The USSR launches Sputnik, the first artificial earth satellite. In the late 1960’s the U. S. military was desperately afraid of a nuclear attack from the Soviet Union. The United States formed the Advanced Research Projects Agency (ARPA) within the Department of Defense to establish a bombproof network to connect military bases. ARPANET’s physical network was established in 1969 to enable universities and research organizations to exchange information freely. The first two nodes that formed the ARPANET were UCLA and he Stanford Research Institute, shortly after the University of Utah was added to ARPANET.
The Network Control Protocol (NCP) was initially used as the ARPANET protocol, beginning in 1970. By 1971, a total of 23 hosts at 15 locations were connected to the ARPANET. The following year, the first international connections occurred, linking the University College of London (UK) and the Royal Radar Establishment (Norway) to the ARPANET. The way ARPANET was set up is so that if one of the network links became disrupted by nemy attack, the traffic on it could automatically be rerouted to other links.
Fortunately, the Net rarely has come under enemy attack. In the 1970s, ARPA also sponsored further research into the applications of packet switching technologies. This included extending packet switching to ships at sea and ground mobile units and the use of radio for packet switching. Ethernet was created during the course of research into the use of radio for packet switching, and it was found that coaxial cable could support the movement of data at extremely fast rates of speed.
The development of Ethernet was crucial to the growth of local area computer networks. The success of ARPANET made it difficult to manage, particularly with the large and growing number of university sites on it. So it was broken into two parts. The two parts consisted of MILNET, which had the military sites, and the new, smaller ARPANET, which had the nonmilitary sites. On January 1,1983, every machine connected to ARPANET had to use TCP/IP. TCP/IP became the core Internet protocol and replaced NCP (old ARPANET language) completely.
Thanks to TCP/IP MILNET and ARPANET remained connected through a technical scheme called IP (Internet Protocol); which enables traffic to be routed from one network to another as necessary. All the networks connected to the Internet speak IP, so they all can exchange messages. Although there were only two networks at that time, IP was designed to allow for tens of thousands of networks. An unusual fact about the IP design is that every computer on an IP network is just as capable as any other, so any machine can communicate with any other machine.
In 1985 the National Science Foundation began announcing plans for its new T1 lines, which would be finished by 1988. Soon after the completion of the T1 backbone, traffic increased so quickly that plans immediately began on upgrading the network again. The same year the concept of the T3, a 45 Mbps was introduced to the public. While the T3 lines were being constructed, the Department of Defense disbanded the ARPANET and the T1 and later T3 backbone replaced ARPANET. The original 50Kbs lines of ARPANET were taken out of service.
In 1990 ARPANET was replaced by the National Science Foundation Network (NSFNET), the same company that founded the t1 and t3, to connect its supercomputers to regional networks. In my opinion I think the government did an excellent job in developing the Internet. Essentially, the ARPANET can be viewed as the embryo from which the Internet grew. The government fostered and encouraged the growth of private Internet corporations. Today the Internet spans across all 7 continents and connects the whole world with some clicks of a mouse and typing at the keyboard.