Wide area network (WAN) is a telecommunication network that spreads over a large area of computer networking. A WAN network connects different small LAN and MAN networks.
A well-known example of a WAN network is the Internet. It covers cities, states, countries and even continents. It can be a public network or a private network.
There are two technologies which are used in the WAN network design. These technologies are explained below −
Circuit switched networks work on the principle of virtual connection that means all the messages will follow the same path and resources in this path are reserved for this connection. So, there is no requirement of keeping track of the fragmentation as the whole message is sent as a complete message.
Given below is the diagram of a circuit switched network −
Suppose, A wants to use the network; it has to ask for the request to obtain the one and then A can communicate with C. During the connection phase if B tries to communicate with D or any other user then it will get a busy signal from the network.
The examples of circuit switching are Traditional telephone network and Public Switched Telephone Network (PSTN).
In a packet switched network, depending on the outgoing link, the size of the packet is determined and these packets may follow a different route. These packets are collected and reassembled at the destination.
Given below is the diagram of a packet switched network −
Suppose A wants to send data to C and if B wants to send data to D, it is possible simultaneously. Here, the information is padded with a header which contains addresses of source and destination.
This header is sniffed by intermediate switching nodes to determine their route and destination.
Let us see the difference between two technologies in detail.
The orientation in circuit switching mainly depends on orientation of connection but the orientation in packet switching is connectionless type.
When it was getting designed the main purpose of circuit switching was for communication through voice while the main purpose of packet switching was for transmission of data.
There is no flexibility in the circuit switching. All the components follow the same path which was fixed in the beginning. They cannot create any path on their own. But, the packet switching is of flexible type because a path is getting created for travelling of each packet of data to reach its destination. Hence, it is a flexible type.
The messages which are sent by the sender are received in the same order as it was sent in the circuit switching. But, it is not received in the same order in the case of packet switching. Here the messages are received in a random manner and then assembled at the receiving station.
At the physical layer, the implementation of circuit switching is done while the packet switching is done at the network layer.
Most of the bilateral traffic is handled by packet switching while it doesn't depend on traffic but depends upon time and distance of the travelling of data or message in case of circuit switching.