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Re: mail administrator certification example

2004-07-30 11:12:10
On Fri, 2004-07-30 at 18:23, Mark wrote:
Paul Howarth wrote:

John Keown wrote:

I did not make the rule for the notation. That are part of the
binary number system. The total space is the 32 bit octal address
space. Therefore there are certain mathematical restrictions imposed
by both the binary and octal notation. The /xx defines that as some
power of 2 a /24 is 2 to 8 power. or 256. a / 25 is 2 the 7 and etc.

No, the /xx means use the leftmost xx bits (only). That's why it's
called the "prefix length". People may choose to implement it using
multiplication and/or division operators but there's no need at all
to do so.

Implementing this using real multiplication and/or division instructions
would be a rather odd way to go about things.

Indeed; I wasn't suggesting any sane programmer would do it this way ;-)

Cheers, Paul.
-- 
Paul Howarth <paul(_at_)city-fan(_dot_)org>