The Internet first originated from the ARPAnet established by ARPA, the predecessor of the U.S. Department of Defense Advanced Research Projects Agency (DARPA), which was put into use in 1969. Since the 1960s, ARPA began to provide funding to the computer science departments of universities within the United States and a number of private limited companies to promote research on computer networks based on packet-switching technology. 1968, ARPA for the ARPAnet network project, the project is based on the leading idea: the network must be able to withstand failures to maintain the normal operation of the network in the event of war, when a part of the network due to damage to the network, the network will be able to maintain the normal operation of the network, the network will be able to withstand failures to maintain the normal operation of the network. In the event of war, when one part of the network is incapacitated by an attack, the rest of the network should be able to maintain normal communications. Initially, ARPAnet was used primarily for military research purposes, and it had five major features:
(1) support for resource ****enjoyment;
(2) use of distributed control technology;
(3) use of packet-switching technology;
(4) use of communication control processors;
(5) use of layered network communication protocols.
In 1972, ARPAnet met the public for the first time at the first International Conference on Computer Backend Communications and verified the feasibility of packet-switching technology, thus making ARPAnet the symbol of the birth of modern computer networks.
Another major technical contribution of ARPAnet was the development and use of the TCP/IP protocol cluster. 1980, ARPA invested in adding TCP/IP to the kernel of UNIX (BSD version 4.1), and the TCP/IP protocol became the standard communication module of the UNIX operating system after BSD version 4.2. 1982. Internet by ARPAnet, MILNET and several other computer networks merged into, as the Internet's early backbone network, ARPAnet experiments and laid the foundation for the existence and development of the Internet, a better solution to a series of theoretical and technical problems of the interconnection of heterogeneous machine networks.
In 1983, ARPAnet split into two parts: ARPAnet and purely military MILNET. in January of that year, ARPA took the TCP/IP protocol as the standard protocol of ARPAnet, and after that, people called this interconnection network with ARPAnet as the backbone network Internet, TCP/IP protocol clusters were researched, tested, and developed in the Internet. The TCP/IP protocol cluster was then studied, tested, and improved to become an easy-to-use and efficient protocol cluster in the Internet.
At the same time, local area networks (LANs) and other wide area networks (WANs) have played an important role in the further development of the Internet. Among them, the most notable is the U.S. National Science Foundation NSF (National Science Foundation) to establish the U.S. National Science Foundation network NSFnet, 1986, NSF established six supercomputer centers, in order to enable scientists and engineers across the country to **** enjoy these supercomputer facilities, the NSF has established its own In order to enable scientists and engineers across the country to enjoy these supercomputer facilities, NSF established its own computer network, NSFnet, based on a cluster of TCP/IP protocols.NSF established computer wide area networks (WANs) across the country, divided by region, and connected these regional networks to supercomputing centers, and finally interconnected the supercomputing centers. The regional network is generally composed of a number of geographically confined to a certain area, in the management of the computer belonging to a certain organization or in the economic interests of the same users interconnected into a high-speed data lines connecting computers in the main communication nodes of the regional network constitutes the backbone of the NSFnet, so that, when a user's computer and a certain region after the connection, it can use the facilities of any supercomputing center, can be connected to the network with the facilities of the supercomputing center, and can be connected to the network with the supercomputing center. When a user's computer is connected to an area, it can use the facilities of any supercomputing center, communicate with any user on the network, and also obtain a large amount of information and data provided by the network. This success led to NSFnet replacing ARPAnet in June 1990 as the backbone of the Internet.
NSFnet's greatest contribution to the Internet was to open it up to society as a whole, rather than just lending it to computer researchers, government employees, and government contractors as it had been in the past. However, with the rapid growth of online communications, NSF had to adopt newer network technologies to keep pace with development.In September 1990, a non-profit organization was established by Merit, IBM, and MCI - Advanced Networking and Science Corporation ANS (Advanced Network&Science,Inc).The purpose of ANS was to build a nationwide T3 class backbone network that could transmit data at a rate of 45Mb/s, which was equivalent to 1,400 pages of text information per second. By the end of 1991, the entire backbone of NSFnet was connected to the Class T3 backbone provided by ANS.
When ARPAnet was first built in December 1969 there were only four nodes, and by March 1972 there were only 23 nodes, until March 1977 there were only 111 nodes in total***. But in the past ten years, with the development of social science and technology, culture and economy, especially the great development of computer network technology and communication technology, with the human society from the industrial society to the information society transition trend is more and more obvious, people's awareness of information, the development and use of information resources more and more attention to strengthen, all these are strongly stimulate the development of the ARPAnet and the later developed into NSFnet, make the hosts connected to these two networks. So that the number of hosts and users connected to these two networks increased dramatically, in 1988, the number of computers connected by the NSFnet surged to 56,000, and since then every year more than 2 to 3 times the alarming rate of forward development, in 1994, the number of hosts on the Internet reached 3.2 million, connected to the world's 35,000 computer networks. Now, the Internet has more than 5,000,000 users, the number of monthly growth is still 10-15% forward, experts predict that by 1998, Internet users will exceed 100 million, to 2000, the world will have more than 1 million networks, 100 million hosts and more than 1 billion users. Today's Internet is no longer a field for computer personnel and military departments to conduct scientific research, but has become a development and use of information resources covering the global information ocean. On the Internet, according to the classification of the business engaged in, including advertising agencies, airlines, agricultural production companies, art, navigation equipment, bookstores, chemicals, communications, computers, consulting, entertainment, finance and trade, all kinds of stores, hotels and so on more than 100 categories, covering all aspects of social life, constituting a microcosm of the information society.
In 1995, the Internet began to be used on a large scale in the commercial field. In that year, the total revenue of the Internet business in the United States was 1 billion dollars, and it is expected that in 1996 it will reach 1.8 billion dollars. Providers of online services from the original like America Online and ProdigyService computer companies such as the development of such as AT& T, MCI, Pacific Bell and other communications operating companies to participate.
The market for Internet applications, from modems to Web servers and browsers, is booming because of the huge demand for business applications.
While the Internet is booming, its own product structure is changing as users' needs shift. 1994, all Internet software was almost exclusively TCP/IP protocols, and people needed a network architecture that was compatible with TCP/IP protocols; today, the center of gravity of the Internet has shifted to specific applications, such as the use of the WWW for business applications, and the use of the WWW for business applications, as well as the use of the WWW for business applications. The Web is the fastest-growing application on the Internet, with users surging from less than 4 million in 1994 to 10 million in 1995, and the number of Web sites reaching 30,000 in 1995.
Internet software is almost exclusively TCP/IP, when people needed a TCP/IP-compatible network architecture.
● Scale of the Internet
The Internet has become the largest international computer network in existence. Today, the Internet has been connected to more than 60,000 networks, officially connected to 86 countries, electronic mail can reach more than 150 countries, there are more than 4.8 million hosts through which it is connected together, there are more than 25 million users, the daily flow of information reaches more than a trillion bits (terrabyte), the monthly electronic mail exceeded 1 billion.
At the same time, the Internet application industry penetrated into various fields, from academic research to stock trading, from school education to entertainment games, from on-line information retrieval to on-line home shopping, etc., have made great progress. According to statistics, at present, in the Internet domain name distribution, .com -- that is, the largest proportion of business, 41%; .edu -- (science and education) has been relegated to the second line, 30% of the share. The business sector accounted for 75% of the Internet's growth last year.
● The Future of the Internet
From the current situation, the Internet market still has great potential for development, and its future applications will cover a wide range of areas from office **** enjoy information to marketing and services. In addition, the Internet brings e-trade is changing the traditional mode of today's business activities, and the convenience and extensive interconnection it provides will certainly have an impact on all aspects of social life in the future.
However, Internet also has its inherent shortcomings, into the network without overall planning and design, network topology is not clear as well as fault-tolerance and lack of reliability, and these are for many applications in the business field is critical. Security issues are another major factor plaguing the development of Internet users. Although there are now a number of programs and protocols to ensure that the Internet online business transactions are carried out reliably, but the real applicable and will dominate the market technology and products are not yet clear. In addition, the Internet is a centerless network. All of these issues have hindered the development of the Internet to a certain extent, only to solve these problems, the Internet can be better development.