User's Manual

Wireless LAN Access Point User’s Guide
12
Creating a Subnet Mask
In addition to an IP address, you will need to define a subnet mask to ensure that
your computers only communicate with other computers and devices that are
within your network.
A subnet mask has four components that correspond to the four components of
the IP address. Like the IP address, each component can contain up to 256
numbers (0 to 255). These numbers determine if an IP address component must
be an exact match or if a range of numbers is acceptable.
If the subnet mask number for an IP component is 255, that component must be
an exact match for communication to take place. If the mask number is 0, any
number in the component is acceptable. A mask number between 0 and 255
determines a range of numbers between the number and 255 that are acceptable.
If you use a mask number of 250, IP address numbers between 250 and 255 are
acceptable.
For example: if you choose an IP address of 10.100.100.1 and a subnet mask of
255.255.255.0, the first three components of the IP address must match exactly,
and any number from 0 to 255 in the fourth component is acceptable for
communication to take place.
The use of these addresses and masks is limited only by your imagination. You
can use any rationale you like to select your addressing scheme.