Computer Networks

Network can be classified into 3 major types depending upon the geographic spread. They are:

1. LAN (Local Area Network)

2. MAN (Metropolitan Area Network)

3. WAN (Wide Area Network)

LAN

A LAN or a Local Area Network is a network that is restricted to a small physical area. A small LAN might connect a few computers in an office or in a home; a large LAN could extend over an office park or university campus, connecting computers and other devices in a number of buildings. The major benefit of a local area network is that it can help to reduce cost by allowing people and microcomputers to share expensive resources.

There are three types of LANs. They are discussed below:

1. Dedicated Server LANs: Dedicated server LANs account for more than 70 percent of all installed LANs. A dedicated server LAN can connect with almost any other network, can handle very large databases and have a dedicated nework server.

2. Peer-to-Peer LANs: This network is a local area network that allows all users access to data on all workstations. In such networks, any computer on the network shares its resource such as hard disk and printer with any other computer on the same network.

3. Zero-slot LANs: This LAN operates like peer to peer LAN, but offers limited simple abilities such as sharing files and printers, transfer of files and transmission of e-mail. It is inexpensive. It does not require a network interface circuit card. Its adapter plug can be plugged into a serial or parallel port. This network usually can handle up to 30 computers

MAN

This is larger than a LAN and stands for Metropolitan Area Network. A MAN usually spans a geographical area that encompasses a city or country area. It interconnects various buildings or other facilities within this area. For example, linkages can be established between two commercial buildings. MAN technology has been rapidly developing in the area of cellular phone systems.

WAN

A wide area network (WAN) is one that operates over a vast distance (e.g., nationwide). Its nodes may span cities, states, or national boundaries. This network interconnects computers, LANs, MANs and other data transmission facilities. A WAN will employ communications circuits such as long distance telephone wires, microwaves, and satellites. Nationwide automated teller machines used in banking represent a common application of a wide area network.