Prerequisites for Using Application Level Gateways with NAT.To find information about feature support and configuration, use the 'Feature Information for Using Application Level Gateways with NAT' section. This module was first published on May 2, 2005, and last updated on February 27, 2006.įinding Feature Information in This Module The support for IPSec ESP Through NAT feature provides the ability to support multiple concurrent IP Security (IPSec) Encapsulating Security Payload (ESP) tunnels or connections through a Cisco IOS NAT device configured in Overload or Port Address Translation (PAT) mode. Specific protocols that do imbed IP address information within the payload require support of an Application Level Gateway (ALG). These protocols include HTTP, Trivial File Transfer Protocol (TFTP), telnet, archie, finger, Network TimeProtocol (NTP), Network File System (NFS), remote login (rlogin), remote shell protocol (rsh), and remote copy protocol (rcp). Network Address Translation (NAT) performs translation service on any Transmission Control Protocol/User Datagram Protocol (TCP/UDP) traffic that does not carry source and/or destination IP addresses in the application data stream.

NAT Support of Skinny Client Control ProtocolĬonfiguration Examples for Using Application Level Gateways with NATĬonfiguring IPSec ESP Through NAT: ExampleĬonfiguring SPI Matching on the Endpoint Routers: Exampleĭeploying NAT Between an IP Phone and Cisco CallManager: Exampleįeature Information for Using Application Level Gateways with NAT How to Configure Application Level Gateways with NATĭisabling SPI Matching on the NAT Device or Changing the Default Portĭeploying NAT Between an IP Phone and Cisco CallManager Information About Configuring Application Level Gateways with NAT Prerequisites for Using Application Level Gateways with NAT Using Application Level Gateways with NAT Using Application Level Gateways with NAT Table Of Contents

Alg application layer gateway