Internet links to almost every part of the world, it contain various kinds of information and huge, how to find the information we possibly need information, like how we look for in the big a small boat, we can use satellite positioning system, or communication system can be, and it needs to be used in the Internet search engine. Search engine is to point to gather information from the Internet, automatic after a certain after Read More…

In the 1980 s, the world almost all developed countries are now in the national education and built the computer network, the scientific research and cover the world behind each other international academic computer network Internet. This global computer information networks in the life to speed up the information transmission speed, for the overwhelming majority of teachers, students and scientific research personnel to provide a new network computing environment, thus fundamentally changing and promote the communication between them believe interest rates, resource sharing, scientific computing and the scientific research cooperation, become education and scientific research work in these countries the most important basic facilities, to promote the education and scientific research in these countries that the rapid development of the industry. In recent years, many developed countries to keep its economy and further in the leading edge of one, and put forward the “information superhighway plan, and are being put into practice. It is in those circumstances, the Chinese government decided to education and scientific research of the construction of Chinese calculations-machine network.

“China education and research computer network” of the overall construction goal is to make use of the advanced practical computer technology and network communication technology, the majority of higher school, promote connected these school campus network and information resources construction, and communication of the kingdom of existing international sex academic computer network interconnection, making it China’s entry into the world of higher school science and technology to the entrance of the quick and convenient. At the same time Lenovo Y510 battery develop a the world and the future high level talented person, improve the quality of teaching and the scientific research level of the most important infrastructure. In the conditions are ripe for other departments, provides the service, and with the domestic other computer network connected, and gradually form the computer network covering the whole country.

“China education and research computer network CERnet” is a including the national backbone network, area nets and campus network of level 3 levels of structure, network. The construction of the recent let including, in eight regional network connection of national backbone and international networking; The national network center; 8 regional network center and several area network; Function of complete network management system, to ensure the effective and reliable operation; Provide rich network resources and convenient application resource access method. “China education and research computer network” network center built in tsinghua university, area network center in Beijing, respectively in Shanghai, nanjing, xian, guangzhou, wuhan, chengdu, shenyang, eight of the city a famous university.

China education and research computer network has national coverage, and international and national computer network interconnection, so the method of Internet TCP/IP? Network system structure. China education and research computer network will make full use of the country has some public communication transmission was set, renting post and telecommunications departments digital data networks of DDN fiber optic cable line to form its backbone, and based on the using condition gradually improve the transmission rate.

China education and research computer network backbone node location choice considered universities and college students in countries distribution, communication infrastructure construction of specific conditions and geographical location, and other factors. Beijing, Shanghai, shenyang, guangzhou, wuhan, chengdu, nanjing, west Ann eight cities, is the backbone of the Chinese DDN ShuNiuJu and public utilities in China packet switching network and long distance telephone network node and, and, and, and consequently the institutions of higher learning and scientific research institutes are relatively concentrated area center, has good communication basic conditions and strong scientific research ability and level. So will set in the HP V6000 battery city the backbone node, and with the city as the center, building area network for the future, will build a nationwide CERnet education and research nets is beneficial,.

China education and research computer network network center is located at tsinghua university, through the nets network center, with international academic computer nets Internet network. The main network center position can include: network operation center; The network information center; High performance computing center and education training center and so on. China education and research computer network regional network the main function of the center is responsible for this area of the construction of network on things advisable. Area in university is the site of the center, responsible for the networking of college networking, and provides the technical support and service, also is the network management and all kinds of network application and service branch.

“China education and research computer network” gradually for the user to provide rich network should use resources. Including: email services; Web directory services; File access and Shared services; The science and technology information query service; Electronic news services; Information found services; Remote high speed information service and computing services; The remote computer education; The remote computer association with work; Education and scientific research management information service and so on.

“China education and research computer network” construction points in two stages. The first stage to the end of 1995, the backbone and international networking built, network center, area nets network center, network management system and basic network resources construction and application system, even the 100 or so of higher school access; The second stage from 1996 to 2000, built into the area network, connected to the majority of higher school into the net, provide more rich nets collaterals application resources.

Completed “China education and research computer network CERnet a demonstration project” is a including the national backbone, area nets and campus network of level 3 levels of structure, the computer network project. Its main technical contents include:

Built in 64 kbpsDDN line 8 regional network connection the national center of CERnet backbone, and with 128 KBPS international communication lines and Internet direct connection. The communication line rate can according to the need to upgrade;

Built in Beijing tsinghua university of CERnet national network center; Built respectively in Beijing, Shanghai, nanjing, xian, guangzhou, wuhan, chengdu, shenyang city, eight of the 10 universities 8 regional network center and the two main node. These regional network center and main node in addition to support the Dell M6300 battery operation of CERnet backbone outside this area, but also provide the institutions of higher learning networking services. In the relevant provinces and cities in the higher court help and support of the has made the area network development planning, and began to carry out; Built the function is more perfect CERnet network management system and safety system. Mainly includes: configuration management, failure management, security management, performance management and billing management function;

Built a batch of network resources and the application system, and has begun to provide services in the network;

CERnet using Internet TCP/IP network system structure and agreement technical standards. The national network center and the area network center in the world currently has the most advanced technology and the most complete function of network and computer equipment;

In the course of the construction of the CERnet, at all levels of network center is also a user’s education and collaterals nets training work, for promotion in China and popularization of the computer information network foundation knowledge and application to make positive contribution;

By the end of 1995, the higher colleges CERnet networking has reached more than 100 range, has covered except is Chinese Taiwan area, Hong Kong, Macao and the Tibetan autonomous region outside of all provinces, municipalities and autonomous regions, become at present China Internet connected with the biggest academic computer nets.

For historical reasons, the network has DuoZhong method, which can be classified according to the topology structure, network and 1 scope, the transmission medium, the service object characteristics such as classification.

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According to cover range, the network can be divided into LAN, wan and man, this is the most common computer network classification method. Each network have different features.

(a local area network (LAN)

LAN is the most network application form, is also the subject of a Internet. A computer can construct LAN in just a few or hundreds of Taiwan Read More…

The second generation, resources and communication subnet separate subnets more interconnected network host; The third generation, packet switching network; The fourth generation to OSI, as a representative of the standardization of the network; The fifth generation, in the Internet, driven to TCP/IP based, with optical fiber Read More…

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