What is a Class C subnet?

Answer

A class C subnet uses the first three octets of an IP address to designate the network ID, and the remaining octet for the designation of the Host ID.

Host ID
|
|
ip address     xxx.xxx.xxx.xxx
|   |   |
|   |   |
Network ID

The first three bits of the first octet are always set to one one zero, 110 to indicate a Class C address therefore this leaves 21 bits to represent the Network ID. These 21 bits provide 2, 097,152 network addresses. The remaining 8 bits are used for the host ID and this provides 254 or (2⁸)-2 hosts per network

Keywords:IP Address subnet class