For Class B, the first 16 bits (the first two numbers) represent the network part, while the remaining 16 bits represent the host part. For Class C, the first 24 bits represent the network part, while the remaining 8 bits represent the host part.

Class B addresses are ideal for medium to large-sized networks, while Class C addresses are suitable for smaller networks. Class B addresses have a subnet mask of 255.255.0.0, allowing for up to 65,534 hosts on a single network, while Class C addresses have a subnet mask of 255.255.255.0, limiting the number of hosts to 254.

Class B networks are also assigned to organizations with large networks. Class B networks have the following characteristics: Class B network addresses range from 128.0.0.0 to 191.255.255.255. The first 2 bits in a class B address are always 10 (128). In a class B network, the netid is determined by the first 8 bits (first 2 bytes).

Class C networks have the following characteristics: Class C network addresses range from 192.0.0.0 to 223.255.255.255. Class C networks use the first 24 bits to determine the netid. The three leftmost bits in a class C network are always 110 (192). The next 21 bits are used to define network.