ATM DSL - Firewall - Lan How to configure?

[NetOpsCenter]

Aloha,

Anybody on this list know of a how to for configuring a firewall for a 5 
IP ATM DSL? I know that the firewall has to come between the DSL modem 
and the Switch/router for the 5 IP's assigned. However the gateway IP 
must be able to be seen through the firewall in order for the ATM 
circuit to work. So you cant use addresses for the nics.  Is there a way 
to use  incoming and outgoing nic cards in a firewall FreeBSD  box for 
this purpose.
I am looking at a netgear firewall/switch for this purpose but I would 
rather use FreeBSD box for this firewall.

Thanks,

  
~Al Plant - Honolulu, Hawaii -  Phone:  808-284-2740
  + http://hawaiidakine.com + http://freebsdinfo.org + noc at hdk5.net +
  + http://internetohana.org   - Supporting - FreeBSD 6.* - 7.* +
"All that's really worth doing is what we do for others."- Lewis Carrol