Understanding Network Classes

Understanding Network Classes

1.     All addresses must have two parts, the network part and the node or host part.

2.     Addresses used in TCP/IP networks are four bytes long, called IP addresses, and are written in standard dot notation, which means a decimal number separated by dots.

3.     For example, 192.168.1.2. The decimal numbers must be within the numeric range of 0 to 255 to conform to the one-byte requirement.

4.     IP addresses are divided into classes with the most significant being classes A, B, and C depending on the value of the first byte of the address.

Class	First Byte
Class A	0-127
Class B	128-191
Class C	192-233

5.     The reason for the class division is to enable efficient use of the address numbers.

6.     If the division were the first two bytes to the network part and the last two bytes to the host part, then no network could have more than 2¹⁶ hosts.

7.     This would be impractical for large networks and wasteful for small networks.

8.     There are a few ways to assign IP addresses to the devices depending on the purpose of the network.

9.     If the network is internal, an intranet, not connected to an outside network, any class A, B, or C network number can be used.

Although this is possible but in the real world this approach would not allow for connecting to the Internet.