is the most common subnet mask
used on computers connected to Internet Protocol (IP)
networks. An incorrectly configured subnet mask (also called netmask
) causes some types of network connection failures.
255.255.255.0 and Alternate Subnet Notation
The subnet mask 255.255.255.0 is also written as a 32-bit binary number:
11111111 11111111 11111111 00000000
The '0' digits of the mask span the IP range of the subnet, 8 bits or 255 addresses in this case.
In classless IP networks, the subnet representation is converted to a shorthand notation based on the number of '1' digits in the mask. In this case, /24.
Using 255.255.255.0 As An IP Address
Although it is the form of an IP address number, networks devices can only use 255.255.255.0 as a subnet mask and not as a working IP address. Attempting to use this number (or any IP number that starts with 255) as a device address will cause the IP network connection to fail due to the definition of number ranges on IP networks.