Specifications

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Cisco 1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
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Chapter 4 Configuring PPP over ATM with NAT
Configuration Example
Note If you want to use NAT with a virtual-template interface, you must configure a loopback interface. See
Chapter 1, “Basic Router Configuration,” for information on configuring the loopback interface.
For complete information on NAT commands, see the Cisco IOS Release 12.3 documentation set. For
more general information on NAT concepts, see
Appendix B, “Concepts.”
Configuration Example
The following configuration example shows a portion of the configuration file for a client in the PPPoA
scenario described in this chapter.
The VLAN interface has an IP address of 192.168.1.1 with a subnet mask of 255.255.255.0. NAT is
configured for inside and outside.
Step 7
interface type number
Example:
Router(config)#interface fastethernet 0
Router(config-if)#
Enters configuration mode for the ATM WAN
interface (FE0 or FE1) to be the outside interface
for NAT.
Step 8
ip nat {inside | outside}
Example:
Router(config-if)# ip nat outside
Router(config-if)#
Identifies the specified WAN interface as the NAT
outside interface.
For details about this command and additional
parameters that can be set, as well as enabling
static translation, see the
Cisco IOS IP Command
Reference, Volume 1 of 4: Addressing and
Services.
Step 9
no shutdown
Example:
Router(config-if)# no shutdown
Router(config-if)#
Enables the configuration changes just made to the
Ethernet interface.
Step 10
exit
Example:
Router(config-if)# exit
Router(config)#
Exits configuration mode for the ATM interface.
Step 11
access-list access-list-number {deny | permit}
source [source-wildcard]
Example:
Router(config)# access-list 1 permit
192.168.1.0 0.0.0.255
Defines a standard access list permitting addresses
that need translation.
Note All other addresses are implicitly denied.
Command Purpose