| BASIS OF COMPARISON | NAT | PAT |
| Description | NAT translates the private local IP to the global public IP address. | PAT translates the private IP addresses of an internal network to the public IP address with the help of port numbers. |
| Relationship | NAT has a one-to-one or many-to-one relationship. | PAT has a many-to-one relationship. |
| Types | There are two types of NAT: Static NAT and Dynamic NAT | There are two types of PAT: static and overloaded PAT. |
| IPv4 | NAT along with the IPv4 addressing scheme preserves IPv4 addresses and extends their lifespan. | PAT uses the IPv4 address along with the port number. |
| Relations | NAT is the superset of PAT. | PAT is a form of dynamic NAT. |
| Security | NAT improves security because the IP addresses of the internal hosts are invisible. | In PAT, the private address prevents the public address from being exposed. |
| Ports | NAT uses no ports in the translation process. | PAT uses source ports in the translation process. |