IP addresses are typically classified into five classes based on the range of the first octet of the address. These classes are as follows:
Class A:
The first octet represents the network portion of the address, and the remaining three octets represent the host portion. The range of Class A addresses is 1.0.0.0 to 126.0.0.0, with the first bit of the first octet set to 0.
Class B:
The first two octets represent the network portion of the address, and the remaining two octets represent the host portion. The range of Class B addresses is 128.0.0.0 to 191.255.0.0, with the first two bits of the first octet set to 10.
Class C:
The first three octets represent the network portion of the address, and the last octet represents the host portion. The range of Class C addresses is 192.0.0.0 to 223.255.255.0, with the first three bits of the first octet set to 110.
Class D:
Class D addresses are used for multicasting. The range of Class D addresses is 224.0.0.0 to 239.255.255.255, with the first four bits of the first octet set to 1110.
Class E:
Class E addresses are reserved for experimental purposes. The range of Class E addresses is 240.0.0.0 to 255.255.255.255, with the first five bits of the first octet set to 11110.
