Communicating with Other Computers


Computer networks are telecommunications networks that are used by computers to exchange data among them. There are roughly five kinds of computer networks as follows and the table shows some characteristics of the networks:

Network Range Exemplary Standards
Local Area Network (LAN) A building Ethernet
Metropolitan Area Network (MAN) A city and surrounding area ATM
Wide Area Network (WAN) A state or country The Internet
Wireless Network Depending on the availability of adjacent radio towers Wi-Fi and Bluetooth
Mobile/Cellular Network Depending on the availability of adjacent radio towers GSM, CDMA, and WiMAX

Local Area Network (LAN): Ethernet
It is designed to carry data within a geographically confined area, typically within a single building. For example, Ethernet can be up to a kilometer long and transfer at up to 10 gigabits per second. A hub is common connection point for devices in a network and a router is a device that forwards data packets along networks.

Metropolitan Area Network (MAN): ATM
It is designed to carry data over an area larger than LAN, but smaller than WAN, such as an entire city and its surrounding area. It can be used to connect computers and other networks like LANs.