THE HISTORY OF THE INTERNET (STUDY OBJECTIVE 2)
Much of the technology foundation upon which the Internet is based was developed by university and military researchers nearly 50 years ago. To understand the current status of the Internet, it is useful to briefly review the historical development of the Internet and the underlying technology. In 1965, a researcher at MIT connected a computer in Massachusetts to a computer in California, using dial-up telephone lines. During this time, the U.S. military needed a method of sharing data and research among universities that were working on defense research projects. In 1969, the large computers at four major universities were connected via leased telephone lines. This network, used by the United States Defense Advanced Research Project Agency, grew into a network called ARPANET. The purpose of the network was to share military research data among UCLA, UC Santa Barbara, Stanford, and the University of Utah. Over the next few months, many other universities, NASA, and the Rand Corporation were connected to this network.
Two of the technologies developed for ARPANET form the basic foundation of the Internet of today. Packet switching and routers are necessary to send data over the network. Packet switching is the method used to send data over a computer network. Computer data are divided into packets (small packages of data). Each packet is sent individually over the network, with each packet possibly transmitted via a different route. When the packets arrive at the destination, they are reassembled into the correct order to recreate the original data. When data are sent packet switched, small parts of the data are transmitted, they are verified for correctness, and then more information is sent toward the destination.
A router is an electronic hardware device that is located at the gateway between two or more networks. The router forwards the packets of data along the best route so that the data reach their destination. The ARPANET used both of these technologies, which have continued to be used in the Internet of today.
The ARPANET was developed during the height of the Cold War and nuclear weapon proliferation. Thus, the network was designed so that if some of the sites were destroyed by a nuclear attack, the other sites could still function and share the military research data. Therefore, routers were designed to route the network traffic via many possible alternative routes.
E-mail, which is simply another form of data that can be transmitted over a network, was adapted to ARPANET in 1972. Ray Tomlinson of BBN Technologies developed the idea of using the @ symbol to separate the user name from the address. BBN Technologies has been involved in much of the development of the Internet. BBN Technologies also developed a communication protocol for ARPANET that is still used today. Since there were several different brands, or types, of computers in the network ARPANET, a common communication protocol was necessary to allow different types of computers to communicate. A protocol is a standard data communication format that allows computers to exchange data. Computers must have a common communication method to be linked together in a network. As an analogy, think about what would happen if a foreign exchange student from Japan met a foreign exchange student from Spain in the hallway of the business building at your college. They would be completely unable to communicate in their native languages. However, if both were accompanied by an English translator, their native languages could be translated into English, communicated between the translators (the network), and then translated into the language of either student. Likewise, a common and standard communication protocol allows computers with different operating systems to communicate on a network. Thus, a UNIX® computer, or Digital Equipment Company's (DEC) OpenVMS can communicate with a Windows or Apple computer.
In the 1970s, BBN Technologies helped develop the TCP/IP protocol that continues in use in the Internet today. TCP/IP is an abbreviation for transmission control protocol/Internet protocol.
Through the 1970s and 1980s, the ARPANET continued to add universities, research organizations, and libraries to its network. However, other than universities, libraries, and research organizations, there were no other users of ARPANET. In 1986, the National Science Foundation (NSF) funded and began to develop a backbone set of servers, gateways, and networks that eventually became what we now call the Internet. The NSF also set rules for the use of the Internet by government, university, and research users. Throughout its history of development, and until the early 1990s, the Internet was not user friendly and was not used by the general public. The Internet is the global computer network, or “information super-highway.” The term “Internet” comes from the concept of inter connected networks. Thus, the Internet evolved from a variety of university- and government-sponsored computer networks built largely for research. That network became the Internet and is now made up of millions upon millions of computers and subnetworks throughout the world. The Internet serves as the backbone for the World Wide Web (WWW).
In 1993, Marc Andreessen developed the first graphical user interface (GUI) browser, which he named Mosaic. Using the ideas and concepts in the Mosaic browser, Andreessen developed the Netscape® Navigator Web browser. Netscape became a phenomenon and fueled the use of the Internet by the general public. A GUI browser made the use of the Internet user friendly so that the Internet could be used by the general public. During this period, more commercial enterprises became involved in adding to the network backbone of servers, routers, and gateways. In 1992, commercial enterprises such as Delphi Corporation and America Online (AOL) began offering Internet access to subscribers. This was the first time that the general public could access the Internet by buying a monthly subscription account with an Internet service provider. In 1994, the first business transaction occurred on the Internet.
In 1995, the NSF relinquished control of the Internet backbone to commercial enterprises, and the NSF funded backbone was separated from the Internet and returned to a research network. Since that time, all Internet traffic has been routed through commercial networks. The latter half of the decade of the 1990s saw the explosive growth of the Internet. Retailers and other corporations began to conduct business via the Internet, and many new Internet-based companies were formed. Companies such as Amazon.com, eBay, Webvan, and Pets.com were started during this time. These are only a few examples of the so-called dot-com firms of the 1990s, some of which did not survive beyond the beginning of the next decade.
As the Internet grew, the backbone was continually updated and improved to build in additional servers, routers, and networks that transmit data much faster. The speed and the amount of network traffic grew very rapidly as the technology allowed improvements. The exponential growth of the Internet throughout its life can be seen in Exhibit 14-2.
As you will note by looking at Exhibit 14-2, there have been a few periods of decline in the number of Web servers, such as during economic downturns in 2002 and 2009. However, the overall trend shows exponential growth since the Internet was commercialized.
Exhibit 14-2 Chart of the Number of Web Servers
