network_address() and broadcast_address() yield the first and last
addresses of the network; num_addresses() gives the total number of
addresses in the network.
network_address() and broadcast_address() return an
ip_address vector
num_addresses() returns a numeric vector
Details
The broadcast address is a special address at which any host connected
to the network can receive messages. That is, packets sent to this address
are received by all hosts on the network.
In IPv4, the last address of a network is the broadcast address.
Although IPv6 does not follow this approach to broadcast addresses, the
broadcast_address() function still returns the last address of the network.