What is Multicast?

There are 3 main methods of data transmission in IP networks: Unicast, Broadcast, Multicast.

• Multicast transmission type was developed to save bandwidth in IP networks. This type reduces traffic by allowing hosts to send a single packet to a selected group of hosts. To reach multiple destination hosts using unicast data transfer, the source host would need to send the same packet to each destination host. With multicast data transfer type, the source host can send just one packet, which can reach thousands of recipient hosts.

• Examples of multicast data transmission:

1) Video and audio mailing.
2) Exchange of information about routes used in routed protocols.
3) Software distribution.
4) News feeds.