Changes

Masquerading is better known in networking circles as Network Address Translation (NAT). When using a CentOS system as a gateway to the internet for a network of computers, masquerading allows all of the internal systems to use the IP address of the CentOS system when communicating over the internet. This has the advantage of hiding the internal IP addresses of any systems from malicious external entities and also avoids the necessity to allocate a public IP address to every computer on the network.

This service is also provided by most routers and gateways so this feature of the CentOS Firewall is rarely used.