Information Transmission In The Broadcast Mode - 3Com 5500-EI PWR Install Manual

Assume that Hosts B, D and E need this information. The source server establishes transmission
channels for the devices of these users respectively. As the transmitted traffic over the network is in
direct proportion to the number of users that receive this information, when a large number of users
need the same information, the server must send many packets of information with the same content to
the users. While suitable for networks with small numbers of users, or where information transmitted to
users is significantly different, in other cases this is an inefficient use of the network, and when there is
limited bandwidth, bottlenecks can develop in information transmission. In general, unicast is not good
for the transmission of a great deal of the same information to multiple recipients.

Information Transmission in the Broadcast Mode

When you broadcast traffic, the system transmits information to all users on a network. Any user on the
network can receive the information, no matter if the information is needed or not. Figure 1-2 shows
information transmission in broadcast mode.
Figure 1-2 Information transmission in the broadcast mode
Assume that Hosts B, D, and E need the information. The source server broadcasts this information
through the routers, reaching the targets, but also Hosts A and C on the network receive this
information.
This is an efficient way to send the same content to densely distributed users. However, as we can see
from the information transmission process, security and restricted use of paid services cannot be
guaranteed. 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 greatly
wasted.
Therefore, broadcast is disadvantageous in transmitting data to specific users, and is more bandwidth
intensive.
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