What is the difference between multicasting and broadcasting?
Computer network transmissions can be unicast, multicast, and broadcast based. In unicast communication, there will be only one source and one destination node. Moreover, the relationship between the two nodes will be one-to-one. This is applicable in sending a message to a single destination node.
In multicast communication, there will be one source node and multiple or a group of destination nodes. Unlike unicast, a message in multicast network transmission will be sent all connected nodes but from a single source node. Moreover, the source node will transmit some message to a group of receivers simultaneously. Thus, the relation between the source and destination nodes will be one-to-many transmission.
This transmission method is highly applicable in disseminating server time information, stock prices, travel information, distance learning, audio and video streaming, video-on-demand (VoD) and so on purposes. Moreover, it is mainly supported by a protocol called Internet Group Management Protocol (IGMP), which is in addition to the IP protocol. The IGMP protocol is responsible for determining and managing the group membership information.
As opposed to multicast, in broadcast transmission method, a source node communicates with and broadcasts a message to all of the connected destination nodes. Furthermore, the relation between the source node and the destination nodes will be one-to-all communication.