networking help

[Patrick Turnage]

Hello.
I have a setup here like this
I have directTV DSL, and the gateway has a dhcp server, I have the network
setup here like this:
I have a hub with my windows 2000 and windows xp and linux machine and dsl
gateway plugged in.
I manually assign my internet ip address because it is a static address:
eth0 6.12.14.13
then I use ip_aliasing on eth0:1 and give it the 192.168.0.1 address
and then I assign the other computers on my network an address from the
192.168.0.0 block, and I use iptables to filter and control the nat access
to the internet.
I want to some how block the dhcp broadcasts my dsl modem is sending out,
and to only make the linux machine send out the dhcp requests, but if for
some reason my linux machine is off then I want the windows machines to
grab the request from the dhcp server built in to the modem. See The
windows 2000 machine is my gf's and she doesn't know or understand how to
change her address to use a real ip in the case of the linux machine not
working ocorrectly when I'm not home.. 
Also what is the best way to get h323 or netmeeting/msn chat to work behind
nat?
Does anyone have some good iptables scripts that will allow for netmeeting
or msn chat, or aim chat, etc.. and speak freely?
Right now I'm doing internet conection sharing with my windows xp machine
and two nics in it, but I would take one nic out of the xp box and slap it
in the linux machine to make it have a nic, I do not want to put the
private network on its own physical network seperate from the dsl modem and
interface that has the direct dsl connection, because I do not want her to
have to move cables around, that could get into a bigger mess especially if
no one is here to talk her through it..

thanks



        -------------------------
Patrick Turnage
e-mail:pturnage at tampabay.rr.com
Telephone: (850) 459-7717
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