Appendix B IP Addresses and Subnetting
GS1510 Series User’s Guide
169
In this example, the company network address is 192.168.1.0. The first three 
octets of the address (192.168.1) are the network number, and the remaining 
octet is the host ID, allowing a maximum of 2
8
 – 2 or 254 possible hosts.
The following figure shows the company network before subnetting.  
Figure 85   Subnetting Example: Before Subnetting
You can “borrow” one of the host ID bits to divide the network 192.168.1.0 into 
two separate sub-networks. The subnet mask is now 25 bits (255.255.255.128 or 
/25).
The “borrowed” host ID bit can have a value of either 0 or 1, allowing two 
subnets; 192.168.1.0 /25 and 192.168.1.128 /25.