The Early Years

In the fifties and early sixties, prior to Internet, most communication networks only allowed communications between the stations on the network. One prevalent computer networking method was based on the central mainframe method which allowed its terminals to be connected via long leased lines. The mainframe method was used in the 1950s by Project RAND which supported researchers that collaborated with other researchers across the country regarding automated theorem proving and artificial intelligence.

One of the pioneers of the internet was J.C.R Licklider who called for a global network in his January 1960 paper “Man-Computer Symbiosis.” Licklider’s idea he called for was,
"a network of such [computers], connected to one another by wide-band communication lines" which provided "the functions of present-day libraries together with anticipated advances in information storage and retrieval and [other] symbiotic functions.”

Licklider was later appointed in October of 1962 as the head of the United States Department of Defense's DARPA information processing office, and formed an informal group within DARPA to further computer research.

Three terminals

As part of the information processing office's role, three network terminals had been installed: one for System Development Corporation in Santa Monica, one for Project Genie at the University of California, Berkeley and one for the Multics project SHOPPING at the Massachusetts Institute of Technology (MIT). Licklider's need for inter-networking would be made evident by the problems this caused.

Robert W. Taylor, a co-writer with Licklider of the article entitled, "The Computer as a Communications Device", made the following statement in an interview with the New York Times;
"For each of these three terminals, I had three different sets of user commands. So if I was talking online with someone at S.D.C. and I wanted to talk to someone I knew at Berkeley or M.I.T. about this, I had to get up from the S.D.C. terminal, go over and log into the other terminal and get in touch with them.
I said, oh, my goodness gracious me, it's obvious what to do (But I don't want to do it): If you have these three terminals, there ought to be one terminal that goes anywhere you want to go where you have interactive computing. That idea is the ARPAnet."

Note: The problems that Licklider and Taylor faced could have been solved with today’s instant messaging services that allow internet users to chat on-line with many people from all over the world at once!

Switched Packets

This inter-networking problem laid the issue of finding a way to connect separate physical networks to form one logical network. During the 1960s, Donald Davies of NPL, Paul Baran of the RAND Corporation, and Leonard Kleinrock of MIT developed and implemented “packet switching” (the notion that the Internet was developed to survive a nuclear attack has its roots in the early theories developed by RAND.) Baran's research had approached packet switching from studies of decentralization to avoid combat damage compromising the entire network.

ARPANET

Robert Taylor was later promoted to the head of the information processing office at ARPA and wanted to carry out Licklider’s idea of an interconnected networking system. He joined Larry Roberts from MIT to help build this network. The first ARPANET link was established between the University of California in Los Angeles and the Stanford Research Institute in November of 1969. By December of that same year, the University of Utah and the University of California in Santa Barbara, California was also added making it a 4-node network. ARPANET grew every year and by 1981, ARPANET had 213 hosts.

ARPANET became the foundation of what would eventually become the Internet. Making ARPANET international was tough at first for various political reasons though the Norwegian Seismic Array (NORSAR) and Sweden joined by linking to the Tanum Earth Station and University College London with satellites.

Packet switching network standards were developed by the International Telecommunication Union (ITU) in the form of X.25. X.25 formed the basis for the SERCnet network between British academic and research sites, which later became JANET.

Note: X.25 was different from ARPANET because it was also commonly available for business use and would be used for the first dial-in public access networks, such as Compuserve and Tymnet.

Later in 1978, the British Post Office, Western Union International and Tymnet joined forces to create the first international packet switched network, referred to as the International Packet Switched Service (IPSS). Over the next three years, the network grew from Europe and the US to cover Canada, Hong Kong and Australia.

Note: This was groundbreaking as the internet was finally providing a worldwide networking infrastructure. The following image is a web showing how everything is connected.

Compuserve

In 1979, CompuServe became the first service to offer electronic mail or “e-mail” capabilities and technical support to personal computer (PC) users. In 1980, the company broke new ground again as the first service to offer real-time chat with its CB Simulator.

Note: Real-time chat is also called “instant messaging.”

Later, other companies joined the internet bandwagon such as America Online (AOL), the Prodigy dial-in network, and many bulletin board system (BBS) networks such as FidoNet.

With so many different network methods, something needed to bring them together. Robert E. Kahn of DARPA and ARPANET recruited Vint Cerf of Stanford University to work with him on the problem. By 1973, they had soon worked out an ultimate reformulation, where the differences between network protocols were hidden by using a common internetwork protocol. So, instead of the network being responsible for reliability, as in the ARPANET, the individual hosts became responsible.

Since hosts were now responsible, the role of the network reduced to the bare minimum and it became possible to join almost any networks together, no matter what their characteristics were. This solved Kahn's initial problem. DARPA funded the development of the software and they eventually conducted the first demonstration of a gateway between the Packet Radio network in the SF Bay area and the ARPANET.

TCP/IP

By November 1977, a three network demonstration was conducted including the ARPANET, the Packet Radio Network and the Atlantic Packet Satellite network. DARPA encouraged the development of TCP/IP implementations for many operating systems and then enforced all of the hosts on all of its packet networks to TCP/IP. In 1983, TCP/IP protocols became the only approved protocol on the ARPANET.

ARPANET to NSFNet

ARPANET’s primary business was funding revolutionary research and development, not running a communications utility. Because of this, they turned the network over to the Defense Communications Agency, part of the Department of Defense. In 1983, the U.S. military portion of the ARPANET was broken off as a separate network, the MILNET.

Since the network was funded by the government, it was restricted to noncommercial use solely for research purposes; anything else was prohibited. Because of the restrictions, the network was also restricted to military sites and universities. During the 1980’s however, the network expanded to more educational institutions across the globe. Also, companies such as the Digital Equipment Corporation and Hewlett-Packard (which were participating in research projects or providing services to those who were) joined.

The National Science Foundation (NSF), another branch of the U.S. government, became heavily involved in internet research as well and started CSNET, a successor to ARPANET, which became the first Wide Area Network specifically designed to use TCP/IP. This developed into the NSFNet backbone which was established in 1986. It intended to connect and provide access to a number of supercomputing centers established by the NSF.

The transition

The term "Internet" was adopted in the first RFC published on the TCP. It was around the time when ARPANET was interlinked with NSFNet that the term “internet” came into more general use. An “internet” was basically a synonym for any network using TCP/IP. The internet gradually came to mean “a global and large network that was using TCP/IP”, which at the time meant NSFNet and ARPANET.

Note: The terms "internet" and "internetwork" had been used interchangeably, and "internet protocol" had been used to refer to other networking systems such as Xerox Network Services.

As interest in the rapidly expanding network grew and new applications for it were constantly arriving, the Internet's technologies began to cover the entire world and gained worldwide interest. TCP/IP's network-agnostic approach made it easy to use any existing network infrastructure to carry Internet traffic. In 1984, University College London, which was previously connected by transatlantic satellite links, switched to TCP/IP over IPSS.

Gateways were created for sites that were unable to link directly to the internet. These gateways allowed transfer of e-mail, which at that time was the most important and sought after application. Sites which only had irregular connections used UUCP or FidoNet and relied on the gateways between these networks and the Internet for access. Some gateway services went beyond simple e-mail peering and began offering other services such as allowing access to FTP (file transfer) sites via UUCP or e-mail.

Opening to the World

As word of the internet was growing, many people wanted to use it for commercial use. Though commercial use of the internet was forbidden, the exact definition of commercial use was unclear and subjective and that prompted the official barring of UUCPNet use of ARPANET and NSFNet connections.

During the late 1980s, the first Internet service provider (ISP) companies were formed. They provided service to the regional research networks and provide alternate network access, UUCP-based email and Usenet News to the public. The first dial-up ISP, world.std.com, opened in 1989.

Because of explosion of new users (see graph above), controversy rose amongst university users who were outraged at the idea of non-educational use of their networks that was originallymeant for them. Eventually, commercial Internet service providers offered low enough that juniorcolleges and other schools could afford to participate in the new arenas of education and research.

In 1990, ARPANET was overtaken and replaced by the newer networking technologies and the project came to a close. In 1994, ANSNET (Advanced Networks and Services), formerly NSFNet, began allowing non-profit corporations access and lost its title as the backbone of the Internet. Both government institutions and competing commercial providers began to create their own networks and interconnections. Regional network access points (NAPs) became the primary interconnections between the many networks and finally, the commercial restrictions ended. [1]

The New Internet

With the commercial restrictions finally over, the internet became what it is today, a vast computer network linking smaller computer networks which includes commercial, educational, governmental, and other networks, all of which use the same set of communications protocols. [2]