How was the earliest computer network invented?

The earliest Internet was established by the Advanced Research Projects Agency (ARPA) of the US Department of Defense. Many concepts and methods of modern computer network, such as packet switching technology, all come from ARPAnet. ARPAnet not only studied the packet switching technology of leased line interconnection, but also studied the packet switching technology of wireless and satellite networks, which led to the emergence of TCP/IP.

In 1977- 1979, ARPAnet introduced the current TCP/IP architecture and protocol. Around 1980, all the computers on ARPAnet started the conversion of TCP/IP protocol, and the initial Internet with ARPAnet as the backbone network was established. 1983, all ARPAnet computers completed the conversion to TCP/IP, and realized TCP/IP on UNIX (BSD 4.1). The biggest contribution of ARPAnet in technology is the development and application of TCP/IP protocol. Two famous science education networks have been established successively: China Science Network and BITNET. 1984, NSF of the National Science Foundation planned to establish 13 National Supercomputing Center and National Education Science and Technology Network. Then it replaced the backbone position of ARPANET. 1988 the internet began to open to the outside world. 199 1 June, 2006, among computers connected to the Internet, commercial users surpassed academic users for the first time, which was a milestone in the development history of the Internet, and the growth rate of the Internet was out of control.