Static NAT with PAT

Use static NAT and PAT to translate private and public addresses and ports for transparent routing and address conservation. Define one-to-one mappings for source NAT and destination NAT to replace source or destination IP addresses between internal and external realms. For TCP and UDP, use static NAT and destination NAT to map both IP addresses and transport ports so multiple hosts can share a single external address. The system updates IP and transport checksums automatically during translation.