As early as 195 1, Lincoln Lab of MIT began to design SAGE semi-automatic ground air defense system for the US Air Force. The system was built in 1963, and is considered as the pioneer of computer and communication technology.
The earliest computer communication technology was applied to civil systems. American Airlines and IBM began to jointly study the aircraft booking system SABRE-I in the early 1950s and put it into use in the early 1960s.
1968, the information service system of American General Electric Company was put into operation, which is the largest commercial data processing network in the world. Its geographical scope extends from the United States to Europe, Australia and Japan in Asia, and it has the ability of interactive processing and batch processing. Due to the large geographical scope, the use of time difference can make full use of resources.
Standardized computer network
After 1970s, the local area network developed rapidly. XEROX, DEC and INTEL in the United States have launched Ethernet products based on CSMA/ CD-ROM media access technology. Other big companies have also launched their own products. However, various network products are very different in technology and structure, and there is no unified standard, which brings great inconvenience to users.
1974, IBM announced the system network architecture SNA developed by the network standard according to the layered method. With the appearance of network architecture, various network products produced by a company can be easily interconnected into a network, while products produced by different companies are difficult to connect with each other because of different network architectures.
1984, the international organization for standardization officially promulgated various standard frameworks for computer networking: open interconnection reference model. In the mid-1980s, organizations such as the International Organization for Standardization (ISO) formulated a series of protocol standards with reference to the open interconnection reference model, forming a huge basic protocol set of the open interconnection reference model.
The open interconnection reference model standard ensures the interconnection between computers and network products produced by various manufacturers, and promotes the application and development of network technology. This is called the third generation computer network.
A very important achievement of ARPAnet research is TCP/IP protocol (Transmission Control Protocol/Internet Protocol), which enables all computers connected to the Internet to exchange information with each other. The network established by NSFNET, 1986 is a milestone of the Internet.