ARPAnet (Earliest Internet) Formed 1969
The Advanced Research Projects Agency Network (ARPAnet) set the infrastructure that would become the Internet. ARPAnet began as a network of connected university computers. The ARPAnet was funded by the Defense Advanced Research Projects Agency. The original basis was to develop a network for military command and control after a nuclear attack. The computer network was based on telephone lines and required a new technology known as packet switching to move data on telephone lines between computers. After its startup in 1969, ARPAnet evolved into several innovations in the early 1970s such as email, a file transfer protocol, which allows data to be sent in bulk, and a remote connecting service for network computers. This network grew to connect universities across the nation with defense funding. When the Defense Department pulled out of the project in 1990, it had laid the groundwork for today’s worldwide Internet. Universities continued the old network as NSFnet as it expanded to individuals with the advent of the Personal Computer.
The roots of the ARPAnet go back to the funding of the Defense Advanced Research Projects Agency (DARPA) formed in 1957 as a response to the launching of Sputnik. DARPA was created as a very special research group for the Department of Defense. The name was changed in 1958 to Advanced Research Projects Agency (ARPA). ARPA had an annual $12 million budget and much flexibility on spending it. Its first project was to look at a communications network that could operate after a nuclear attack on the United States. This bombproof network would allow distant military centers to communicate. ARPA adapted the early work of the 1960s of Paul Baran of the Rand Institute. This early network research had been financed by the Air Force. Baran’s work was on a packet switching system that would allow information to be routed on any available electronic lines such as telephone lines. The packet switching concept of Paul Baran was a revolutionary idea of breaking data or messages in packets to flow along available lines and then be reassembled at the designation machine. This differed from a traditional phone call that used circuit switching to form a dedicated circuit for the duration of the communication session. Packet switching allows data to flow on a fractured network unable to develop a dedicated or “direct” hook up. Packet switching is a special computer protocol allowing computers to exchange information (network control protocol).
Baran’s packet switching network offered another possibility of connecting universities involved in research for the Defense Department. At the time computers even in the same room could not talk to each other let alone at different universities. Packet switching along telephone lines would be a necessity to move large blocks of research data. These connections would allow huge amounts of data to be transported between universities. Beyond packet switching, some hardware to handle the messages had to be developed. Since ARPA was a small core group, it contracted out the work to BNN Technologies. To connect distance computers, each location required a gateway computer known as an Interface Message Processor (IMPs or routers as they are known today). The first IMP was built by Honeywell and could service four local computers. The first network connected computers at UCLA and the Stanford Research Institute in September of 1969. UCLA and Stanford both had SDS computers. Initially after typing “login,” the system shutdown, taking another month to work out the bugs for a message, which was ultimately sent at 10:30 p.m. October 29, 1969.
By the end of 1969, an IBM 360 at the University of California, Santa Barbara, and a DEC at the University of Utah were added to the network. MIT was added to the network in March of 1970. In 1971, the first e-mail was sent; and by 1973 with over 40 sites, e-mail made up 75 percent of the traffic, which augured the future of the Internet. To send a message on the ARPAnet required a computer to break the message into packets using an Internet Protocol (IP). The packets also received a digital identification because individual packets might take different paths. Individual packets are routed based on traffic. When the individual packet envelopes reach the destination computer, Transmission Control Protocol (TCP) reassembled the message in correct order. The network was slow running at 50 to 200 kbit/second. The year 1971 also brought the use of a Terminal Interface Processor (TIP) capable of adding over 60 slave terminals to the host computer. By the mid-1970s, huge databases were being passed between universities using File Transfer Protocol (FTP). The ARPAnet had achieved its goal and was supporting both military and civilian research applications. In 1983, the ARPAnet was split into National Science Foundation network (NSFnet) and the classified military network (MILnet).
ARPAnet continued as a communication system between certain research pockets at various universities until most of the IMP routers became obsolete in 1989.
The NSFnet used Local Area Networks (LANs) to link whole universities internally and externally. The NSFnet started to look for more funding as the ARPAnet shutdown in 1990. In 1991, Senator Albert Gore crafted and the Congress passed the High Performance Computing and Communication Act. The bill created and funded a super information highway for research, which evolved into the Internet of today. Today’s Internet is made up of the same infrastructure of routers and protocols. The Internet, regardless of its government origins, remained firmly rooted in the private industry.
