Difference between line switching and message switching

Circuit switching and message switching are the different techniques used to connect multiple devices together in a dedicated manner. The main difference between circuit switching and message switching is that circuit switching establishes a dedicated physical connection between the two devices involved in the communication. On the other hand, message switching technology uses a store and forward mechanism to allow interaction between the sender and receiver.

When we want to connect multiple devices together, it is difficult to establish one-to-one communication. One solution is to install a point-to-point connection between each pair of devices. In practice, however, this is not possible. Therefore, switching a network is used when series of nodes are connected to each other through switches and network devices.

Comparison table

basis for comparison switching circuit storage exchange
basic A physical path is established between the two systems to make a phone call. Data is transmitted by storing and forwarding it to and from the switching device.
package storage Not saved sent directly Data is first stored and then forwarded.
transmission medium Analogue and digital across multiple media Digital across multiple media
addressing geographically hierarchical
routing manual guy The route is selected during connection establishment
special physical path not required Required for transfer
costs Larger than the message switch. Reduced by save and forward.

Definition of circuit switching

the circuit exchange is a switching technique in which a direct communication link is established between two nodes. The communication path is established by connecting a series of links between network nodes. Physically, the link contains a virtual logical channel for the connection. The circuit switching technique is mainly implemented in telephony, where the switch, after making the call, looks for the physical path from the caller’s address to the recipient’s telephone.

For the process to run, the three functions are performed.

  1. line structure : An end-to-end connection is established between nodes before data is transmitted.
  2. data transmission : Data is normally transmitted from transmitter to receiver in full-duplex mode.
  3. line break : When the data transfer is complete, the connection is closed and the occupied resources are freed.

Definition of message exchange

the message switch it works in a different way where messages are first stored and then forwarded to the dedicated recipient. Unlike circuit switching, it does not require a dedicated path for communication. It was the main disadvantage of circuit switching, which required the caller and the called to be connected by a dedicated path. However, circuit switching is very suitable for telephone systems as it serves the purpose.

Earlier, the telegraph system was used to allow electrical communication instead of a telephone. The telegraph system was cheaper than the telephone system because text messages transmitted in that environment are not real-time and fun. This leads to the store and mail forwarding system we use in messages.

In the messaging scheme, the message sent by the source is collected by an operator. The operator transmits the message to the intermediate nodes without knowing whether the path for the message is free or not. The message is transmitted from node to node and stored in a node when the link of the forwarding node is not available. As soon as the link is available, the message is sent to the next node.

Each message contains the full source and destination address. The message switching technique also creates a delay as the message is stored at a node until it reaches the forwarding node’s connection. Although this delay is tolerable as long as the environment is not real-time and the transmission medium can be used effectively.

Main differences between circuit switching and message switching

  1. Line switching reserves all the way for the end user to connect. In contrast, message switching technology does not establish real-time communication and sends data from a sender address to the destination address using network nodes.
  2. Similar to the telephone system, with circuit switching, data is sent directly to the recipient. In contrast, message switching first stores the data, then forwards it to the nearest available node, and the process repeats.
  3. The transmission medium used in circuit switching is analog whereas in message switching it can be both analog and digital.
  4. Addressing in circuit switching is fundamentally geographic. In contrast, message switching uses hierarchical switching.
  5. Circuit switching uses manual routing, while message switching does not have a previously defined route and is done at the time of connection configuration.
  6. Dedicated path for communication is necessarily required in circuit switching. On the other hand, no dedicated path is required for message switching.
  7. The cost of line switching is higher than message switching.


Switching is a technique that facilitates communication between two users. However, in circuit switching, an entire channel is dedicated to communication. On the other hand, for message switching, the sender and receiver need not be connected via a link, but use a store-and-forward technique to send the message node-by-node to the destination.

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