A WAN is a computer network that is developed over a wide area.
WAN is the acronym for Wide Area Network . The concept is used to name the computer network that extends over a large swath of territory, whether across a city, a country, or even worldwide. An example of a WAN network is the Internet itself.
WAN is distinguished from other types of networks, such as LAN ( Local Area Networks ) or PAN ( Personal Area Networks ), which have other configurations and scopes. LANs are very popular within companies or organizations, while PANs operate within the confines of a room or similar spaces.
Switching nodes in a WAN network
The WAN network, therefore, involves the interconnection of terminal equipment or other networks that are at great distances from each other. Its infrastructure requires various switching nodes and significant capacity to support the volume of data traffic.
A switching node is understood as the device that is responsible for handling traffic. These devices receive the data through an input line and must choose an output line to forward it.
Different topologies
WAN networks can have various topologies, such as the so-called point-to-point , which consists of the interconnection of nodes through dedicated channels that are always available for connection.
The ring topology, on the other hand, involves the connection of each node to two others, generating a particular pattern that increases the number of possible solutions to possible problems in connections using a cable.
Other topologies are star (one node becomes the connection center for the rest) and mesh (seeks the interconnection of all nodes, which means a greater capacity to overcome failures).
There are various types and typologies of WAN networks.
Types of WAN networks
* Circuit switched : a call is required to establish communication , after which each user has a direct link through the different segments of the network;
* Message switched : for this type of network, switches are usually computers that have the task of accepting traffic from the terminals to which they are connected. These devices examine the address found in the header of the messages and can save it to be attended to at another time. Messages may be deleted, stored, redirected or responded to automatically;
* Packet switched : the data sent by each user is divided, converted into a series of small parts that, once received by the recipient, are joined together to recompose the initial information. It is worth mentioning that each packet navigates the network independently, as if they were individual entities, which lightens traffic and facilitates error correction, since if only one of them fails, it is not necessary to resend the rest;
* Connection-oriented networks : they serve a large number of users, giving each one the feeling of having exclusive access to the resources. This concept is known as a virtual circuit (or virtual channel ), and belongs to the plane of channel and port multiplexing, that is, the union of a minimum of two information channels in a single transmission medium through a device called multiplexor;
* Non-connection-oriented networks : they are called datagrams and are characterized by going from the free state to the data transfer state directly. It should be noted that this type of network does not perform confirmation, error recovery, or flow control for the entire set of users; However, each node can access these functions individually. The Internet falls into this category.