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.

Different classification, is a description of the different characteristics.

(a) according to the network coverage classification

According to the geographical position classification, can be divided into computer network LAN and wan and intracity networks.

LAN generally in dozens of meters to thousands of meters, within the scope of a local area network can hold just a few or even thousands of computer.

LAN distributed in smaller geographic range. Because they use different transmission can force the transmission medium, so the transmission distance LAN is different also.

LAN are often used to a group of people, such as a company, a unit, a building, a school, etc.

Wan coverage range is very wide, across borders, can the state border, and even the world. Wan is the public portion of the network, China telecom department general wan. We adopt the ISDN, ADSL access the Internet, is actually access the wan.

Through the local area network technology, wan can realize local network of IBM X61t battery interconnected. Man city is limited in size a city within the scope of regional network. Metro nets speed faster than the wan, accord with broadband trend, so now is developing very quickly. And the bureau domain, compared with distributed (net geographical range, generally speaking, the characteristics of the metro nets coverage between 10 to 100 km between. But should in fact it is a man said in developing and changing the concept, especially the standardization of different groups to the definition of weave, man is not identical. But with the rise of the market and the deepening of the research is close to the understanding of the man, the industry also gradually have reached some consensus. Tell from the concept, intracity networks is a common set of network, in a city to provide access and services. Area In particular, intracity networks is a single, independent, and clear “city area network”, by a network operators, usually is a service provider or the telecommunication operation business have and operation.

(2) according to the network topology structure classification

The topology of the network is to point to in the network communication lines and site (for a machine or equipment is) mutual connection form of geometry. According to the different topology structure, can be divided into star will network to network, the annular network, main line network of three basic types. In the three types of network structure, can be based on a combination of nets, tree star nets, mesh network and other types of network topology.

Star network structure

In the network structure of various star computer use their cable connected to the network, so if a site out of the question, will not affect the operation of the network. Star type network structure is now the most commonly used network topology structure.

With loop network structure

The annular network structure of each site through a communications medium into a closed ring. Ring network is easy to install and monitor, but limited HP CQ40 battery capacity, after the completion of the network, it is difficult to add new site. Therefore, now has basically don’t use a LAN with loop network structure.

Lu main line network structure

In the main line network structure of all site sharing a data channels. Main line network installation is simple and convenient, need the shortest cable laying, low cost, a site generally will not affect the entire network fault, but medium fault can lead to paralysis of the network. Main line network safety monitoring is more difficult, low, increase the new site will not single star nets Jane. So, the main line network structure now basically has been eliminated.

(3) according to the classification of the transmission medium

According to the network transmission medium classification, computer network can be divided into cable network and wireless network two kinds. LAN usually USES a single transmission medium, and the man and the wan DuoZhong transmission medium.

Cable network

Cable network refers to using coaxial cable, twisted pair, optical fiber cable medium is the network connection machine project.

The twisted-pair cable network and is the most common way of networking. It cheap, convenient in Ann, but vulnerable to interference, transfer rate is low, the transmission distance than coaxial cable to short. Optical fiber network using optical fiber as transmission medium, the transmission distance long, transfer rate high, resistance to interfere with strong sex, now are developing rapidly.

Wireless network

Wireless network using microwave, infrared, such as radio electromagnetic Dell 1720 battery wave transmission medium, because as a wireless network networking mode flexibility, so it’s a very promising network mode. At present, many universities and companies have been using a wireless network.

(4) according to the service object classification

According to the network service object classification can be divided into enterprise network, nets, and campus network type etc.

Enterprise nets

Enterprise nets as the name suggests, is a enterprise service for the computer network. Enterprise nets can include LAN, may include part of the wan. And for a possession, and ideas by better in other place no branches, the formation of a local area network also can meet the need to.

Campus network

Campus network for college, high school, is the primary service network. As the round “officer officer is connected” project starting, there are more and more of the campus network, and now the whole nation has had five round many middle schools and primary schools have the campus network.