System Administration Guide: IP Services

Class C Network Numbers

Class C network numbers use 24 bits for the network number and 8 bits for host numbers. Class C network numbers are appropriate for networks with few hosts—the maximum being 254. A class C network number occupies the first three bytes of an IPv4 address. Only the fourth byte is assigned at the discretion of the network owners. The following figure graphically represents the bytes in a class C address.

Figure 10–5 Byte Assignment in a Class C Address

Diagram shows bits 0-23 is network part and remaining
8 bits are host part of a 32 bit IPv4 Class C address.

The first byte of a class C network number covers the range 192–223. The second and third bytes each cover the range 1– 255. A typical class C address might be The first three bytes, 192.168.2, form the network number. The final byte in this example, 5, is the host number.