ISP의 공인 IP주소의 절약 및 공공망과 연결되는 사설망을 침입자들로부터 보호하기 위해 사용.

셋팅

HQ_SE_Core_R2(config)#ip nat inside source list 1 interface Serial0/0/0 overload

HQ_SE_Core_R2(config-if)#ip nat inside

HQ_SE_Core_R2(config-if)#ip nat outside

결과

HQ_SE_Core_R2#show ip nat translations

Pro Inside global Inside local Outside local Outside global

icmp 200.1.2.2:3 192.168.5.33:3 200.1.2.1:3 200.1.2.1:3

icmp 200.1.2.2:4 192.168.5.33:4 200.1.2.1:4 200.1.2.1:4

icmp 200.1.2.2:5 192.168.5.33:5 200.1.2.1:5 200.1.2.1:5

icmp 200.1.2.2:6 192.168.5.33:6 200.1.2.1:6 200.1.2.1:6