This tutorial shows how to set up network-address-translation (NAT) on a Linux system with iptables rules so that the system can act as a gateway and provide internet access to multiple hosts on a local network using a single public IP address. This is achieved by rewriting the source and/or destination addresses of IP packets as they pass through the NAT system.
Requirements:
CPU – PII or more
OS – Any Linux distribution
Software – Iptables
Network Interface Cards: 2
Here is my considerations:
Replace xx.xx.xx.xx with your WAN IP
Replace yy.yy.yy.yy with your LAN IP