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Re: mail administrator certification example

2004-07-30 08:55:25
John Keown wrote:

Then EVERY mailserver must be re-written as this does not conform to binary
math. You are working with a binary number system that has constraints. What
does xxx.yyy.zzz.3/24 mean.

Simple. It means xxx.yyy.zzz.3 with the last 8 (32-24) bits replaced with zeroes.

Does it mean xxx.yyy.zzz.0 to xxx.yyy.zzz.255 or does it mean xxx.yyy.zzz.3
to xxx.yyy.zzz+1.2. Next is how do you do the math in binary without
changing the principals of binary math.

You are asssuming the slash means "divide." A more reasonable reading is "masked with n ones and 32-n zeroes."