- Generally spread over a larger geographical area from across a city to across a continent (100Km – 1000Km)
- Typically made up of a number of intercontinental switching nodes.
- Transmission from one device goes through internal nodes of the network to a specified destination device.
- Nodes are not concerned with the contents of the message but just bounce the message to the next node towards the destination.
- Implemented using circuits switching, packets switching frame relay or ATM networks.
A wide area network (WAN) is a computer network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries ). This is in contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively.
WANs are used to connect LANs and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers, provide connections from an organization’s LAN to the Internet. WANs are often built using leased lines. At each end of the leased line, a router connects to the LAN on one side and a hub within the WAN on the other. Leased lines can be very expensive. Instead of using leased lines, WANs can also be built using less costly circuit switching or packet switching methods. Network protocols including TCP/IP deliver transport and addressing functions. Protocols including Packet over SONET/SDH, MPLS, ATM and Frame relay are often used by service providers to deliver the links that are used in WANs. X.25 was an important early WAN protocol, and is often considered to be the “grandfather” of Frame Relay as many of the underlying protocols and functions of X.25 are still in use today (with upgrades) by Frame Relay.
Transmission rate usually range from 1200 bps to 6 Mbps, although some connections such as ATM and Leased lines can reach speeds greater than 156 Mbps. Typical communication links used in WANs are telephone lines, microwave links & satellite channels.
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