Take a look at RFC-1878.
At 01:08 PM 9/30/96 -0700, John McColley @ J F Engineering wrote:
>Let's see if I understand subnetting correctly.
>If I want to split a class C network to setup a firewall I would
>take the existing network, say a.b.c.0 with a netmask of
>255.255.255.0 and instead I would end up with 2 usable networks
>if I use a netmask of 255.255.255.192. I would end up with
>network a.b.c.64 with a netmask of 255.255.255.192 and network
>a.b.c.128 with a netmask of 255.255.255.192. Therefore, I would
>have available addresses of a.b.c.65 (netmask 255.255.255.192)
>through a.b.c.126, broadcast address would be a.b.c.127 and
>a.b.c.129 (netmask 255.255.255.192) through a.b.c.191, broadcast
>address would be a.b.c.192.
>I can't use a.b.c.0 through a.b.c.63 and a.b.c.193 through
>Does this sound right?
Paul Ferguson || ||
Consulting Engineering || ||
Reston, Virginia USA |||| ||||
tel: +1.703.716.9538 ..:||||||:..:||||||:..
e-mail: pferguso @
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