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From: Sake Blok <sake@euronet.nl>
Message-Id: <199712142139.WAA06757@support.euronet.nl>
Subject: Re: Subnetting, Firewalls, Class C's
In-Reply-To: <3.0.5.32.19971214144719.009403c0@sundial.net> from "George M. Ellenburg" at "Dec 14, 97 02:47:19 pm"
To: gme@sundial.net (George M. Ellenburg)
Date: Sun, 14 Dec 1997 22:39:14 +0100 (CET)
Cc: isp@freebsd.org
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> Suffering from a cold, and heavy medication, I wish to run the
> following by some of you to confirm or deny that this subnetting
> example will work; everything tells me yes, but I would appreciate a
> second opinion:
> 
> ip ranges               netmask
> 204.181.150.1 -
> 204.181.150.14  255.255.255.240
> 
> 204.181.150.17 -
> 204.181.150.30  255.255.255.240
> 
> 204.181.150.33 -
> 204.181.150.46  255.255.255.240
> 
> 204.181.150.49 -
> 204.181.150.54  255.255.255.248
> 
> 204.181.150.57 -
> 204.181.150.254 255.255.255.56

A subnet must always be a power of 2 big or else the subnetmasking will 
not work. You have to split the last entry up into 3 sections:

204.181.150.57 -
204.181.150.62   255.255.255.248

204.181.150.65 -
204.181.150.126  255.255.255.192

and

204.181.150.129 -
204.181.150.254  255.255.255.128

At least, that is what you have to do if you don't want to change the
first 4 subnets.


Sake
-- 
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