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

CHAPTER
3-1
Cisco 1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
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Configuring PPP over Ethernet with NAT
The Cisco 1811 and Cisco 1812 integrated services fixed-configuration routers support Point-to-Point
Protocol over Ethernet (PPPoE) clients and network address translation (NAT).
Multiple PCs can be connected to the LAN behind the router. Before the traffic from these PCs is sent
to the PPPoE session, it can be encrypted, filtered, and so forth.
Figure 3-1 shows a typical deployment
scenario with a PPPoE client and NAT configured on the Cisco router.
Figure 3-1 PPP over Ethernet with NAT
1 Multiple networked devices—desktops, laptop PCs, switches
2 Fast Ethernet LAN interface (inside interface for NAT)
3 PPPoE client—Cisco 1811 or Cisco 1812 integrated services router
4 Point at which NAT occurs
5 Fast Ethernet WAN interface (outside interface for NAT)
6 Cable modem or other server (for example, a Cisco 6400 server) that is connected to the Internet
7 PPPoE session between the client and a PPPoE server
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Internet