What is a local area network (LAN), wide area network (WAN), and metropolitan area network (MAN)?

1, Local Area Network (LAN) is a computer network consisting of computers connected to each other in office buildings or campuses within a range of several hundred meters to a dozen kilometers. Computer LAN is widely used to connect personal computers or workstations in campuses, factories and organizations to facilitate the *** enjoyment of resources (e.g. printers) and data communication among personal computers or workstations.

2. MetropolitanAreaNetwork (MAN) uses technology that is basically similar to LANs, but on a larger scale. A MAN can cover several office buildings in close proximity to each other as well as a city; it can be a private network as well as a public network. A MAN can support both data and voice transmission, and can be connected to cable television. MANs generally contain only one or two cables and no switching equipment, making their design relatively simple.

3. A Wide Area Network (WAN) usually spans a large physical area, such as a country. A WAN contains a collection of machines that are used to run user applications, which we usually call hosts; these hosts are connected together by a communications subnet (communicationsubnet). The task of a communications subnet is to transmit messages between hosts. The design of a network can be greatly simplified by separating the communications-only portion of the subnet from the application portion of the hosts in a computer network.

Expanded:

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1. Local Area Network (LAN): A LAN is a communications network that interconnects various communication devices in a small area.

There are three main technologies that determine the characteristics of a LAN: the transmission medium used to transmit data; the topology used to connect the various devices; and the media access method used to *** enjoy the resources.

These three technologies determine, to a large extent, the type of data to be transmitted, the network's response time, throughput and utilization, and network applications and other network characteristics. The most important of these is the medium access control method, which plays a very important influence on the network characteristics

2, Metropolitan Area Network (MAN): Metropolitan Area Network (MAN) is a computer communications network established within a city, referred to as the MAN. There are many similarities between LAN and WAN.

The transmission medium of MAN is mainly fiber-optic cable, with a transmission rate of more than 100 megabits per second. All networked devices are connected to the media through a dedicated connection device, only the media access control in the realization of the method is different from the LAN.

3, Wide Area Network (Wide Area Network): a wide range of geographic scope of the computer communications network, referred to as the WAN, the scope of which can be beyond the city and the country to the global, and therefore the requirements for the communication and complexity are relatively high.

The WAN consists of a communication subnet and a resource subnet: the communication subnet is actually a data network, which can be a private network (switched or non-switched) or a public network (switched); the resource sub-system is a variety of computers, terminals, databases, and so on, which are connected to the network. This not only refers to hardware, but also includes software and data resources.

In practice, a LAN can be interconnected with a WAN, or through a WAN with a WAN located in another location, and then the LAN becomes an end system on the WAN.

References:

Baidu Encyclopedia - Local Area Network

Baidu Encyclopedia - Wide Area Network

Baidu Encyclopedia - Metropolitan Area Network