Introduction - If you have any usage issues, please Google them yourself
achieve basic NAT function is very simple. Subnets within a reservation to use the IP subnet, These external IP is not visible. Subnet only a small number of IP addresses corresponding to be the only truly global IP addresses. If these nodes need access to external networks, NAT on such a basic responsibility to the children of this node within the IP network into a single global IP then sent out. (Basic NAT will change the IP packet original IP address, but would not change the IP packet ports)