Circuit Switching vs Message Switching vs Packet Switching

Circuit Switching vs Message Switching vs Packet Switching

Switching    

  • Circuit Switching
  • Message Switching
  • Packet Switching
Circuit Switching
It creates a direct physical connection between two devices.Circuit Switching reserves bandwidth in advance.Unused bandwidth is wasted in Circuit Switching.Each Packet follows the same Path.
Example: Telephone System

Message Switching
Here no physical connection is established.The message to be sent is stored in the first switch and checks for errors and the retransmitted (store and forward).This requires enough disk space to store the message in each switch and is very costly.The solution is dividing the message into different packets.

Packet Switching
The message is divided into smaller packets and also no need to establish physical path in advance. It acquires bandwidth when needed and release soon after use. So no wastage of bandwidth. 
  • Datagram
  • Virtual Circuit                                                                                                                                                            
Datagram
Each Packet is treated independently and can go through any path.The datagram arrives at the destination at any order.
It is the responsibility of the transport layer to reorder the packet before sending to the destination port.Datagram is a connection less network service

Virtual Circuit
Here a route is established before packets are sent. All Packets follows the same virtual path. But it is not a dedicated path as in circuit switching. Virtual Circuit is a connection oriented network service.