Variable Length Subnet Masks (VLSM), is a non-classful mask applied to a classful IP default mask. The defaults are:
Address Range Mask
Class A 126.96.36.199.0 - 188.8.131.52 255.0.0.0 (8 bit mask)
Class B 184.108.40.206 - 220.127.116.11 255.255.0.0 (16 bit mask)
Class C 192.0.0.0 - 18.104.22.168 255.255.255 (24 bit mask)
All masks of other values for each of the classes are of variable length.
Legacy KB System (APS) Data: RESL173801 V1.0, Originally authored by on , Last Edited by on
Related ranges: Modicon Quantum