Class C Addresses

Class C Addresses
The first three bytes of a Class C address are dedicated to the network portion of the address,
with only one measly byte remaining for the host address, by default. The format is
Network.Network.Network.Node
Using the example IP address 192.168.100.102, the network address is 192.168.100, and the
host address is 102.
In a Class C address, the first three bit positions are always the binary 110. The calculation
is as follows: 3 bytes, or 24 bits, minus 3 reserved positions, equals 21 positions left
for IANA manipulation. There are, therefore, 2 to the power of 21, or 2,097,152, possible
Class C networks.
Each unique Class C network uses one byte for node addresses. This leads to 2 to the power
of 8, or 256, minus the two reserved patterns of all 0s and all 1s in the host portion, for a total of
254 node addresses for each Class C network.
Extending IP Addresses
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Here’s an example of how to find a valid host ID in a Class C network:
192.168.100.0
All host bits turned off is the network ID.
192.168.100.1
The first host.
192.168.100.254
The last host.
192.168.100.255
All host bits turned on is the broadcast address.