What Are the Three Major Classes of an IP Network?

The three major classes of an IP network are: A, B and C, which are used for normal addressing purposes. Two other classes exist in an IP network, classified as D and E, which are used for special purposes.

The three major classes differ greatly in their capabilities as well as the number of bits that are used for an ID associated with the IP network. Between the three classes, the number of bits used for network and host IDs ranges from eight to 24, though only class B has an equal number of network and host ID bits at 16 and 16.