HP FlexFabric 5700 Series Configuration Manual page 7

a separate copy of the same information to each of these hosts. Sending many copies can place a
tremendous pressure on the information source and the network bandwidth.
Unicast is not suitable for batch transmission of information.
Broadcast
In broadcast transmission, the information source sends information to all hosts on the subnet, even if
some hosts do not need the information.
Figure 2 Broadcast transmission
In Figure 2, only Host B, Host D, and Host E need the information. If the information is broadcast to the
subnet, Host A and Host C also receive it. In addition to information security issues, broadcasting to hosts
that do not need the information also causes traffic flooding on the same subnet.
Broadcast is not as efficient as multicast for sending data to groups of hosts.
Multicast
Multicast provides point-to-multipoint data transmissions with the minimum network consumption. When
some hosts on the network need multicast information, the information sender, or multicast source, sends
only one copy of the information. Multicast distribution trees are built through multicast routing protocols,
and the packets are replicated only on nodes where the trees branch.
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