There are several different types of computer networks. Computer networks can be characterized by their size as well as their purpose. The size of a network can be expressed by the geographic area they occupy and number of computers that are part of the network. Networks can cover any thing from a handful of devices within a single room to millions of devices spread across the entire globe.

Today when we speak of networks, we are generally referring to two primary categories: Personal area network (PAN), Local area networks (LAN) and wide-area networks (WAN). The category into which a network falls is determined by its size.

The different types of Networks

  1. Personal Area Network
  2. Local Area Network
  3. Wide Area Network
  4. Metropolitan Area Network

1. Personal Area Network (PAN)

A personal area network (PAN) is the interconnection of information technology devices within the range of an individual person, typically within a range of 10 meters.

For example, a person traveling with a laptop, a personal digital assistant (PDA), and a portable printer could interconnect them without having to plug anything in, using some form of wireless technology.

Typically, this kind of personal area network could also be interconnected without wires to the Internet or other networks.

PANs can be used for communication among the personal devices themselves (intrapersonal communication), or for connecting to a higher level network and the Internet (an uplink). However, it is possible to have multiple individuals using this same network within a residence.

If this is the case we can refer to the network as Home Area network (HAN). In this type of setup, all the devices are connected together using both wired and/or wireless.

All networked devices can be connected to a single modem as a gateway to the Internet.

2. Local Area Network (LAN)

 A LAN normally covers an area less than 2 mi; a WAN can be worldwide. Networks of a size in between are normally referred to as metropolitan area networks and span tens of miles.

A local area network (LAN) is usually privately owned and links the devices in a single office, building, or campus. LANs are designed to allow resources to be shared between personal computers or workstations.

The resources to be shared can include hardware (e.g., a printer), software (e.g., an application program), or data. A common example of a LAN, found in many business environments, links a work group of task-related computers, for example, engineering workstations or accounting PCs.

3. Wide Area Network (WAN)

A wide area network (WAN) provides long-distance transmission of data, image, audio, and video information over large geographic areas that may comprise a country, a continent, or even the whole world.

A WAN can be as complex as the backbones that connect the Internet or as simple as a dial-up line that connects a home computer to the internet. We normally refer to the first one as a switched WAN and to the second as a point-to-point WAN.

The switched WAN connects the end systems, which usually comprise a router (inter networking connecting device) that connects to another LAN or WAN.

The point-to-point WAN is normally a line leased from a telephone or cable TV provider that connects a home computer or a small LAN to an internet service provider (ISP).

A good example of a switched WAN is X.25, the asynchronous transfer mode (ATM) network.

4. Metropolitan Area Network (MAN)

A metropolitan area network (MAN) is a network with a size between a LAN and a WAN. It normally covers the area inside a town or a city.

It is designed for customers who need a high-speed connectivity, normally to the Internet, and have endpoints spread over a city or part of city.

A good example of a MAN is the part of the telephone company network that can provide a high-speed DSL line to the customer.