Packets of some protocols, such as FTP and ICMP, contain IP addresses and port numbers in the Data field. To translate the IP addresses and port numbers contained in data, enable the NAT ALG function.
Most application layer protocol packets carry user IP addresses and port numbers. NAT translates only network layer addresses and transport layer ports. Therefore, an ALG can be configured to translate IP addresses and port numbers carried in the Data field of application layer packets.
The system view is displayed.
The NAT instance view is displayed.
The NAT ALG function is enabled for one or more application layer protocols.
To configure NAT for the SIP control channel and data channel separately, run the nat alg sip separate-translation command.
The configuration is committed.