hypertext - a system of embedding links in text to link to other text. The WWW was created under the pretense that many people would be able to work collaboratively by putting information on a web of hypertext documents.
The protocol developed, Hypertext Transfer protocol (HTTP), simplified the writing of addresses and automatically searched the internet for the address indicated and automatically called up the document for viewing. For decades, access to computers and computer networks was through text-only terminals or terminal emulator programs. The first Web browser, a line-mode browser that could only run on text-only, VT 100 terminals, was developed by Berners-Lee and released to the public in 1991. Berners-Lee coined the name World Wide Web as a name for the program. WWW could be put on servers and the browser, would allow one to access the information stored on the server. By the end of 1992 there were only 50 web-sites in the World and a year later the number was still no more than 150.
Additional resource:
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The History, Current State, and Future of the World Wide Web [[http://php.engr.iupui.edu/~snisonge/main.html]]
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Browser Development
In 1993 Mark Andreesen of NCSA (National Center for SuperComputing Applications, Illinois) launched Mosaic X. This browser was released to the public on X, PC /Windows, and Macintosh platforms and was an immediate hit. It was easy to install, easy to use and enormously improved the graphic capabilities of the web. Mosaic made it possible for users with direct or dialup internet connections to navigate through the Web viewing multimedia documents, complete with different fonts, styled text, and inline graphics. By 1994 tens of thousands of versions had been installed on computers throughout the World. The potential of HTML to create graphically attractive web-sites and the ease with which these sites could be accessed through the new generations of web-browsers opened the Web to whole new groups. These developments were accelerated by the appearance of ever-more powerful and affordable personal computers and by the increase in capacity of the communications infrastructure. The Web now exploded.
In April 1994, Marc Andreessen, who conceived and spearheaded the development of Mosaic, left NCSA to co-found Mosaic Communications in Mountain View, California. (The company changed its name to Netscape Communications in November of that year.) In October 1994, the first version of Netscape Navigator was made available on the internet and was the most successful graphical type of browser and server until Microsoft declared war and developed its MicroSoft Internet Explorer. At the end of 1995, Microsoft realized the rising importance of the internet and committed itself to establishing dominance in the Web browser market.
Compared to the available versions of Netscape, the first two releases of Internet Explorer were uneventful. However, the release of Internet Explorer 3.0 in August 1996 and its subsequent incorporation into future versions of the Windows operating system signified Microsoft's first serious entry into the World Wide Web browser market. In January of 1996, only 6.4% of the browsers used were Internet Explorer. By January 2000, 48.1% of the browsers being used were Internet Explorer and 39.8% were Netscape.
Additional resources:
BrowserWatch: Up to date information on browsers [[http://browserwatch.internet.com/]]
BrowserWatch: Stats Station [[http://browserwatch.internet.com/stats.html]]
Information on browser types: [[http://www2.whidbey.net/jmwallin/resources/ua.html]]
Reference chart of browser features: [[http://hotwired.lycos.com/webmonkey/reference/browser_chart/]]
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Development of Standards
In the software industry, there is usually a push to develop standards, or protocols, that similar pieces of software all use. The World Wide Web Consortium (W3C) [[http://www.w3.org/]] was founded in September 1994 and is responsible for setting the standards for HTML, and for deciding what is “official” HTML and what is not. Browser companies frequently release HTML tags that are not official HTML tags as defined by W3C. These browser-specific HTML tags are dubbed HTML extensions. Tim Berners-Lee, the current director of W3C, describes the W3C's mission: "to realize the full potential of the web, by bringing its members and others together in a neutral forum." The Consortium is where companies and organizations to whom the future of the Web is important come to discuss and to agree on new common computer protocols.
Tim Berners-Lee has put together a list of frequently asked questions about the development of the WWW and his role in the process, as well as some of his perspectives on the Web at http://www.w3.org/People/Berners-Lee/FAQ.html
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Internet Addressing
For a client computer to execute an application on a server that it is connected to using TCP/IP, the client needs to know
the server's IP address, and the application's IP port.
IP Numbers
The internet is a packet-switching network. Information that is sent is broken into several individual packets, each of which contains addressing information for its ultimate destination. The packets take whatever routes are available to get to their final address, where they are reassembled into the correct order. Packets are able to find their ultimate destination because every single computer on the internet has a unique identifying address, called an IP number. Machines on the internet called routers send the data packets along until they reach the machine with the specific IP number contained in the packet.
IP numbers contain four parts, separated by decimals, containing a number between 0 and 255, for example, 146.186.234.7. The rightmost number specifies the actual machine, while those to the left identify the network and subnetwork.
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Domains & Domain Names
One early, and essential development, was the introduction in 1984 of Domain Name Servers (DNS). The Domain Name System was devised so that any machine with an IP number could also have a more meaningful text-based name. The Domain Name System lets us use addresses like www.psu.edu instead of 146.186.234.7. Like an IP number, an internet address in the Domain Name System has several parts, each separated by a decimal. When you use a domain name address to attach to some resource such as a Web server, a special Domain Name Service (DNS) looks up the name and replaces it with an IP number.
The last part of a domain name address is called the top-level domain. There are six standardized domain names currently in use, corresponding to types of organizations.
.com Commercial entity .edu Educational institution .gov Government agency or department .mil Military organization .net Network resource .org Other type of organization, usually a not-for-profit
The committee in charge of these naming standards, recently added seven more top-level names to the list. These may also be used by anyone registering a new name:
.firm for businesses .store for online stores .web for Web-related organizations .arts for cultural and entertainment organizations .rec for organizations emphasizing recreational activities .info for organizations that provide information .nom for individuals who want to be identified as such
In addition, internet sites outside the United States are identified by a special two-letter, top-level domain name; for example, .ca is the code for Canada; .jp is the code for Japan, and .nl is the code for the Netherlands. There is a two-letter designation for the United States, .us, but it is seldom used since the six "organization type" names are more descriptive.
Every name is registered with a special internet organization to ensure that it is unique. The internet Network Information Center (InterNIC) maintains DNS and administers IP addresses and domain names. You can find out more about registering domain names (and obtaining IP addresses) on InterNIC's Web site, http://www.internic.net.
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URLs
As developed by Berners-Lee, the software calls up the information by searching for a link's URL (Uniform Resource Locator). It then uses HTTP (HyperText Transfer Protocol) to get the document which is coded in HTML (HyperText Markup Language). Uniform Resource Locators provide the protocol and addressing information that a browser uses to connect to the target document. The first part of a URL specifies the type of data or the protocol necessary to retrieve the data; the second part is the domain name that specifies the server where the information is located; and the optional third part specifies the path name or directory where that data is stored. There are three basic components of a URL:
Type specifier Host or machine identifier Path identifier and file extension
In the following sample URL http://www.phillies.com/schedule/april.html http is the type specifies, www.phillies.com is the host identifier, and schedule/april.html is the path identifier listing the exact file. specifier://hostname/pathname/filename.extension
Type Specifiers
The item that makes it possible for the Web browser to know when to expect different protocols is the type specifier in the URL, which is always the first item. The type specifier lets the browser know, before it even starts to look for the item in cyberspace, what kind of object it is going to be working with: a Web page, a gopher site, or an FTP file archive.
HTTP stands for Hypertext Transport Protocol, which is the primary protocol of the World Wide Web. HTTP is the mechanism that allows hypertext Web pages and their associated links and graphics to be displayed correctly on the client.
Host Name Identifiers
In all URLs that require accessing a remote server, the second part of the URL is always the name of the internet host.
Port Numbers in URLs
Certain ports on the server are designated by number to handle specific kinds of packets. Most World Wide Web servers communicate on IP port 80. This means that it is easy for client applications - such as web browsers - to jump from web server to web server. All the browser needs to know is the server's IP address. When you use a URL to make a request of a remote
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However, some servers may request that packets of a certain type go to a different port number from the well-known port number. In this case, the host name in the URL is followed by a colon and the number of the port that should be used instead of the well-known port number. For example http://www.mysite.com:59/
Pathnames
The pathname is the third item in a URL, the pathname tells the Web browser exactly where to find the file you're looking for in the host machine's directory structure. Pathnames are a way of representing the name of a file in a hierarchical file system. In order to find a specific file, you need to know not only its name but also the path to the directory in which it resides.
File extensions
The last item in a pathname may be a file extension, appended to the name of the file after a decimal. For example http://www.mysite.com/index.htm
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Brief History of the Internet Summary
This lesson was designed for you to gather information about the history of the internet. When you are finished with this lesson, you should be able to do the following:
Describe the history of the internet. Describe the history of the world wide web. Describe how browsers evolved. List why standards are important. List the standards organization for the world wide web. Explain what an IP number is. Explain what domains are. Explain how URLs function.
A short summary of these topics are listed below. If you cannot do these things, you should review the lesson at least once. If you are still having difficulty, you should consider other sources of information that compliment this lesson, such as textbooks, tutors, and instructors.
History of the Internet
President Eisenhowerinitiated the U.S. Defense Advanced Research Projects Agency (DARPA). Among the projects which were initiated by DARPA was a research program to investigate techniques and technologies for interlinking packet networks of various kinds.
By late 1969, the first network was developed consisting of four host machines (UCLA, Stanford Research Institute, UCSB, and the University of Utah) and was known as ARPANET.
In 1974, ARPA scientists developed a common language that would allow different networks to communicate with each other - transmission control protocol/internet protocol (TCP/IP).
In 1984, the number of hosts using TCP/IP to communicate topped 1000 for the first time.
In 1986, the National Science Foundation funded NSFNet as a backbone for the internet. By 1986 the number of hosts had reached 5000 and a year later the figure had climbed to hosts 28,000.
In 1991, the first friendly interface to the internet was developed at the University of Minnesota and named Gopher. Gopher was a simple menu system to access files and information and became wide spread.
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Delphi, the first national commercial online service to offer internet access to its subscribers, opened up an email connection in July 1992 and full internet service in November 1992.
In 1994 there were 3.2 million hosts and 3,000 web-sites. Twelve months later the number of hosts doubled and the number of web-sites climbed to 25,000.
Recently, C. Michael Armstrong, CEO of AT&T, noted that internet traffic now doubles every day.
WWW Development
Tim Berners-Lee and others at the European Laboratory for Particle Physics, more popularly known as CERN, proposed a new protocol for information distribution for scientists.
This protocol - the World Wide Web - was based on hypertext - a system of embedding links in text to link to other text.
The first Web browser, a line-mode browser that could only run on text-only, VT 100 terminals, was developed by Berners-Lee and released to the public in 1991.
Browser Development
In 1993 Mark Andreesen of NCSA (National Center for SuperComputing Applications, Illinois) launched Mosaic X. Mosaic was graphics capable.
By 1994 tens of thousands of versions of Mosaic had been installed on computers throughout the World.
In April 1994, Marc Andreessen left NCSA to co-found Mosaic Communications in Mountain View, California. The company changed its name to Netscape Communications in November of that year.
In October 1994, the first version of Netscape Navigator was made available on the internet
At the end of 1995, Microsoft realized the rising importance of the internet and committed itself to establishing dominance in the Web browser market.
The release of Internet Explorer 3.0 in August 1996 and its subsequent incorporation into future versions of the Windows operating system signified Microsoft's first serious entry into the World Wide Web browser market.
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By January 2000, 48.1% of the browsers being used were Internet Explorer and 39.8% were Netscape.
Development of Standards
The World Wide Web Consortium (http://www.w3.org/) was founded in September 1994 and is responsible for setting the standards for HTML, and for deciding what is “official” HTML and what is not.
Internet Addressing
IP numbers contain four parts, separated by decimals, containing a number between 0 and 255, for example, 146.186.234.7. The rightmost number specifies the actual machine, while those to the left identify the network and subnetwork.
Domains & Domain Names
The Domain Name System was devised so that any machine with an IP number could also have a more meaningful text-based name. The Domain Name System lets us use addresses like www.psu.edu instead of 146.186.234.7.
An internet address in the Domain Name System has several parts, each separated by a decimal.
URLs
There are three basic components of a URL:
Type specifier Host or machine identifier Path identifier and file extension
In this example: http://www.phillies.com/schedule/april.html http is the type specifies, www.phillies.com is the host identifier, and schedule/april.html is the path identifier listing the exact file.
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