Packet & Circuit Switching

Packet & Circuit Switching

1. Circuit Switching

   • The packets are sent in order one after the other. Each Packet follows the same route.
   • Data is split into fixed size packets of data.
   • The packets are reassembled but not re-ordered.
   • A route is reserved before transmission.

2. Packet Switching

   • Each packet is placed on the network individually.
   • Data is split into fixed size packets of data.
   • Packets follow most convenient route based on the network traffic.
   • Packets need to be re-ordered and re-assembled at the destination.

3. Packets

   • Header: Information required to transmit the packet to the correct Transmission Address, Destination Address & Packet Number.
   • Footer: Contains a couple of bits that tell the receiving device that it has reached the end of the packet. It carries out error checking.
   • Has a maximum amount of data that it can transmit. A Large file needs to be split into multiple packets. Each packet, only contains only part of the file.

4. Advantages of Packet over Circuit Switching

   • Very efficient use of a network, as each channel is only used for a short time.
   • Transmission is safer, it is impossible to intercept all packets as they use different routes.

5. Disadvantages of Packet over Circuit Switching

   • Must be reordered at the destination.
   • The transmission is only as fast as the slowest packet.