Each number is double the one to its right. If a bit is "1," you add the value. If it's "0," you skip it. 11000000 = 128 + 64 = 192 . 3. Classful vs. Classless Networking
A true guru doesn't use the same mask for every subnet. allows you to use a /30 for a point-to-point link (2 hosts) and a /24 for a large department (254 hosts) within the same network range. ip subnetting from zero to guru pdf
How many bits do you need to "borrow" from the host side? Each number is double the one to its right