Answer:
In the transmission control protocol and internet protocol, subnet is define as when the devices contain similar prefix in the IP address. By using the subnet in the network it enhance the performance and the security system.
There are basically three types of class in the subnet as follow:
Class A: In this class, Only the first octet is use as the network identifier and other three octet are used for assigning the host in the network.
Class B: In this type of class, the first and second octet are assign as network portion and this can be use in between the 256 and 65532 host.
Class C: The IP address of class C are generally assign with the small size network as, it only contain 254 host in the network.