Wide Area Network ( WAN)

                                                             WAN - Wide Area Network

As the term implies, a WAN spans a large physical distance. The Internet is the largest WAN, spanning the Earth.

A WAN is a geographically-dispersed collection of LANs. A network device called a router connects LANs to a WAN. In IP networking, the router maintains both a LAN address and a WAN address.

A WAN differs from a LAN in several important ways. Most WANs like the Internet are not owned by any one organization but rather exist under collective or distributed ownership and management. WANs tend to use technology like ATM, Frame Relay and X.25 for connectivity over the longer distances.

 A WAN spans a large geographic area, such as a state, province or country. WANs often connect multiple smaller networks, such as local area networks (LANs) or metro area networks (MANs).

The world's most popular WAN is the Internet. Some segments of the Internet, like VPN-based extranets, are also WANs in themselves. Finally, many WANs are corporate or research networks that utilize leased lines.

WANs generally utilize different and much more expensive networking equipment than do LANs. Key technologies often found in WANs include SONET, Frame Relay, and ATM.

 WAN stands for Wide Area Network. As its name suggests, it is a computer network that covers a far wider area than a LAN (Local Area Network). WANs cover cities, countries, continents and the whole world.

A WAN is formed by linking LANs together. For example, several major LANs in a city can connect together forming a WAN.

When networks connect to form a bigger network a bigger WAN, the resulting network is called an internetwork, which is generically abbreviated to ‘an internet’. Now when all WANs in the world connect forming a global internet, we call it The Internet, which everyone knows! That’s why the Internet is always written with a capital I. It is the biggest WAN we have.

 WAN is an acronym for wide area network. This can be the network used within corporate office buildings which incorporates smaller connected networks. The Internet is often referred to as a WAN as it is a connection of smaller networks. {br}A WAN can be as small as one office building or as large as a network connecting various offices within a State/Province.

Transmission rate usually range from 1200 bits/s to 6 Mbit/s, although some connections such as ATM and Leased lines can reach speeds greater than 156 Mbit/s. Typical communication links used in WANs are telephone lines, microwave links & satellite channels.

Recently with the proliferation of low cost of Internet connectivity many companies and organizations have turned to VPN to interconnect their networks, creating a WAN in that way. Companies such as Cisco, New Edge Networks and Check Point offer solutions to create VPN networks.

Wide Area Network (WAN) is a computer network that covers a broad area LIKE any network whose communications links cross metropolitan, regional, or national boundaries . 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 a city respectively. The largest and most well-known example of a WAN is the Internet.

We use Wide Area network (WAN) in those cases where LAN cannot be used.

When more than two computers are involved in the application, a switched communication facility is used to enable all the computers to communicate with one other at different times. When the computers are located in different sites, public carries facilities must be used. As a result the network we get is known as wide area network. You can simply define WAN as any form of network (public, private) that covers a wide geographical area is known as WAN. Type of WAN used depends on the nature of network. 

For example there are 100 computers in a network and all computers belong to the same site. We want to send data between sites. So one method is to lease transmission lines from the public carriers. We will also install a private switching system at each site. Advantage of wide area network is that we can use this network to connect computers distributed over a large area. As LAN is limited to an office or home and does not provide services for long distance. For exchanging data between sites, services provided by wide are network are sufficient and up to the mark.

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.

Academic research into wide area networks can be broken down into three areas: Mathematical models, network emulation and network simulation.

WAN (Wide Area Network) is a common term in networking. To better understand it, you should know about LAN (Local Area Network). 

LAN (Local Area Network) is network of a company where the computers can be connected up to limited area. Approximately this network can be configured well up to 100 meters distance. The computers are connected through devices like Switches.  These kinds of networks are limited to a building or campus. The users can share the network resource and securities can be implemented only within the network.

WAN (Wide Area Network) connects two or more LANs and other networks so that computers at one location can communicate to the computers at far away some other location. Some Wide Area networks are built by private companies and only works for them and other are built by some Internet Service Providers. WANs are usually built through leased lines and routers are used to connect the network at one place to the network at other place. For example, a company has a network in UK. The company wants to open its office in USA. In order to connect the two offices in UK and USA, we have to install routers at both ends for communication. 

We can have unprecedented benefits from WAN. By sitting at one city or country the user can share the resources of the network in other city or country. For example the user can print the document or send an instant message by just one click. The users can use online softwares for communication and can work at the same time on the server database. The benefits are unlimited and it's up to the organization to what extent they need it for them.