What I would do is ask my ISP to give me 1 address from his range
for the outside interface on my firewall and keep all of my
Class C for inside.
John McColley @ J F Engineering recently 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?
James P. Egan | jegan @
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