Specifications
Table Of Contents
- Contents
- Preface
- Getting Started
- Basic Router Configuration
- Interface Port Labels
- Viewing the Default Configuration
- Information Needed for Configuration
- Configuring Basic Parameters
- Configuring Static Routes
- Configuring Dynamic Routes
- Configuring Enhanced IGRP
- Basic Router Configuration
- Configuring Your Router for Ethernet and DSL Access
- Sample Network Deployments
- Configuring PPP over Ethernet with NAT
- Configuring PPP over ATM with NAT
- Configuring a LAN with DHCP and VLANs
- Configuring a VPN Using Easy VPN and an IPSec Tunnel
- Configure the IKE Policy
- Configure Group Policy Information
- Apply Mode Configuration to the Crypto Map
- Enable Policy Lookup
- Configure IPSec Transforms and Protocols
- Configure the IPSec Crypto Method and Parameters
- Apply the Crypto Map to the Physical Interface
- Create an Easy VPN Remote Configuration
- Verifying Your Easy VPN Configuration
- Configuration Example
- Configuring VPNs Using an IPSec Tunnel and Generic Routing Encapsulation
- Configuring a Simple Firewall
- Configuring a Wireless LAN Connection
- Sample Configuration
- Configuring Additional Features and Troubleshooting
- Additional Configuration Options
- Configuring Security Features
- Configuring Dial Backup and Remote Management
- Troubleshooting
- Reference Information
- Cisco IOS Software Basic Skills
- Concepts
- ROM Monitor
- Common Port Assignments
4-2
Cisco 1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
OL-6426-02
Chapter 4 Configuring PPP over ATM with NAT
In this scenario, the small business or remote user on the Fast Ethernet LAN can connect to an Internet
Service Provider (ISP) using the following protocols on the WAN connection:
• Asymmetric digital subscriber line (ADSL) over plain old telephone service (POTS) using the
Cisco
1801 router
• ADSL over integrated services digital network (ISDN) using the Cisco 1802 router
• Single-pair high-speed digital subscriber line (G.SHDSL) using the Cisco 1803 router
The Fast Ethernet interface carries the data packet through the LAN and off-loads it to the PPP
connection on the ATM interface. The ATM traffic is encapsulated and sent over the ADSL, ISDN, or
G.SHDSL lines. The dialer interface is used to connect to the ISP.
PPPoA
The PPPoA Client feature on the router provides PPPoA client support on ATM interfaces. A dialer
interface must be used for cloning virtual access. Multiple PPPoA client sessions can be configured on
an ATM interface, but each session must use a separate dialer interface and a separate dialer pool.
A PPPoA session is initiated on the client side by the Cisco 1800 series router.
NAT
NAT (represented as the dashed line at the edge of the Cisco router) signifies two addressing domains
and the inside source address. The source list defines how the packet travels through the network.
Configuration Tasks
Perform the following tasks to configure this network scenario:
• Configure the Dialer Interface
• Configure the ATM WAN Interface
• Configure DSL Signaling Protocol
• Configure Network Address Translation
An example showing the results of these configuration tasks is shown in the section “Configuration
Example.”