text: pat/nat translations? when they are used there is a common misconception about pat and nat.  pat this is a many to one solution. in this situation you have multiple machines talking to one firewall and then the firewall talks to the destination machine with your information but with the firewall as the return address. the firewall then receives the information the passes it on to you with the received ip being the orginal distant end.  nat with nat you need to have multiple arin routable ips assigned to the public side of the firewall. this allows your private ips to pick up a public firewall ip and hold on to it when talking. this is what many companies do to protect their webservers. when they have multiple inside webservers with multiple inside ips they program the firewall to point one outside ip to a specific inside ip.  most home routers from linksys and dlink use pat but they just call it nat since this is how everyone knows it.