Notes

Outline

Chapter 6 Network Address Translation (NAT)

Network Address Translation Modification of source or destination IP address Needed by networks using RFC 1918 address scheme to route traffic to Internet Provides security by hiding a computer’s real IP address

Port Address Translation (PAT) a.k.a Overload NAT reduces public IP address consumption Many private IP addresses are translated to one public IP address

Port Address Translation

Security Benefits of NAT and PAT Router cannot forward packets from Internet to an internal network unless a NAT/PAT entry has been created in the router’s NAT table. In general, any connections not initiated from the inside are not allowed through the PAT device