1-2Assume that Hosts B, D and E need this information. The source server establishes transmissionchannels for the devices of these users respectively. As the transmitted traffic over the network is indirect proportion to the number of users that receive this information, when a large number of usersneed the same information, the server must send many packets of information with the same content tothe users. While suitable for networks with small numbers of users, or where information transmitted tousers is significantly different, in other cases this is an inefficient use of the network, and when there islimited bandwidth, bottlenecks can develop in information transmission. In general, unicast is not goodfor the transmission of a great deal of the same information to multiple recipients.Information Transmission in the Broadcast ModeWhen you broadcast traffic, the system transmits information to all users on a network. Any user on thenetwork can receive the information, no matter if the information is needed or not. Figure 1-2 showsinformation transmission in broadcast mode.Figure 1-2 Information transmission in the broadcast modeAssume that Hosts B, D, and E need the information. The source server broadcasts this informationthrough the routers, reaching the targets, but also Hosts A and C on the network receive thisinformation.This is an efficient way to send the same content to densely distributed users. However, as we can seefrom the information transmission process, security and restricted use of paid services cannot beguaranteed. In addition, when only a small number of users on the same network need the information,the utilization ratio of the network resources is very low and the bandwidth resources are greatlywasted.Therefore, broadcast is disadvantageous in transmitting data to specific users, and is more bandwidthintensive.
