be assigned to any host on that network because it is
used to identify the network. This is how the network is
represented in the routing tables of routers throughout
the network. The other reserved IP address is the one
where all the host ID bits are 1; this address, called the
broadcast address, is used to send information to all the
hosts on the network and cannot be assigned to any
device. In the previous example with the Class C
network, the broadcast address for that network would
be 192.16.1.255. Class C networks can accommodate and
uniquely address 256 − 2 = 254 devices on each network.
The Internet has experienced explosive growth, and it
won’t be long before IANA runs out of available IPv4
address ranges to assign. A large number of the IPv4
address ranges that were initially allocated were also
used in private networks, so IANA decided to create a
group of private IPv4 address ranges for those networks.
Private IPv4 networks, defined by the Internet
Engineering Task Force (IETF) in RFC 1918: Address
Allocation for Private Internets, are meant to preserve
the IPv4 address space by having dedicated networks for
private networks. Three blocks of IP addresses (1 Class A,
16 Class B, and 256 Class C networks) are reserved for
private, internal use (see Table 16-5).
Table 16-5 Private IPv4 AddressesAddress ClassPrivate Network IDNetwork Address RangeA 10.0.0.0 10.0.0.0 to 10.255.255.255B 172.16.0.0 172.16.0.0 to 172.31.255.255C 192.168.0.0 192.168.0.0 to 192.168.255.255